Link against system-cxx-std-lib for GHC 9.4+ (#197)

* Link against system-cxx-std-lib for GHC 9.4+

* Drop OS checks for linking with stdc++ when GHC < 9.4

.github/workflows/build.yaml

@@ -4,13 +4,19 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2.3.4
+    - uses: actions/checkout@v2.4.0
       with:
           persist-credentials: false
           submodules: true
 
-    - uses: cachix/install-nix-action@v12
+    - uses: cachix/install-nix-action@v20
       with:
         nix_path: nixpkgs=channel:nixos-unstable
 
-    - run: nix-build -A hsPkgs.dear-imgui.components.exes --option trusted-public-keys "hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ= iohk.cachix.org-1:DpRUyj7h7V830dp/i6Nti+NEO2/nhblbov/8MW7Rqoo= cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=" --option substituters "https://hydra.iohk.io https://iohk.cachix.org https://cache.nixos.org/"
+    - uses: cachix/cachix-action@v12
+      with:
+        name: hs-dear-imgui
+        authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+
+    - run: nix-build --version
+    - run: nix-build -A hsPkgs.dear-imgui.components.exes

.gitignore

@@ -21,3 +21,4 @@ cabal.project.local
 cabal.project.local~
 .HTF/
 .ghc.environment.*
+/imgui.ini

ChangeLog.md

@@ -0,0 +1,125 @@
+# Changelog for dear-imgui
+
+## [2.2.0]
+
+- `imgui` updated to [1.89.9].
+- Update bounds for ghc-9.6.
+- Exposed `DearImGui.Raw.Context`.
+- Added `getCursorPos``.
+- Fix TabItem flags type.
+
+## [2.1.3]
+
+- Fixed off-by-1 in internal Text wrapper.
+- Fixed sliderFloat* Raw calls
+- Added `formatPtr` to Raw.dragFloat* and Raw.sliderFloat*
+
+## [2.1.2]
+
+- Fixed glfw example build flags.
+- Added `plotLines`.
+- Added `setNextItemOpen`.
+
+## [2.1.1]
+
+- Build flag fix for MacOS.
+
+## [2.1.0]
+
+- `imgui` updated to [1.88].
+    * Breaking: `ImGuiKeyModFlags` renamed to `ImGuiModFlags`.
+
+## [2.0.0]
+
+- `String` arguments replaced with `Text`.
+  * Upgrading to `text-2` recommended to reap the UTF-8 benefits.
+
+## [1.5.0]
+
+- Added table wrappers.
+- Added popup wrappers.
+- Added `selectableWith`/`SelectableOptions` to expose optional arguments.
+- Fix GHC-9.2 compatibility.
+
+## [1.4.0]
+
+- `imgui` updated to [1.87].
+- Added `DearImGui.Vulkan.vulkanAddTexture`.
+- Added `DearImGui.GLFW.glfwCursorPosCallback`.
+  * Apps that don't install backend callbacks, *must* call it themselves.
+- Added flags `use-wchar32` (default on) and `disable-obsolete` (default off).
+
+## [1.3.1]
+
+- `imgui` updated to [1.86].
+
+## [1.3.0]
+
+- Added `DearImGui.FontAtlas` and related `DearImGui.Raw.Font.*` bits.
+- Removed old font atlas functions from `DearImGui` and `DearImGui.Raw`.
+
+## [1.2.2]
+
+- `imgui` updated to [1.85].
+
+## [1.2.1]
+
+- Added `DearImGui.Raw.DrawList` for drawing primitives.
+- Added `DearImGui.Raw.IO` with attribute setters.
+- Added `DearImGui.Raw.ListClipper` for efficient list viewports.
+
+## [1.2.0]
+
+- Fixed `nullPtr` in place of default arguments.
+- Added functions for getting window position and size.
+- Added `invisibleButton`.
+- Added `inputTextMultiline` and `inputTextWithHint`.
+- Changed `beginChild` and related `withChild*` to use full arguments.
+- Added `withChildContext` to run actions inside other child window.
+- Added `getCurrentContext`, `setCurrentContext`.
+- Added `image` and `imageButton`.
+- Added font atlas utilities.
+
+## [1.1.0]
+
+- `imgui` updated to [1.84.2].
+- Removed unused Window argument from SDL `newFrame` to match 1.84.
+- Added GLFW backend callbacks.
+- Added more withXXX wrappers.
+
+## [1.0.2]
+
+- Added `withID` and `ToID(..)` to make composable components possible.
+
+## [1.0.1]
+
+- Fixed missing headers in source dist.
+
+## [1.0.0]
+
+Initial Hackage release based on [1.83].
+
+[1.0.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.0.0
+[1.0.1]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.0.1
+[1.0.2]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.0.2
+[1.1.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.1.0
+[1.2.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.2.0
+[1.2.1]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.2.1
+[1.2.2]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.2.2
+[1.3.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.3.0
+[1.3.1]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.3.1
+[1.4.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.4.0
+[1.5.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v1.5.0
+[2.0.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.0.0
+[2.1.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.1.0
+[2.1.1]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.1.1
+[2.1.2]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.1.2
+[2.1.3]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.1.3
+[2.2.0]: https://github.com/haskell-game/dear-imgui.hs/tree/v2.2.0
+
+[1.89.9]: https://github.com/ocornut/imgui/releases/tag/v1.89.9
+[1.87]: https://github.com/ocornut/imgui/releases/tag/v1.87
+[1.86]: https://github.com/ocornut/imgui/releases/tag/v1.86
+[1.85]: https://github.com/ocornut/imgui/releases/tag/v1.85
+[1.84.2]: https://github.com/ocornut/imgui/releases/tag/v1.84.2
+[1.83]: https://github.com/ocornut/imgui/releases/tag/v1.83

Main.hs

@@ -5,9 +5,12 @@
 
 module Main (main) where
 
+import Control.Monad
 import Data.IORef
+import qualified Data.Vector as Vector
 import DearImGui
-import DearImGui.OpenGL
+import DearImGui.OpenGL3
+import DearImGui.Internal.Text (pack)
 import DearImGui.SDL
 import DearImGui.SDL.OpenGL
 import Control.Exception
@@ -22,23 +25,39 @@ main = do
     bracket (glCreateContext w) glDeleteContext \glContext ->
     bracket createContext destroyContext \_imguiContext ->
     bracket_ (sdl2InitForOpenGL w glContext) sdl2Shutdown $
-    bracket_ openGL2Init openGL2Shutdown do
+    bracket_ openGL3Init openGL3Shutdown do
       checkVersion
       styleColorsLight
 
       checked <- newIORef False
       color <- newIORef $ ImVec3 1 0 0
-      slider <- newIORef 0.42
-      loop w checked color slider
+      slider <- newIORef (0.42, 0, 0.314)
+      r <- newIORef 4
+      pos <- newIORef $ ImVec2 64 64
+      size' <- newIORef $ ImVec2 512 512
+      selected <- newIORef 4
+      tab1 <- newIORef True
+      tab2 <- newIORef True
+      loop w checked color slider r pos size' selected tab1 tab2
 
-      openGL2Shutdown
 
-loop :: Window -> IORef Bool -> IORef ImVec3 -> IORef Float -> IO ()
-loop w checked color slider = do
-  quit <- pollEvents
+loop
+  :: Window
+  -> IORef Bool
+  -> IORef ImVec3
+  -> IORef (Float, Float, Float)
+  -> IORef Int
+  -> IORef ImVec2
+  -> IORef ImVec2
+  -> IORef Int
+  -> IORef Bool
+  -> IORef Bool
+  -> IO ()
+loop window checked color slider r pos size' selected tab1Ref tab2Ref = do
+  shouldQuit <- checkEvents
 
-  openGL2NewFrame
-  sdl2NewFrame w
+  openGL3NewFrame
+  sdl2NewFrame
   newFrame
 
   -- showDemoWindow
@@ -46,9 +65,34 @@ loop w checked color slider = do
   -- showAboutWindow
   -- showUserGuide
 
+  setNextWindowPos pos ImGuiCond_Once Nothing
+  setNextWindowSize size' ImGuiCond_Once
+  -- Works, but will make the window contents illegible without doing something more involved.
+  -- setNextWindowContentSize size'
+  -- setNextWindowSizeConstraints size' size'
+  setNextWindowCollapsed False ImGuiCond_Once
+
+  setNextWindowBgAlpha 0.42
+
   begin "My Window"
+
   text "Hello!"
 
+  beginTabBar "My tab bar" ImGuiTabBarFlags_Reorderable >>= whenTrue do
+    beginTabItem "Tab 1" tab1Ref ImGuiTabItemFlags_None >>= whenTrue do
+      text "Tab 1 is currently selected."
+      endTabItem
+    beginTabItem "Tab 2" tab2Ref ImGuiTabItemFlags_None >>= whenTrue do
+      text "Tab 2 is selected now."
+      endTabItem
+    reOpen <- tabItemButton "ReopenTabs" ImGuiTabItemFlags_Trailing
+    when reOpen do
+      writeIORef tab1Ref True
+      writeIORef tab2Ref True
+    endTabBar
+
+  listBox "Items" r [ "A", "B", "C" ]
+
   button "Click me" >>= \case
     True  -> openPopup "Button Popup"
     False -> return ()
@@ -66,7 +110,7 @@ loop w checked color slider = do
     True  -> putStrLn "Oh hi Mark"
     False -> return ()
 
-  sameLine >> arrowButton "Arrow" ImGuiDirUp
+  sameLine >> arrowButton "Arrow" ImGuiDir_Up
 
   sameLine >> checkbox "Check!" checked >>= \case
     True  -> readIORef checked >>= print
@@ -74,19 +118,49 @@ loop w checked color slider = do
 
   separator
 
-  sliderFloat "Slider" slider 0.0 1.0
+  dragFloat3 "Slider" slider 0.1 0.0 1.0
 
   progressBar 0.314 (Just "Pi")
 
+  beginChild "Child" (ImVec2 0 0) True ImGuiWindowFlags_None
+
   beginCombo "Label" "Preview" >>= whenTrue do
     selectable "Testing 1"
     selectable "Testing 2"
     endCombo
 
+  combo "Simple" selected [ "1", "2", "3" ]
+
+  endChild
+
+  text "ListClipper"
+  withChildOpen "##fixed" (ImVec2 0 200) True ImGuiWindowFlags_None do
+    let lotsOfItems = Vector.generate 50 (pack . mappend "Item " . show)
+    withListClipper Nothing lotsOfItems text
+
+  text "ListClipper, Haskell-powered"
+  withChildOpen "##infinite" (ImVec2 0 200) True ImGuiWindowFlags_None do
+    let infiniteItems = map (pack . mappend "Item " . show) [0 :: Int ..]
+    withListClipper Nothing infiniteItems text
+
+  text "Ethereal ListClipper"
+  withChildOpen "##ethereal" (ImVec2 0 200) True ImGuiWindowFlags_None do
+    withListClipper Nothing (ClipRange (0 :: Int) 1000) $
+      text . pack . mappend "Item " . show
+
   plotHistogram "A histogram" [ 10, 10, 20, 30, 90 ]
 
   colorPicker3 "Test" color
 
+  treeNode "Tree Node 1" >>= whenTrue do
+    treeNode "Tree Node 2" >>= whenTrue do
+      treePop
+
+    treeNode "Tree Node 3" >>= whenTrue do
+      treePop
+
+    treePop
+
   beginMainMenuBar >>= whenTrue do
     beginMenu "Hello" >>= whenTrue do
       menuItem "Hello"
@@ -103,15 +177,17 @@ loop w checked color slider = do
   render
 
   glClear GL_COLOR_BUFFER_BIT
-  openGL2RenderDrawData =<< getDrawData
+  openGL3RenderDrawData =<< getDrawData
 
-  glSwapWindow w
+  glSwapWindow window
 
-  if quit then return () else loop w checked color slider
+  if shouldQuit
+    then return ()
+    else loop window checked color slider r pos size' selected tab1Ref tab2Ref
 
   where
 
-    pollEvents = do
+    checkEvents = do
       ev <- pollEventWithImGui
 
       case ev of
@@ -121,9 +197,9 @@ loop w checked color slider = do
                 QuitEvent -> True
                 _         -> False
 
-          (isQuit ||) <$> pollEvents
+          (isQuit ||) <$> checkEvents
 
 
 whenTrue :: IO () -> Bool -> IO ()
 whenTrue io True  = io
-whenTrue io False = return ()
+whenTrue _io False = return ()

README.md

@@ -25,90 +25,96 @@ OpenGL:
 
 ```
 package dear-imgui
-  flags: +sdl +opengl
+  flags: +sdl +opengl3
 ```
 
 With this done, the following module is the "Hello, World!" of ImGui:
 
 ``` haskell
-{-# language BlockArguments #-}
-{-# language LambdaCase #-}
 {-# language OverloadedStrings #-}
 
 module Main ( main ) where
 
-import Control.Exception
-import Control.Monad.IO.Class
-import Control.Monad.Managed
 import DearImGui
-import DearImGui.OpenGL
+import DearImGui.OpenGL3
 import DearImGui.SDL
 import DearImGui.SDL.OpenGL
+
 import Graphics.GL
 import SDL
 
+import Control.Monad.Managed
+import Control.Monad.IO.Class ()
+import Control.Monad (when, unless)
+import Control.Exception (bracket, bracket_)
+
 main :: IO ()
 main = do
   -- Initialize SDL
   initializeAll
 
-  runManaged do
-    -- Create a window using SDL. As we're using OpenGL, we need to enable OpenGL too.
-    w <- do
+  runManaged $ do
+    -- Create a window using SDL; as we're using OpenGL, we enable OpenGL too
+    window <- do
       let title = "Hello, Dear ImGui!"
       let config = defaultWindow { windowGraphicsContext = OpenGLContext defaultOpenGL }
       managed $ bracket (createWindow title config) destroyWindow
 
     -- Create an OpenGL context
-    glContext <- managed $ bracket (glCreateContext w) glDeleteContext
-
+    glContext <- managed $ bracket (glCreateContext window) glDeleteContext
     -- Create an ImGui context
     _ <- managed $ bracket createContext destroyContext
 
     -- Initialize ImGui's SDL2 backend
-    _ <- managed_ $ bracket_ (sdl2InitForOpenGL w glContext) sdl2Shutdown
-
+    managed_ $ bracket_ (sdl2InitForOpenGL window glContext) sdl2Shutdown
     -- Initialize ImGui's OpenGL backend
-    _ <- managed_ $ bracket_ openGL2Init openGL2Shutdown
-
-    liftIO $ mainLoop w
+    managed_ $ bracket_ openGL3Init openGL3Shutdown
 
+    liftIO $ mainLoop window
 
 mainLoop :: Window -> IO ()
-mainLoop w = do
-  -- Process the event loop
-  untilNothingM pollEventWithImGui
-
+mainLoop window = unlessQuit $ do
   -- Tell ImGui we're starting a new frame
-  openGL2NewFrame
-  sdl2NewFrame w
+  openGL3NewFrame
+  sdl2NewFrame
   newFrame
 
   -- Build the GUI
-  bracket_ (begin "Hello, ImGui!") end do
+  withWindowOpen "Hello, ImGui!" $ do
     -- Add a text widget
     text "Hello, ImGui!"
 
     -- Add a button widget, and call 'putStrLn' when it's clicked
-    button "Clickety Click" >>= \case
-      False -> return ()
-      True  -> putStrLn "Ow!"
+    button "Clickety Click" >>= \clicked ->
+      when clicked $ putStrLn "Ow!"
 
   -- Show the ImGui demo window
   showDemoWindow
 
   -- Render
   glClear GL_COLOR_BUFFER_BIT
-
   render
-  openGL2RenderDrawData =<< getDrawData
-
-  glSwapWindow w
-
-  mainLoop w
+  openGL3RenderDrawData =<< getDrawData
 
+  glSwapWindow window
+  mainLoop window
   where
-    untilNothingM m = m >>= maybe (return ()) (\_ -> untilNothingM m)
+  -- Process the event loop
+  unlessQuit action = do
+    shouldQuit <- gotQuitEvent
+    unless shouldQuit action
+
+  gotQuitEvent = do
+    ev <- pollEventWithImGui
+
+    case ev of
+      Nothing ->
+        return False
+      Just event ->
+        (isQuit event ||) <$> gotQuitEvent
+
+  isQuit event =
+    eventPayload event == QuitEvent
 ```
 
 # Hacking

cabal.project

@@ -1,3 +1,4 @@
 packages: *.cabal
 package dear-imgui
-  flags: +sdl2 +opengl +vulkan
+  flags: +sdl +glfw +opengl2 +opengl3 +vulkan +examples
+  ghc-options: -Wall -Wcompat -fno-warn-unused-do-bind

dear-imgui.cabal

@@ -1,15 +1,82 @@
 cabal-version: 3.0
-name: dear-imgui
-version: 1.0.0
-build-type: Simple
 
-flag opengl
+name: dear-imgui
+version: 2.2.0
+author: Oliver Charles
+maintainer: ollie@ocharles.org.uk, aenor.realm@gmail.com
+license: BSD-3-Clause
+
+category: Graphics
+synopsis: Haskell bindings for Dear ImGui.
+description:
+  The package supports multiple rendering backends.
+  Set package flags according to your needs.
+
+build-type: Simple
+extra-source-files:
+  README.md,
+  ChangeLog.md
+
+extra-source-files:
+  imgui/*.h,
+  imgui/backends/*.h,
+  imgui/backends/*.mm,
+  imgui/imconfig.h,
+  imgui/LICENSE.txt
+
+common exe-flags
+  if flag(debug)
+    if os(linux)
+      ghc-options: -Wall -g -rtsopts -dcore-lint -debug
+      cc-options: -g -O0 -fsanitize=address -fno-omit-frame-pointer
+      cxx-options: -g -O0 -fsanitize=address -fno-omit-frame-pointer -std=c++11
+    if os(darwin)
+      ghc-options: -Wall -g -rtsopts -dcore-lint -debug
+      cc-options: -g -O0 -fsanitize=address -fno-omit-frame-pointer
+      cxx-options: -g -O0 -fsanitize=address -fno-omit-frame-pointer -std=c++11
+    if os(windows)
+      ghc-options: -Wall -g -rtsopts -dcore-lint -debug
+      cc-options: -g -O0
+      cxx-options: -g -O0 -std=c++11
+  else
+    if os(linux)
+      ghc-options: -Wall -O2
+      cc-options: -O2
+      cxx-options: -std=c++11 -O2
+    if os(darwin)
+      ghc-options: -Wall -O2
+      cc-options: -O2
+    if os(windows)
+      ghc-options: -Wall -O2
+      cc-options: -O2
+
+source-repository head
+  type: git
+  location: https://github.com/haskell-game/dear-imgui.hs
+
+flag debug
   description:
-    Enable OpenGL backend.
+    Enable debug mode.
+  default:
+    False
+  manual:
+    True
+
+flag opengl2
+  description:
+    Enable OpenGL 2 backend.
+  default:
+    False
+  manual:
+    True
+
+flag opengl3
+  description:
+    Enable OpenGL 3 backend.
   default:
     True
   manual:
-    False
+    True
 
 flag vulkan
   description:
@@ -25,52 +92,140 @@ flag sdl
   default:
     True
   manual:
+    True
+
+flag sdl-renderer
+  description:
+    Enable SDL Renderer backend (requires the SDL_RenderGeometry function available in SDL 2.0.18+).
+    The sdl configuration flag must also be enabled when using this flag.
+  default:
     False
+  manual:
+    True
+
+flag glfw
+  description:
+    Enable GLFW backend.
+  default:
+    False
+  manual:
+    True
+
+flag examples
+  description:
+    Build executable examples.
+  default:
+    False
+  manual:
+    True
+
+flag disable-obsolete
+  description:
+    Don't define obsolete functions/enums/behaviors. Consider enabling from time to time after updating to avoid using soon-to-be obsolete function/names.
+  default:
+    False
+  manual:
+    True
+
+flag use-wchar32
+  description:
+    Use 32-bit for ImWchar (default is 16-bit) to support unicode planes 1-16. (e.g. point beyond 0xFFFF like emoticons, dingbats, symbols, shapes, ancient languages, etc...)
+  default:
+    True
+  manual:
+    True
+
+flag use-ImDrawIdx32
+  description:
+    Use 32-bit vertex indices (default is 16-bit) is one way to allow large meshes with more than 64K vertices.
+    Your renderer backend will need to support it (most example renderer backends support both 16/32-bit indices).
+    Another way to allow large meshes while keeping 16-bit indices is to handle ImDrawCmd::VtxOffset in your renderer.
+    Read about ImGuiBackendFlags_RendererHasVtxOffset for details.
+  default:
+    True
+  manual:
+    True
+
+common common
+  build-depends:
+      base
+        >= 4.12 && < 4.19
+  default-language:
+      Haskell2010
 
 library
-  exposed-modules:
-    DearImGui
-    DearImGui.Context
+  import: common
   hs-source-dirs:
     src
-  default-language:
-    Haskell2010
-  ghc-options:
-    -Wall
+  exposed-modules:
+    DearImGui
+    DearImGui.FontAtlas
+    DearImGui.Internal.Text
+    DearImGui.Raw
+    DearImGui.Raw.DrawList
+    DearImGui.Raw.Font
+    DearImGui.Raw.Font.Config
+    DearImGui.Raw.Font.GlyphRanges
+    DearImGui.Raw.IO
+    DearImGui.Raw.ListClipper
+    DearImGui.Raw.Context
+  other-modules:
+    DearImGui.Enums
+    DearImGui.Structs
+  cxx-options: -std=c++11
   cxx-sources:
     imgui/imgui.cpp
     imgui/imgui_demo.cpp
     imgui/imgui_draw.cpp
     imgui/imgui_tables.cpp
     imgui/imgui_widgets.cpp
-  cxx-options:
-    -std=c++11
-  extra-libraries:
-    stdc++
+  if impl(ghc >= 9.4)
+    build-depends: system-cxx-std-lib
+  else
+    extra-libraries: stdc++
   include-dirs:
     imgui
   build-depends:
-      base
+      dear-imgui-generator
     , containers
+    , managed
     , inline-c
     , inline-c-cpp
     , StateVar
+    , unliftio
+    , vector
+    , text
 
-  if flag(opengl)
+  if os(darwin)
+    ghc-options:
+      -optcxx-std=c++11
+
+  if flag(disable-obsolete)
+    cxx-options: -DIMGUI_DISABLE_OBSOLETE_FUNCTIONS
+
+  if flag(use-wchar32)
+    cxx-options: -DIMGUI_USE_WCHAR32
+    cpp-options: -DIMGUI_USE_WCHAR32
+
+  if flag(use-ImDrawIdx32)
+    cxx-options: "-DImDrawIdx=unsigned int"
+    cpp-options: "-DImDrawIdx=unsigned int"
+
+  if flag(opengl2)
     exposed-modules:
-      DearImGui.OpenGL
+      DearImGui.OpenGL2
     cxx-sources:
       imgui/backends/imgui_impl_opengl2.cpp
-    if os(windows)
-      extra-libraries:
-        opengl32
-    else
-      if os(darwin)
-        frameworks:
-          OpenGL
-      else
-        extra-libraries:
-          GL
+    build-depends:
+      gl
+
+  if flag(opengl3)
+    exposed-modules:
+      DearImGui.OpenGL3
+    cxx-sources:
+      imgui/backends/imgui_impl_opengl3.cpp
+    pkgconfig-depends:
+      glew
 
   if flag(vulkan)
     exposed-modules:
@@ -99,7 +254,7 @@ library
     build-depends:
       sdl2
     cxx-sources:
-      imgui/backends/imgui_impl_sdl.cpp
+      imgui/backends/imgui_impl_sdl2.cpp
 
     if os(windows) || os(darwin)
       extra-libraries:
@@ -108,7 +263,7 @@ library
       pkgconfig-depends:
         sdl2
 
-    if flag(opengl)
+    if flag(opengl2) || flag(opengl3)
       exposed-modules:
         DearImGui.SDL.OpenGL
 
@@ -116,52 +271,153 @@ library
       exposed-modules:
         DearImGui.SDL.Vulkan
 
+    if flag(sdl-renderer)
+      exposed-modules:
+        DearImGui.SDL.Renderer
+      cxx-sources:
+        imgui/backends/imgui_impl_sdlrenderer2.cpp
+
+  if flag(glfw)
+    exposed-modules:
+      DearImGui.GLFW
+    build-depends:
+      GLFW-b,
+      bindings-GLFW
+    cxx-sources:
+      imgui/backends/imgui_impl_glfw.cpp
+
+    if os(linux) || os(darwin)
+      pkgconfig-depends:
+        glfw3
+
+    if flag(opengl2) || flag(opengl3)
+      exposed-modules:
+        DearImGui.GLFW.OpenGL
+
+    if flag(vulkan)
+      exposed-modules:
+        DearImGui.GLFW.Vulkan
+
+library dear-imgui-generator
+  import: common
+  hs-source-dirs: generator
+  exposed-modules:
+      DearImGui.Generator
+    , DearImGui.Generator.Parser
+    , DearImGui.Generator.Tokeniser
+    , DearImGui.Generator.Types
+  build-depends:
+      template-haskell
+        >= 2.15 && < 2.21
+    , containers
+       ^>= 0.6.2.1
+    , directory
+        >= 1.3 && < 1.4
+    , filepath
+        >= 1.4 && < 1.5
+    , inline-c
+        >= 0.9.0.0 && < 0.10
+    , megaparsec
+        >= 9.0 && < 9.4
+    , parser-combinators
+        >= 1.2.0 && < 1.4
+    , scientific
+        >= 0.3.6.2 && < 0.3.8
+    , text
+        >= 1.2.4 && < 2.1
+    , th-lift
+        >= 0.7 && < 0.9
+    , transformers
+        >= 0.5.6 && < 0.7
+    , unordered-containers
+        >= 0.2.11 && < 0.3
 
 executable test
+  import: common, exe-flags
   main-is: Main.hs
   default-language: Haskell2010
-  build-depends: base, sdl2, gl, dear-imgui
-  ghc-options: -Wall
+  if (!flag(examples) || !flag(sdl) || !flag(opengl2))
+    buildable: False
+  else
+    build-depends: base, sdl2, gl, dear-imgui, vector
 
+executable glfw
+  import: common, exe-flags
+  main-is: Main.hs
+  hs-source-dirs: examples/glfw
+  default-language: Haskell2010
+  if (!flag(examples) || !flag(glfw) || !flag(opengl2))
+    buildable: False
+  else
+    build-depends: base, GLFW-b, gl, dear-imgui, managed, text
 
 executable readme
+  import: common, exe-flags
   main-is: Readme.hs
   hs-source-dirs: examples
-  default-language: Haskell2010
-  build-depends: base, sdl2, gl, dear-imgui, managed
-  ghc-options: -Wall
+  build-depends: sdl2, gl, dear-imgui, managed
+  if (!flag(examples) || !flag(sdl) || !flag(opengl2))
+    buildable: False
+
+executable fonts
+  import: common, exe-flags
+  main-is: Main.hs
+  hs-source-dirs: examples/fonts
+  build-depends: sdl2, gl, dear-imgui, managed
+  if (!flag(examples) || !flag(sdl) || !flag(opengl2))
+    buildable: False
+
+executable image
+  import: common, exe-flags
+  main-is: Image.hs
+  hs-source-dirs: examples/sdl
+  build-depends: sdl2, gl, dear-imgui, managed, vector
+  if (!flag(examples) || !flag(sdl) || !flag(opengl3))
+    buildable: False
+
+executable sdlrenderer
+  import: common, exe-flags
+  main-is: Renderer.hs
+  hs-source-dirs: examples/sdl
+  build-depends: sdl2, dear-imgui, managed, text
+  if (!flag(examples) || !flag(sdl) || !flag(sdl-renderer))
+    buildable: False
 
 executable vulkan
+  import: common, exe-flags
   main-is: Main.hs
   other-modules: Attachments, Backend, Input, Util
   hs-source-dirs: examples/vulkan
   default-language: Haskell2010
-  build-depends:
-      dear-imgui
-    , base
-        >= 4.13 && < 4.16
-    , bytestring
-        >= 0.10.10.0 && < 0.12
-    , containers
-       ^>= 0.6.2.1
-    , logging-effect
-       ^>= 1.3.12
-    , resourcet
-       ^>= 1.2.4.2
-    , sdl2
-       ^>= 2.5.3.0
-    , text-short
-       ^>= 0.1.3
-    , transformers
-       ^>= 0.5.6.2
-    , unliftio
-        >= 0.2.13 && < 0.2.15
-    , unliftio-core
-       ^>= 0.2.0.1
-    , vector
-       ^>= 0.12.1.2
-    , vulkan
-       ^>= 3.9
-    , vulkan-utils
-       ^>= 0.4.1
-  ghc-options: -Wall
+  if (!flag(examples) || !flag(sdl) || !flag(vulkan))
+    buildable: False
+  else
+    build-depends:
+        dear-imgui
+      , bytestring
+          >= 0.10.10.0 && < 0.13
+      , containers
+          >= 0.6.2.1 && < 0.7
+      , logging-effect
+          >= 1.3.12 && < 1.5
+      , resourcet
+          >= 1.2.4.2 && < 1.3
+      , sdl2
+          >= 2.5.3.0 && < 2.6
+      , text
+          >= 1.2.4 && < 2.1
+      , transformers
+          >= 0.5.6 && < 0.7
+      , unliftio
+          >= 0.2.13 && < 0.3
+      , unliftio-core
+          >= 0.2.0.1 && < 0.3
+      , vector
+         >= 0.12.1.2 && < 0.14
+      , vulkan
+         >= 3.12
+      , vulkan-utils
+         >= 0.5
+      , VulkanMemoryAllocator
+         >= 0.7.1
+      , JuicyPixels

default.nix

@@ -4,12 +4,12 @@ haskellNix ? (import (import ./nix/sources.nix)."haskell.nix" { })
 # haskell.nix provides access to the nixpkgs pins which are used by our CI,
 # hence you will be more likely to get cache hits when using these.
 # But you can also just use your own, e.g. '<nixpkgs>'.
-, nixpkgsSrc ? haskellNix.sources.nixpkgs-2009
+, nixpkgsSrc ? haskellNix.sources.nixpkgs-2105
 
   # haskell.nix provides some arguments to be passed to nixpkgs, including some
   # patches and also the haskell.nix functionality itself as an overlay.
 , nixpkgsArgs ? haskellNix.nixpkgsArgs
-, compiler-nix-name ? "ghc884"
+, compiler-nix-name ? "ghc8107"
 }:
 let
   pkgs = import nixpkgsSrc nixpkgsArgs;
@@ -20,4 +20,18 @@ in pkgs.haskell-nix.project {
     name = "dear-imgui";
     src = ./.;
   };
+  modules = [ {
+    # This library needs libXext to build, but doesn't explicitly state it in
+    # its .cabal file.
+    packages.bindings-GLFW.components.library.libs =
+      pkgs.lib.mkForce (
+        pkgs.lib.optionals   pkgs.stdenv.isDarwin  (with pkgs.darwin.apple_sdk.frameworks; [ AGL Cocoa OpenGL IOKit Kernel CoreVideo pkgs.darwin.CF ]) ++
+        pkgs.lib.optionals (!pkgs.stdenv.isDarwin) (with pkgs.xorg; [ libXext libXi libXrandr libXxf86vm libXcursor libXinerama pkgs.libGL ])
+      );
+
+    # Depends on libX11 but doesn't state it in the .cabal file.
+    packages.GLFW-b.components.library.libs =
+      with pkgs.xorg;
+      pkgs.lib.mkForce [ libX11 ];
+  } ];
 }

examples/Readme.hs

@@ -1,81 +1,87 @@
 -- NOTE: If this is file is edited, please also copy and paste it into
 -- README.md.
 
-{-# language BlockArguments #-}
-{-# language LambdaCase #-}
 {-# language OverloadedStrings #-}
 
 module Main ( main ) where
 
-import Control.Exception
-import Control.Monad.IO.Class
-import Control.Monad.Managed
 import DearImGui
-import DearImGui.OpenGL
+import DearImGui.OpenGL3
 import DearImGui.SDL
 import DearImGui.SDL.OpenGL
+
 import Graphics.GL
 import SDL
 
+import Control.Monad.Managed
+import Control.Monad.IO.Class ()
+import Control.Monad (when, unless)
+import Control.Exception (bracket, bracket_)
+
 main :: IO ()
 main = do
   -- Initialize SDL
   initializeAll
 
-  runManaged do
-    -- Create a window using SDL. As we're using OpenGL, we need to enable OpenGL too.
-    w <- do
+  runManaged $ do
+    -- Create a window using SDL; as we're using OpenGL, we enable OpenGL too
+    window <- do
       let title = "Hello, Dear ImGui!"
       let config = defaultWindow { windowGraphicsContext = OpenGLContext defaultOpenGL }
       managed $ bracket (createWindow title config) destroyWindow
 
     -- Create an OpenGL context
-    glContext <- managed $ bracket (glCreateContext w) glDeleteContext
-
+    glContext <- managed $ bracket (glCreateContext window) glDeleteContext
     -- Create an ImGui context
     _ <- managed $ bracket createContext destroyContext
 
     -- Initialize ImGui's SDL2 backend
-    _ <- managed_ $ bracket_ (sdl2InitForOpenGL w glContext) sdl2Shutdown
-
+    managed_ $ bracket_ (sdl2InitForOpenGL window glContext) sdl2Shutdown
     -- Initialize ImGui's OpenGL backend
-    _ <- managed_ $ bracket_ openGL2Init openGL2Shutdown
-
-    liftIO $ mainLoop w
+    managed_ $ bracket_ openGL3Init openGL3Shutdown
 
+    liftIO $ mainLoop window
 
 mainLoop :: Window -> IO ()
-mainLoop w = do
-  -- Process the event loop
-  untilNothingM pollEventWithImGui
-
+mainLoop window = unlessQuit $ do
   -- Tell ImGui we're starting a new frame
-  openGL2NewFrame
-  sdl2NewFrame w
+  openGL3NewFrame
+  sdl2NewFrame
   newFrame
 
   -- Build the GUI
-  bracket_ (begin "Hello, ImGui!") end do
+  withWindowOpen "Hello, ImGui!" $ do
     -- Add a text widget
     text "Hello, ImGui!"
 
     -- Add a button widget, and call 'putStrLn' when it's clicked
-    button "Clickety Click" >>= \case
-      False -> return ()
-      True  -> putStrLn "Ow!"
+    button "Clickety Click" >>= \clicked ->
+      when clicked $ putStrLn "Ow!"
 
   -- Show the ImGui demo window
   showDemoWindow
 
   -- Render
   glClear GL_COLOR_BUFFER_BIT
-
   render
-  openGL2RenderDrawData =<< getDrawData
-
-  glSwapWindow w
-
-  mainLoop w
+  openGL3RenderDrawData =<< getDrawData
 
+  glSwapWindow window
+  mainLoop window
   where
-    untilNothingM m = m >>= maybe (return ()) (\_ -> untilNothingM m)
+  -- Process the event loop
+  unlessQuit action = do
+    shouldQuit <- gotQuitEvent
+    unless shouldQuit action
+
+  gotQuitEvent = do
+    ev <- pollEventWithImGui
+
+    case ev of
+      Nothing ->
+        return False
+      Just event ->
+        (isQuit event ||) <$> gotQuitEvent
+
+  isQuit event =
+    eventPayload event == QuitEvent

examples/fonts/Main.hs

@@ -0,0 +1,150 @@
+{-# language BlockArguments #-}
+{-# language LambdaCase #-}
+{-# language OverloadedStrings #-}
+{-# language RecordWildCards #-}
+{-# language NamedFieldPuns #-}
+{-# language DeriveTraversable #-}
+
+{- | Font usage example.
+
+Loads two non-standard fonts
+
+This example uses NotoSansJP-Regular.otf from Google Fonts
+Licensed under the SIL Open Font License, Version 1.1
+https://fonts.google.com/noto/specimen/Noto+Sans+JP
+-}
+
+module Main ( main ) where
+
+import Control.Exception
+import Control.Monad
+import Control.Monad.IO.Class
+import Control.Monad.Managed
+import Data.IORef
+import DearImGui
+import qualified DearImGui.FontAtlas as FontAtlas
+import DearImGui.OpenGL2
+import DearImGui.SDL
+import DearImGui.SDL.OpenGL
+import Graphics.GL
+import SDL
+
+-- Rebuild syntax enables us to keep fonts in any
+-- traversable type, so let's make our life a little easier.
+-- But feel free to use lists or maps.
+data FontSet a = FontSet
+  { droidFont :: a
+  , defaultFont :: a
+  , notoFont :: a
+  }
+  deriving (Functor, Foldable, Traversable)
+
+main :: IO ()
+main = do
+  -- Window initialization is similar to another examples.
+  initializeAll
+  runManaged do
+    window <- do
+      let title = "Hello, Dear ImGui!"
+      let config = defaultWindow { windowGraphicsContext = OpenGLContext defaultOpenGL }
+      managed $ bracket (createWindow title config) destroyWindow
+    glContext <- managed $ bracket (glCreateContext window) glDeleteContext
+    _ <- managed $ bracket createContext destroyContext
+    _ <- managed_ $ bracket_ (sdl2InitForOpenGL window glContext) sdl2Shutdown
+    _ <- managed_ $ bracket_ openGL2Init openGL2Shutdown
+
+    -- We use high-level syntax to build font atlas and
+    -- get handles to use in the main loop.
+    fontSet <- FontAtlas.rebuild FontSet
+      { -- The first mentioned font is loaded first
+        -- and set as a global default.
+        droidFont =
+          FontAtlas.FromTTF
+            "./imgui/misc/fonts/DroidSans.ttf"
+            15
+            Nothing
+            FontAtlas.Cyrillic
+
+        -- You also may use a default hardcoded font for
+        -- some purposes (i.e. as fallback)
+      , defaultFont =
+          FontAtlas.DefaultFont
+
+        -- To optimize atlas size, use ranges builder and
+        -- provide source localization data.
+      , notoFont =
+          FontAtlas.FromTTF
+            "./examples/fonts/NotoSansJP-Regular.otf"
+            20
+            Nothing
+            ( FontAtlas.RangesBuilder $ mconcat
+                [ FontAtlas.addRanges FontAtlas.Latin
+                , FontAtlas.addText "私をクリックしてください"
+                , FontAtlas.addText "こんにちは"
+                ]
+            )
+      }
+
+    liftIO $ do
+      fontFlag <- newIORef False
+      mainLoop window do
+        let FontSet{..} = fontSet
+        withWindowOpen "Hello, ImGui!" do
+          -- To use a font for widget text, you may either put it
+          -- into a 'withFont' block:
+          withFont defaultFont do
+            text "Hello, ImGui!"
+
+          text "Привет, ImGui!"
+
+          -- ...or you can explicitly push and pop a font.
+          -- Though it's not recommended.
+          toggled <- readIORef fontFlag
+
+          when toggled $
+            pushFont notoFont
+
+          -- Some of those are only present in Noto font range
+          -- and will render as `?`s.
+          text "こんにちは, ImGui!"
+
+          let buttonText = if toggled then "私をクリックしてください" else "Click Me!"
+          button buttonText >>= \clicked ->
+            when clicked $
+              modifyIORef' fontFlag not
+
+          when toggled
+            popFont
+
+        showDemoWindow
+
+mainLoop :: Window -> IO () -> IO ()
+mainLoop window frameAction = loop
+  where
+  loop = unlessQuit do
+    openGL2NewFrame
+    sdl2NewFrame
+    newFrame
+
+    frameAction
+
+    glClear GL_COLOR_BUFFER_BIT
+    render
+    openGL2RenderDrawData =<< getDrawData
+    glSwapWindow window
+
+    loop
+
+  unlessQuit action = do
+    shouldQuit <- checkEvents
+    if shouldQuit then pure () else action
+
+  checkEvents = do
+    pollEventWithImGui >>= \case
+      Nothing ->
+        return False
+      Just event ->
+        (isQuit event ||) <$> checkEvents
+
+  isQuit event =
+    SDL.eventPayload event == SDL.QuitEvent

examples/glfw/Main.hs

@@ -0,0 +1,141 @@
+{-# language BlockArguments #-}
+{-# language LambdaCase #-}
+{-# language OverloadedStrings #-}
+{-# language RecordWildCards #-}
+
+module Main ( main ) where
+
+import Control.Exception
+import Control.Monad
+import Control.Monad.IO.Class
+import Control.Monad.Managed
+import Data.Bits ((.|.))
+import Data.IORef
+import Data.List (sortBy)
+import Data.Foldable (traverse_)
+import Data.Text (Text, pack)
+
+import DearImGui
+import DearImGui.OpenGL2
+import DearImGui.GLFW
+import DearImGui.GLFW.OpenGL
+import Graphics.GL
+import Graphics.UI.GLFW (Window)
+import qualified Graphics.UI.GLFW as GLFW
+
+main :: IO ()
+main = do
+  initialised <- GLFW.init
+  unless initialised $ error "GLFW init failed"
+
+  runManaged $ do
+    mwin <- managed $ bracket
+      (GLFW.createWindow 800 600 "Hello, Dear ImGui!" Nothing Nothing)
+      (maybe (return ()) GLFW.destroyWindow)
+    case mwin of
+      Just win -> do
+        liftIO $ do
+          GLFW.makeContextCurrent (Just win)
+          GLFW.swapInterval 1
+
+        -- Create an ImGui context
+        _ <- managed $ bracket createContext destroyContext
+
+        -- Initialize ImGui's GLFW backend
+        _ <- managed_ $ bracket_ (glfwInitForOpenGL win True) glfwShutdown
+
+        -- Initialize ImGui's OpenGL backend
+        _ <- managed_ $ bracket_ openGL2Init openGL2Shutdown
+
+        tableRef <- liftIO $ newIORef
+          [ (1,  "foo")
+          , (2,  "bar")
+          , (3,  "baz")
+          , (10, "spam")
+          , (11, "spam")
+          , (12, "spam")
+          ]
+
+        liftIO $ mainLoop win tableRef
+      Nothing -> do
+        error "GLFW createWindow failed"
+
+  GLFW.terminate
+
+mainLoop :: Window -> IORef [(Integer, Text)] -> IO ()
+mainLoop win tableRef = do
+  -- Process the event loop
+  GLFW.pollEvents
+  close <- GLFW.windowShouldClose win
+  unless close do
+
+    -- Tell ImGui we're starting a new frame
+    openGL2NewFrame
+    glfwNewFrame
+    newFrame
+
+    -- Build the GUI
+    bracket_ (begin "Hello, ImGui!") end do
+      -- Add a text widget
+      text "Hello, ImGui!"
+
+      -- Add a button widget, and call 'putStrLn' when it's clicked
+      clicking <- button "Clickety Click"
+      when clicking $
+        putStrLn "Ow!"
+      itemContextPopup do
+        text "pop!"
+        button "ok" >>= \clicked ->
+          when clicked $
+            closeCurrentPopup
+
+      newLine
+
+      mkTable tableRef
+
+    -- Render
+    glClear GL_COLOR_BUFFER_BIT
+
+    render
+    openGL2RenderDrawData =<< getDrawData
+
+    GLFW.swapBuffers win
+
+    mainLoop win tableRef
+
+mkTable :: IORef [(Integer, Text)] -> IO ()
+mkTable tableRef =
+  withTableOpen sortable "MyTable" 3 $ do
+    tableSetupColumn "Hello"
+    tableSetupColumnWith defTableColumnOptions "World"
+
+    withSortableTable \isDirty sortSpecs ->
+      when (isDirty && not (null sortSpecs)) do
+        -- XXX: do your sorting & cache it. Dont sort every frame.
+        putStrLn "So dirty!"
+        print sortSpecs
+        modifyIORef' tableRef . sortBy $
+          foldMap mkCompare sortSpecs
+
+    tableHeadersRow
+    readIORef tableRef >>=
+      traverse_ \(ix, title) -> do
+        tableNextRow
+        tableNextColumn $ text (pack $ show ix)
+        tableNextColumn $ text title
+        tableNextColumn $ void (button "♥")
+  where
+    mkCompare TableSortingSpecs{..} a b =
+      let
+        dir = if tableSortingReverse then flip else id
+      in
+        case tableSortingColumn of
+          0 -> dir compare (fst a) (fst b)
+          1 -> dir compare (snd a) (snd b)
+          _ -> EQ
+
+    sortable = defTableOptions
+      { tableFlags =
+          ImGuiTableFlags_Sortable .|.
+          ImGuiTableFlags_SortMulti
+      }

examples/sdl/Image.hs

@@ -0,0 +1,195 @@
+{-# language BlockArguments #-}
+{-# language LambdaCase #-}
+{-# language OverloadedStrings #-}
+
+{- | Drawing an DearImGui image using OpenGL textures.
+
+https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples
+-}
+
+module Main ( main ) where
+
+import Control.Exception
+import Control.Monad.IO.Class (MonadIO(..))
+import Control.Monad.Managed (managed, managed_, runManaged)
+import DearImGui
+import qualified DearImGui.Raw as Raw
+import qualified DearImGui.Raw.DrawList as DrawList
+import DearImGui.OpenGL3
+import DearImGui.SDL
+import DearImGui.SDL.OpenGL
+import Graphics.GL
+import qualified SDL as SDL
+
+--  For the texture creation
+import Foreign
+import qualified Data.Vector.Storable as VS
+
+data Texture = Texture
+  { textureID     :: GLuint
+  , textureWidth  :: GLsizei
+  , textureHeight :: GLsizei
+  }
+  deriving (Show)
+
+textureSize :: Texture -> ImVec2
+textureSize texture =
+  ImVec2
+    (fromIntegral $ textureWidth texture)
+    (fromIntegral $ textureHeight texture)
+
+-- | Create a texture pointer in GL memory.
+create2DTexture :: Int -> Int -> IO Texture
+create2DTexture width height =
+  alloca \ptr -> do
+    glGenTextures 1 ptr
+    tID <- peek ptr
+    return Texture
+      { textureID     = tID
+      , textureWidth  = fromIntegral width
+      , textureHeight = fromIntegral height
+      }
+
+bindTexture :: Texture -> Ptr GLubyte -> IO ()
+bindTexture texture dataPtr = do
+  glEnable GL_TEXTURE_2D
+  glBindTexture GL_TEXTURE_2D (textureID texture)
+
+  glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MIN_FILTER GL_LINEAR
+  glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MAG_FILTER GL_LINEAR
+  glTexParameteri GL_TEXTURE_2D GL_TEXTURE_WRAP_S GL_REPEAT
+  glTexParameteri GL_TEXTURE_2D GL_TEXTURE_WRAP_T GL_REPEAT
+
+  glTexImage2D
+    GL_TEXTURE_2D
+    0
+    GL_RGB
+    (textureWidth texture)
+    (textureHeight texture)
+    0
+    GL_RGB
+    GL_UNSIGNED_BYTE
+    (castPtr dataPtr)
+
+fill :: Texture -> (GLubyte, GLubyte, GLubyte) -> VS.Vector GLubyte
+fill texture (r, g, b) =
+  VS.generate
+    (3 * width * height)
+    (\i ->
+        case i `mod` 3 of
+          0 -> r
+          1 -> g
+          2 -> b
+          _ -> error "assert: 3-byte pitch"
+    )
+  where
+    width  = fromIntegral (textureWidth texture)
+    height = fromIntegral (textureHeight texture)
+
+
+main :: IO ()
+main = do
+  -- Initialize SDL
+  SDL.initializeAll
+
+  runManaged do
+    -- Create a window using SDL. As we're using OpenGL, we need to enable OpenGL too.
+    window <- do
+      let title = "Hello, Dear ImGui!"
+      let config = SDL.defaultWindow { SDL.windowGraphicsContext = SDL.OpenGLContext SDL.defaultOpenGL, SDL.windowResizable = True }
+      managed $ bracket (SDL.createWindow title config) SDL.destroyWindow
+
+    -- Create an OpenGL context
+    glContext <- managed $ bracket (SDL.glCreateContext window) SDL.glDeleteContext
+
+    -- Create an ImGui context
+    _dearContext <- managed $ bracket createContext destroyContext
+
+    -- Initialize ImGui's SDL2 backend
+    managed_ $ bracket_ (sdl2InitForOpenGL window glContext) sdl2Shutdown
+
+    -- Initialize ImGui's OpenGL backend
+    managed_ $ bracket_ openGL3Init do
+      putStrLn "ImguiOpenGL shut down"
+      openGL3Shutdown
+
+    liftIO do
+      blueish <- create2DTexture 320 240
+      VS.unsafeWith (fill blueish (0x00, 0x7F, 0xFF)) $
+        bindTexture blueish
+
+      pinkish <- create2DTexture 240 320
+      VS.unsafeWith (fill pinkish (0xFF, 0x00, 0x7F)) $
+        bindTexture pinkish
+
+      err <- glGetError
+      putStrLn $ "Error-code: " ++ show err
+
+      print (blueish, pinkish)
+      mainLoop window (blueish, pinkish) False
+
+mainLoop :: SDL.Window -> (Texture, Texture) -> Bool -> IO ()
+mainLoop window textures flag = unlessQuit do
+  -- Tell ImGui we're starting a new frame
+  openGL3NewFrame
+  sdl2NewFrame
+  newFrame
+
+  let texture = if flag then fst textures else snd textures
+  -- Drawing images require some backend-specific code.
+  -- Meanwhile, we have to deal with raw bindings.
+  let openGLtextureID = intPtrToPtr $ fromIntegral $ textureID texture
+
+  -- Build the GUI
+  clicked <- withWindow "Image example" \open ->
+    if open then do
+      text "That's an image, click it"
+      newLine
+
+      -- Using imageButton
+      Foreign.with (textureSize texture) \sizePtr ->
+        Foreign.with (ImVec2 0 0) \uv0Ptr ->
+          Foreign.with (ImVec2 1 1) \uv1Ptr ->
+            Foreign.with (ImVec4 1 1 1 1) \tintColPtr ->
+              Foreign.with (ImVec4 1 1 1 1) \bgColPtr ->
+                Raw.imageButton openGLtextureID sizePtr uv0Ptr uv1Ptr (-1) bgColPtr tintColPtr
+    else
+      pure False
+
+  -- Using DrawList
+  bg <- getBackgroundDrawList
+  Foreign.with (ImVec2 100 100) \pMin ->
+    Foreign.with (ImVec2 200 200) \pMax ->
+      Foreign.with (ImVec2 0.25 0.25) \uvMin ->
+        Foreign.with (ImVec2 0.75 0.75) \uvMax ->
+          DrawList.addImageRounded
+            bg
+            openGLtextureID
+            pMin pMax uvMin uvMax
+            (Raw.imCol32 0 255 0 0xFF) -- Extract green channel
+            32 ImDrawFlags_RoundCornersBottom
+
+  -- Render
+  glClear GL_COLOR_BUFFER_BIT
+
+  DearImGui.render
+  DearImGui.getDrawData >>= openGL3RenderDrawData
+
+  SDL.glSwapWindow window
+
+  mainLoop window textures (flag /= clicked)
+
+  where
+    unlessQuit action = do
+      shouldQuit <- checkEvents
+      if shouldQuit then pure () else action
+
+    checkEvents = do
+      pollEventWithImGui >>= \case
+        Nothing ->
+          return False
+        Just event ->
+          (isQuit event ||) <$> checkEvents
+
+    isQuit event =
+      SDL.eventPayload event == SDL.QuitEvent

examples/sdl/Renderer.hs

@@ -0,0 +1,146 @@
+{-# language BlockArguments #-}
+{-# language LambdaCase #-}
+{-# language OverloadedStrings #-}
+
+-- | Port of [example_sdl2_sdlrenderer2](https://github.com/ocornut/imgui/blob/54c1bdecebf3c9bb9259c07c5f5666bb4bd5c3ea/examples/example_sdl2_sdlrenderer2/main.cpp).
+--
+-- Minor differences:
+-- - No changing of the clear color via @ImGui::ColorEdit3@ as a Haskell binding
+-- doesn't yet exist for this function.
+-- - No high DPI renderer scaling as this seems to be in flux [upstream](https://github.com/ocornut/imgui/issues/6065)
+
+module Main ( main ) where
+
+import Control.Exception (bracket, bracket_)
+import Control.Monad.IO.Class (MonadIO(liftIO))
+import Control.Monad.Managed (managed, managed_, runManaged)
+import Data.IORef (IORef, newIORef)
+import Data.Text (pack)
+import DearImGui
+import DearImGui.SDL (pollEventWithImGui, sdl2NewFrame, sdl2Shutdown)
+import DearImGui.SDL.Renderer
+  ( sdl2InitForSDLRenderer, sdlRendererInit, sdlRendererNewFrame, sdlRendererRenderDrawData
+  , sdlRendererShutdown
+  )
+import SDL (V4(V4), ($=), ($~), get)
+import Text.Printf (printf)
+import qualified SDL
+
+
+main :: IO ()
+main = do
+  -- Initialize SDL2
+  SDL.initializeAll
+
+  runManaged do
+    -- Create a window using SDL2
+    window <- do
+      let title = "ImGui + SDL2 Renderer"
+      let config = SDL.defaultWindow
+            { SDL.windowInitialSize = SDL.V2 1280 720
+            , SDL.windowResizable = True
+            , SDL.windowPosition = SDL.Centered
+            }
+      managed $ bracket (SDL.createWindow title config) SDL.destroyWindow
+
+    -- Create an SDL2 renderer
+    renderer <- managed do
+      bracket
+        (SDL.createRenderer window (-1) SDL.defaultRenderer)
+        SDL.destroyRenderer
+
+    -- Create an ImGui context
+    _ <- managed $ bracket createContext destroyContext
+
+    -- Initialize ImGui's SDL2 backend
+    _ <- managed_ do
+      bracket_ (sdl2InitForSDLRenderer window renderer) sdl2Shutdown
+
+    -- Initialize ImGui's SDL2 renderer backend
+    _ <- managed_ $ bracket_ (sdlRendererInit renderer) sdlRendererShutdown
+
+    liftIO $ mainLoop renderer
+
+
+mainLoop :: SDL.Renderer -> IO ()
+mainLoop renderer = do
+  refs <- newRefs
+  go refs
+  where
+  go refs = unlessQuit do
+    -- Tell ImGui we're starting a new frame
+    sdlRendererNewFrame
+    sdl2NewFrame
+    newFrame
+
+    -- Show the ImGui demo window
+    get (refsShowDemoWindow refs) >>= \case
+      False -> pure ()
+      True -> showDemoWindow
+
+    withWindowOpen "Hello, world!" do
+      text "This is some useful text."
+      _ <- checkbox "Demo Window" $ refsShowDemoWindow refs
+      _ <- checkbox "Another Window" $ refsShowAnotherWindow refs
+      _ <- sliderFloat "float" (refsFloat refs) 0 1
+
+      button "Button" >>= \case
+        False -> pure ()
+        True -> refsCounter refs $~ succ
+      sameLine
+      counter <- get $ refsCounter refs
+      text $ "counter = " <> pack (show counter)
+
+      fr <- framerate
+      text
+        $ pack
+        $ printf "Application average %.3f ms/frame (%.1f FPS)" (1000 / fr) fr
+
+    get (refsShowAnotherWindow refs) >>= \case
+      False -> pure ()
+      True ->
+        withCloseableWindow "Another Window" (refsShowAnotherWindow refs) do
+          text "Hello from another window!"
+          button "Close Me" >>= \case
+            False -> pure ()
+            True -> refsShowAnotherWindow refs $= False
+
+    -- Render
+    SDL.rendererDrawColor renderer $= V4 0 0 0 255
+    SDL.clear renderer
+    render
+    sdlRendererRenderDrawData =<< getDrawData
+    SDL.present renderer
+
+    go refs
+
+  -- Process the event loop
+  unlessQuit action = do
+    shouldQuit <- checkEvents
+    if shouldQuit then pure () else action
+
+  checkEvents = do
+    pollEventWithImGui >>= \case
+      Nothing ->
+        return False
+      Just event ->
+        (isQuit event ||) <$> checkEvents
+
+  isQuit event =
+    SDL.eventPayload event == SDL.QuitEvent
+
+
+data Refs = Refs
+  { refsShowDemoWindow :: IORef Bool
+  , refsShowAnotherWindow :: IORef Bool
+  , refsFloat :: IORef Float
+  , refsCounter :: IORef Int
+  }
+
+newRefs :: IO Refs
+newRefs =
+  Refs
+    <$> newIORef True
+    <*> newIORef False
+    <*> newIORef 0
+    <*> newIORef 0

examples/vulkan/Backend.hs

@@ -44,7 +44,7 @@ import Data.Traversable
 import Data.Word
   ( Word32 )
 import Foreign.C.String
-  ( CString )
+  ( peekCString )
 import Foreign.C.Types
   ( CInt )
 import Foreign.Ptr
@@ -53,8 +53,6 @@ import Foreign.Ptr
 -- bytestring
 import Data.ByteString
   ( ByteString )
-import qualified Data.ByteString.Short as ShortByteString
-  ( packCString )
 
 -- containers
 import qualified Data.Map.Strict as Map
@@ -77,11 +75,13 @@ import qualified SDL
 import qualified SDL.Raw
 import qualified SDL.Video.Vulkan
 
--- text-short
-import Data.Text.Short
-  ( ShortText )
-import qualified Data.Text.Short as ShortText
-  ( intercalate, pack, fromShortByteString, toByteString, unpack )
+-- text
+import Data.Text
+  ( Text )
+import qualified Data.Text as Text
+  ( intercalate, pack, unpack )
+import Data.Text.Encoding
+  ( encodeUtf8 )
 
 -- transformers
 import Control.Monad.IO.Class
@@ -118,7 +118,7 @@ import Attachments
 
 --------------------------------------------------------------------------------
 
-type LogMessage = WithSeverity ShortText
+type LogMessage = WithSeverity Text
 class    ( MonadUnliftIO m, MonadResource m, MonadLog LogMessage m ) => MonadVulkan m
 instance ( MonadUnliftIO m, MonadResource m, MonadLog LogMessage m ) => MonadVulkan m
 
@@ -127,9 +127,9 @@ instance ( MonadUnliftIO m, MonadResource m, MonadLog LogMessage m ) => MonadVul
 
 logHandler :: MonadIO m => LogMessage -> m ()
 logHandler ( WithSeverity sev mess )
-  = liftIO . putStrLn . ShortText.unpack $ showSeverity sev <> " " <> mess
+  = liftIO . putStrLn . Text.unpack $ showSeverity sev <> " " <> mess
 
-showSeverity :: Severity -> ShortText
+showSeverity :: Severity -> Text
 showSeverity Emergency     = "! PANIC !"
 showSeverity Alert         = "! ALERT !"
 showSeverity Critical      = "! CRIT !"
@@ -190,9 +190,9 @@ initialiseVulkanContext instanceType appName ( VulkanRequirements { instanceRequ
   device <- logDebug "Creating logical device" *>
     Vulkan.Utils.createDeviceFromRequirements swapchainDeviceRequirements [] physicalDevice deviceCreateInfo
   queue  <- Vulkan.getDeviceQueue device ( fromIntegral queueFamily ) 0
-  
+
   pure ( VulkanContext { .. } )
-  
+
 
 
 vulkanInstanceInfo
@@ -206,7 +206,7 @@ vulkanInstanceInfo appName = do
   let
     validationLayer :: Maybe ValidationLayerName
     validationLayer
-      = coerce 
+      = coerce
       . foldMap
         (  (  Vulkan.layerName :: Vulkan.LayerProperties -> ByteString )
         >>> \case
@@ -244,7 +244,7 @@ vulkanInstanceInfo appName = do
 
   case validationLayer of
     Nothing -> logInfo "Validation layer unavailable. Is the Vulkan SDK installed?"
-    Just _  -> logInfo ( "Enabled validation layers " <> ShortText.pack ( show enabledLayers ) )
+    Just _  -> logInfo ( "Enabled validation layers " <> Text.pack ( show enabledLayers ) )
 
   pure createInfo
 
@@ -305,26 +305,23 @@ initialiseWindow ( WindowInfo { height, width, windowName, mouseMode } ) = do
   void ( SDL.setMouseLocationMode mouseMode )
   window           <- logDebug "Creating SDL window"           *> createWindow width height windowName
   neededExtensions <- logDebug "Loading needed extensions"     *> SDL.Video.Vulkan.vkGetInstanceExtensions window
-  extensionNames   <- traverse ( liftIO . peekCString ) neededExtensions
-  logInfo $ "Needed instance extensions are: " <> ShortText.intercalate ", " extensionNames
-  pure ( window, map ShortText.toByteString extensionNames )
-
-peekCString :: CString -> IO ShortText
-peekCString = fmap ( fromMaybe "???" . ShortText.fromShortByteString ) . ShortByteString.packCString
+  extensionNames   <- traverse ( liftIO . fmap fromString . peekCString ) neededExtensions
+  logInfo $ "Needed instance extensions are: " <> Text.intercalate ", " extensionNames
+  pure ( window, map encodeUtf8 extensionNames )
 
 data WindowInfo
   = WindowInfo
   { width      :: CInt
   , height     :: CInt
-  , windowName :: ShortText
+  , windowName :: Text
   , mouseMode  :: SDL.LocationMode
   }
 
-createWindow :: MonadVulkan m => CInt -> CInt -> ShortText -> m SDL.Window
+createWindow :: MonadVulkan m => CInt -> CInt -> Text -> m SDL.Window
 createWindow x y title =
   snd <$> ResourceT.allocate
     ( SDL.createWindow
-              ( fromString ( ShortText.unpack title ) )
+              ( fromString ( Text.unpack title ) )
               SDL.defaultWindow
                 { SDL.windowGraphicsContext = SDL.VulkanContext
                 , SDL.windowInitialSize     = SDL.V2 x y
@@ -374,11 +371,10 @@ chooseSwapchainFormat
 
       case sortOn ( Down . score ) ( Boxed.Vector.toList surfaceFormats ) of
         [] -> error "No formats found."
-        ( best : _ )
-          | Vulkan.FORMAT_UNDEFINED <- ( Vulkan.format :: Vulkan.SurfaceFormatKHR -> Vulkan.Format ) best
-            -> pure preferredFormat
-          | otherwise
-            -> pure best
+        Vulkan.SurfaceFormatKHR{format=Vulkan.FORMAT_UNDEFINED} : _rest ->
+          pure preferredFormat
+        best : _rest
+          -> pure best
 
     where
       match :: Eq a => a -> a -> Int
@@ -405,21 +401,14 @@ createSwapchain physicalDevice device surface surfaceFormat imageUsage imageCoun
 
   surfaceCapabilities <- Vulkan.getPhysicalDeviceSurfaceCapabilitiesKHR physicalDevice ( Vulkan.SurfaceKHR surface )
 
-  ( _, presentModes ) <- Vulkan.getPhysicalDeviceSurfacePresentModesKHR physicalDevice ( Vulkan.SurfaceKHR surface )
-  
   let
     presentMode :: Vulkan.PresentModeKHR
-    presentMode 
-      | Vulkan.PRESENT_MODE_MAILBOX_KHR `elem` presentModes
-      = Vulkan.PRESENT_MODE_MAILBOX_KHR
-      | otherwise
-      = Vulkan.PRESENT_MODE_FIFO_KHR
+    presentMode =
+      Vulkan.PRESENT_MODE_FIFO_KHR -- run at presentation rate
+      -- Vulkan.PRESENT_MODE_MAILBOX_KHR -- max-FPS alternative for benchmarks, input lag debugging, etc.
 
-    currentExtent :: Vulkan.Extent2D
-    currentExtent = ( Vulkan.currentExtent :: Vulkan.SurfaceCapabilitiesKHR -> Vulkan.Extent2D ) surfaceCapabilities
-
-    currentTransform :: Vulkan.SurfaceTransformFlagBitsKHR
-    currentTransform = ( Vulkan.currentTransform :: Vulkan.SurfaceCapabilitiesKHR -> Vulkan.SurfaceTransformFlagBitsKHR ) surfaceCapabilities
+    Vulkan.SurfaceCapabilitiesKHR{currentExtent, currentTransform} = surfaceCapabilities
+    Vulkan.SurfaceFormatKHR{format=fmt, colorSpace=csp} = surfaceFormat
 
     swapchainCreateInfo :: Vulkan.SwapchainCreateInfoKHR '[]
     swapchainCreateInfo =
@@ -428,8 +417,8 @@ createSwapchain physicalDevice device surface surfaceFormat imageUsage imageCoun
         , Vulkan.flags                 = Vulkan.zero
         , Vulkan.surface               = Vulkan.SurfaceKHR surface
         , Vulkan.minImageCount         = imageCount
-        , Vulkan.imageFormat           = ( Vulkan.format     :: Vulkan.SurfaceFormatKHR -> Vulkan.Format        ) surfaceFormat
-        , Vulkan.imageColorSpace       = ( Vulkan.colorSpace :: Vulkan.SurfaceFormatKHR -> Vulkan.ColorSpaceKHR ) surfaceFormat
+        , Vulkan.imageFormat           = fmt
+        , Vulkan.imageColorSpace       = csp
         , Vulkan.imageExtent           = currentExtent
         , Vulkan.imageArrayLayers      = 1
         , Vulkan.imageUsage            = imageUsage
@@ -494,7 +483,7 @@ simpleRenderPass dev attachments = Vulkan.withRenderPass dev createInfo Nothing
         { Vulkan.next         = ()
         , Vulkan.flags        = Vulkan.zero
         , Vulkan.attachments  = Boxed.Vector.fromList attachmentDescriptions
-        , Vulkan.subpasses    = Boxed.Vector.singleton subpass 
+        , Vulkan.subpasses    = Boxed.Vector.singleton subpass
         , Vulkan.dependencies = Boxed.Vector.fromList [ dependency1, dependency2 ]
         }
 
@@ -591,7 +580,7 @@ createFramebuffer
   -> Vulkan.Extent2D
   -> f Vulkan.ImageView
   -> m ( ResourceT.ReleaseKey, Vulkan.Framebuffer )
-createFramebuffer dev renderPass extent attachments = Vulkan.withFramebuffer dev createInfo Nothing ResourceT.allocate
+createFramebuffer dev renderPass Vulkan.Extent2D{width, height} attachments = Vulkan.withFramebuffer dev createInfo Nothing ResourceT.allocate
   where
     createInfo :: Vulkan.FramebufferCreateInfo '[]
     createInfo =
@@ -600,8 +589,8 @@ createFramebuffer dev renderPass extent attachments = Vulkan.withFramebuffer dev
         , Vulkan.flags       = Vulkan.zero
         , Vulkan.renderPass  = renderPass
         , Vulkan.attachments = Boxed.Vector.fromList . toList $ attachments
-        , Vulkan.width       = ( Vulkan.width  :: Vulkan.Extent2D -> Word32 ) extent
-        , Vulkan.height      = ( Vulkan.height :: Vulkan.Extent2D -> Word32 ) extent
+        , Vulkan.width       = width
+        , Vulkan.height      = height
         , Vulkan.layers      = 1
         }
 

examples/vulkan/Main.hs

@@ -24,7 +24,9 @@ import Control.Arrow
 import Control.Exception
   ( throw )
 import Control.Monad
-  ( unless, void )
+  ( unless, void, when )
+import Data.Bits
+  ( (.|.) )
 import Data.Foldable
   ( traverse_ )
 import Data.String
@@ -62,11 +64,13 @@ import qualified Data.Vector as Boxed
   ( Vector )
 import qualified Data.Vector as Boxed.Vector
   ( (!), head, singleton, unzip )
+import qualified Data.Vector.Storable as Storable.Vector
 
 -- vulkan
 import qualified Vulkan
-import qualified Vulkan.Exception as Vulkan
-import qualified Vulkan.Zero      as Vulkan
+import qualified Vulkan.Exception      as Vulkan
+import qualified Vulkan.Zero           as Vulkan
+import qualified VulkanMemoryAllocator as VMA
 
 -- dear-imgui
 import Attachments
@@ -76,6 +80,13 @@ import qualified DearImGui            as ImGui
 import qualified DearImGui.Vulkan     as ImGui.Vulkan
 import qualified DearImGui.SDL        as ImGui.SDL
 import qualified DearImGui.SDL.Vulkan as ImGui.SDL.Vulkan
+import Util (vmaVulkanFunctions)
+import Foreign (Ptr, castPtr, copyBytes, with, withForeignPtr, wordPtrToPtr)
+import qualified DearImGui.Raw as ImGui.Raw
+import UnliftIO (MonadUnliftIO)
+import qualified Vulkan.CStruct.Extends as Vulkan
+
+import qualified Codec.Picture as Picture
 
 --------------------------------------------------------------------------------
 
@@ -83,6 +94,39 @@ type Handler    = LogMessage -> ResourceT IO ()
 deriving via ( ReaderT Handler (ResourceT IO) )
   instance MonadResource ( LoggingT LogMessage (ResourceT IO) )
 
+gui :: MonadUnliftIO m => (ImGui.Raw.ImVec2, Ptr ()) ->  m ImGui.DrawData
+gui texture = do
+  -- Prepare frame
+  ImGui.Vulkan.vulkanNewFrame
+  ImGui.SDL.sdl2NewFrame
+  ImGui.newFrame
+
+  -- Run your windows
+  ImGui.showDemoWindow
+  ImGui.withWindowOpen "Vulkan demo" do
+    clicked <- liftIO do
+      with (fst texture) \sizePtr ->
+        with (ImGui.Raw.ImVec2 0 0) \uv0Ptr ->
+          with (ImGui.Raw.ImVec2 1 1) \uv1Ptr ->
+            with (ImGui.Raw.ImVec4 1 1 1 1) \tintColPtr ->
+              with (ImGui.Raw.ImVec4 1 1 1 1) \bgColPtr ->
+                ImGui.Raw.imageButton
+                  (snd texture)
+                  sizePtr
+                  uv0Ptr
+                  uv1Ptr
+                  (-1)
+                  bgColPtr
+                  tintColPtr
+
+    when clicked $
+      ImGui.text "clicky click!"
+
+
+  -- Process ImGui state into draw commands
+  ImGui.render
+  ImGui.getDrawData
+
 main :: IO ()
 main = runResourceT . ( `runLoggingT` logHandler ) $ app @( LoggingT LogMessage ( ResourceT IO ) )
 
@@ -157,9 +201,7 @@ app = do
   surfaceCapabilities <- Vulkan.getPhysicalDeviceSurfaceCapabilitiesKHR physicalDevice ( Vulkan.SurfaceKHR surface )
 
   let
-    minImageCount, maxImageCount, imageCount :: Word32
-    minImageCount = ( Vulkan.minImageCount :: Vulkan.SurfaceCapabilitiesKHR -> Word32 ) surfaceCapabilities
-    maxImageCount = ( Vulkan.maxImageCount :: Vulkan.SurfaceCapabilitiesKHR -> Word32 ) surfaceCapabilities
+    Vulkan.SurfaceCapabilitiesKHR{minImageCount, maxImageCount} = surfaceCapabilities
     imageCount
       | maxImageCount == 0 =   minImageCount + 1
       | otherwise          = ( minImageCount + 1 ) `min` maxImageCount
@@ -169,31 +211,30 @@ app = do
 
     swapchainResources :: Maybe SwapchainResources -> m ( m (), SwapchainResources )
     swapchainResources mbOldResources = do
-      ( surfaceFormat, imGuiRenderPass ) <- case mbOldResources of
+      ( colFmt, surfaceFormat, imGuiRenderPass ) <- case mbOldResources of
         Nothing -> do
           logDebug "Choosing swapchain format & color space"
           surfaceFormat <- chooseSwapchainFormat preferredFormat physicalDevice surface
-          let
-            colFmt :: Vulkan.Format
-            colFmt = ( Vulkan.format :: Vulkan.SurfaceFormatKHR -> Vulkan.Format ) surfaceFormat
+          let Vulkan.SurfaceFormatKHR{format=colFmt} = surfaceFormat
           logDebug "Creating Dear ImGui render pass"
           ( _, imGuiRenderPass ) <-
             simpleRenderPass device
               ( noAttachments
                 { colorAttachments = Boxed.Vector.singleton $ presentableColorAttachmentDescription colFmt }
               )
-          pure ( surfaceFormat, imGuiRenderPass )
-        Just oldResources -> pure ( surfaceFormat oldResources, imGuiRenderPass oldResources )
-
-      let
-        colFmt :: Vulkan.Format
-        colFmt = ( Vulkan.format :: Vulkan.SurfaceFormatKHR -> Vulkan.Format ) surfaceFormat
+          pure ( colFmt, surfaceFormat, imGuiRenderPass )
+        Just oldResources -> do
+          let surFmt = surfaceFormat oldResources
+          let Vulkan.SurfaceFormatKHR{format=colFmt} = surFmt
+          pure ( colFmt, surFmt, imGuiRenderPass oldResources )
 
       logDebug "Creating swapchain"
       ( swapchainKey, swapchain, swapchainExtent ) <-
         createSwapchain
-          physicalDevice device
-          surface surfaceFormat
+          physicalDevice
+          device
+          surface
+          surfaceFormat
           surfaceUsage
           imageCount
           ( swapchain <$> mbOldResources )
@@ -261,6 +302,80 @@ app = do
   logDebug "Allocating command buffers"
   commandBuffers <- snd <$> allocatePrimaryCommandBuffers device commandPool imageCount
 
+  logDebug "Allocating VMA"
+  (_key, vma) <- VMA.withAllocator
+    Vulkan.zero
+      { VMA.instance'       = Vulkan.instanceHandle instance'
+      , VMA.device          = Vulkan.deviceHandle device
+      , VMA.physicalDevice  = Vulkan.physicalDeviceHandle physicalDevice
+      , VMA.vulkanFunctions = Just $ vmaVulkanFunctions device instance'
+      }
+    ResourceT.allocate
+
+  logDebug "Loading image data"
+  picture <- liftIO (Picture.readImage "Example.png") >>= either error (pure . Picture.convertRGBA8)
+
+  logDebug "Allocating image"
+  let textureWidth = Picture.imageWidth picture
+  let textureHeight = Picture.imageHeight picture
+
+  (_key, (image, _imageAllocation, _imageAllocationInfo)) <- VMA.withImage
+    vma
+    ( Vulkan.zero
+        { Vulkan.imageType     = Vulkan.IMAGE_TYPE_2D
+        , Vulkan.mipLevels     = 1
+        , Vulkan.arrayLayers   = 1
+        , Vulkan.format        = Vulkan.FORMAT_R8G8B8A8_SRGB
+        , Vulkan.extent        = Vulkan.Extent3D (fromIntegral textureWidth) (fromIntegral textureHeight) 1
+        , Vulkan.tiling        = Vulkan.IMAGE_TILING_OPTIMAL
+        , Vulkan.initialLayout = Vulkan.IMAGE_LAYOUT_UNDEFINED
+        , Vulkan.usage         = Vulkan.IMAGE_USAGE_SAMPLED_BIT .|. Vulkan.IMAGE_USAGE_TRANSFER_DST_BIT
+        , Vulkan.sharingMode   = Vulkan.SHARING_MODE_EXCLUSIVE
+        , Vulkan.samples       = Vulkan.SAMPLE_COUNT_1_BIT
+        }
+    )
+    ( Vulkan.zero
+        { VMA.flags         = Vulkan.zero
+        , VMA.usage         = VMA.MEMORY_USAGE_GPU_ONLY
+        , VMA.requiredFlags = Vulkan.MEMORY_PROPERTY_DEVICE_LOCAL_BIT
+        }
+    )
+    ResourceT.allocate
+
+  let (pictureF, pictureSize) = Storable.Vector.unsafeToForeignPtr0 (Picture.imageData picture)
+
+  let stageBufferCI = Vulkan.zero
+        { Vulkan.size        = fromIntegral pictureSize
+        , Vulkan.usage       = Vulkan.BUFFER_USAGE_TRANSFER_SRC_BIT
+        , Vulkan.sharingMode = Vulkan.SHARING_MODE_EXCLUSIVE
+        }
+  let stageAllocationCI = Vulkan.zero
+        { VMA.flags         = VMA.ALLOCATION_CREATE_MAPPED_BIT
+        , VMA.usage         = VMA.MEMORY_USAGE_CPU_TO_GPU
+        , VMA.requiredFlags = Vulkan.MEMORY_PROPERTY_HOST_VISIBLE_BIT
+        }
+
+  (stageKey, (stage, stageAllocation, stageAllocationInfo)) <- VMA.withBuffer
+    vma
+    stageBufferCI
+    stageAllocationCI
+    ResourceT.allocate
+
+  liftIO $ withForeignPtr pictureF \srcPtr ->
+    copyBytes (VMA.mappedData stageAllocationInfo) (castPtr srcPtr) pictureSize
+
+  VMA.flushAllocation vma stageAllocation 0 Vulkan.WHOLE_SIZE
+
+  logDebug "Allocating sampler"
+  (_key, sampler) <- Vulkan.withSampler device Vulkan.zero Nothing ResourceT.allocate
+  logDebug "Allocating image view"
+  (_key, imageView) <- createImageView
+    device
+    image
+    Vulkan.IMAGE_VIEW_TYPE_2D
+    Vulkan.FORMAT_R8G8B8A8_SRGB
+    Vulkan.IMAGE_ASPECT_COLOR_BIT
+
   -------------------------------------------
   -- Initialise Dear ImGui.
 
@@ -294,23 +409,96 @@ app = do
     logDebug "Creating fence"
     ( fenceKey, fence ) <- createFence device
     logDebug "Allocating one-shot command buffer"
-    ( fontUploadCommandBufferKey, fontUploadCommandBuffer ) <-
+    ( oneshotCommandBufferKey, oneshotCommandBuffer ) <-
       second Boxed.Vector.head <$>
         allocatePrimaryCommandBuffers device commandPool 1
 
     logDebug "Recording one-shot commands"
-    beginCommandBuffer fontUploadCommandBuffer
-    _ <- ImGui.Vulkan.vulkanCreateFontsTexture fontUploadCommandBuffer
-    endCommandBuffer fontUploadCommandBuffer
+    beginCommandBuffer oneshotCommandBuffer
+    _ <- ImGui.Vulkan.vulkanCreateFontsTexture oneshotCommandBuffer
+
+    logDebug "Uploading texture"
+    let textureSubresource = Vulkan.ImageSubresourceRange
+          { Vulkan.aspectMask     = Vulkan.IMAGE_ASPECT_COLOR_BIT
+          , Vulkan.baseMipLevel   = 0
+          , Vulkan.levelCount     = 1
+          , Vulkan.baseArrayLayer = 0
+          , Vulkan.layerCount     = 1
+          }
+
+    let uploadBarrier = Vulkan.zero
+          { Vulkan.srcAccessMask       = Vulkan.zero
+          , Vulkan.dstAccessMask       = Vulkan.ACCESS_TRANSFER_WRITE_BIT
+          , Vulkan.oldLayout           = Vulkan.IMAGE_LAYOUT_UNDEFINED
+          , Vulkan.newLayout           = Vulkan.IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL
+          , Vulkan.srcQueueFamilyIndex = Vulkan.QUEUE_FAMILY_IGNORED
+          , Vulkan.dstQueueFamilyIndex = Vulkan.QUEUE_FAMILY_IGNORED
+          , Vulkan.image               = image
+          , Vulkan.subresourceRange    = textureSubresource
+          } :: Vulkan.ImageMemoryBarrier '[]
+    Vulkan.cmdPipelineBarrier
+      oneshotCommandBuffer
+      Vulkan.PIPELINE_STAGE_TOP_OF_PIPE_BIT
+      Vulkan.PIPELINE_STAGE_TRANSFER_BIT
+      Vulkan.zero
+      mempty
+      mempty
+      (Boxed.Vector.singleton $ Vulkan.SomeStruct uploadBarrier)
+
+    Vulkan.cmdCopyBufferToImage oneshotCommandBuffer stage image Vulkan.IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL $
+      Boxed.Vector.singleton Vulkan.BufferImageCopy
+        { Vulkan.bufferOffset      = 0
+        , Vulkan.bufferRowLength   = Vulkan.zero
+        , Vulkan.bufferImageHeight = Vulkan.zero
+        , Vulkan.imageSubresource = Vulkan.ImageSubresourceLayers
+            { aspectMask     = Vulkan.IMAGE_ASPECT_COLOR_BIT
+            , mipLevel       = 0
+            , baseArrayLayer = 0
+            , layerCount     = 1
+            }
+        , Vulkan.imageOffset = Vulkan.zero
+        , Vulkan.imageExtent = Vulkan.Extent3D
+            { width  = fromIntegral textureWidth
+            , height = fromIntegral textureHeight
+            , depth  = 1
+            }
+        }
+
+    logDebug "Transitioning texture"
+    let transitionBarrier = Vulkan.zero
+          { Vulkan.srcAccessMask       = Vulkan.ACCESS_TRANSFER_WRITE_BIT
+          , Vulkan.dstAccessMask       = Vulkan.ACCESS_SHADER_READ_BIT
+          , Vulkan.oldLayout           = Vulkan.IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL
+          , Vulkan.newLayout           = Vulkan.IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL
+          , Vulkan.srcQueueFamilyIndex = Vulkan.QUEUE_FAMILY_IGNORED
+          , Vulkan.dstQueueFamilyIndex = Vulkan.QUEUE_FAMILY_IGNORED
+          , Vulkan.image               = image
+          , Vulkan.subresourceRange    = textureSubresource
+          } :: Vulkan.ImageMemoryBarrier '[]
+    Vulkan.cmdPipelineBarrier
+      oneshotCommandBuffer
+      Vulkan.PIPELINE_STAGE_TRANSFER_BIT
+      Vulkan.PIPELINE_STAGE_FRAGMENT_SHADER_BIT
+      Vulkan.zero
+      mempty
+      mempty
+      (Boxed.Vector.singleton $ Vulkan.SomeStruct transitionBarrier)
+
+    endCommandBuffer oneshotCommandBuffer
 
     logDebug "Submitting one-shot commands"
-    submitCommandBuffer queue fontUploadCommandBuffer [] [] ( Just fence )
+    submitCommandBuffer queue oneshotCommandBuffer [] [] ( Just fence )
     waitForFences device ( WaitAll [ fence ] )
 
     logDebug "Finished uploading font objects"
     logDebug "Cleaning up one-shot commands"
     ImGui.Vulkan.vulkanDestroyFontUploadObjects
-    traverse_ ResourceT.release [ fenceKey, fontUploadCommandBufferKey ]
+    traverse_ ResourceT.release [ fenceKey, oneshotCommandBufferKey, stageKey ]
+
+    logDebug "Adding imgui texture"
+    Vulkan.DescriptorSet ds <- ImGui.Vulkan.vulkanAddTexture sampler imageView Vulkan.IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL
+    let textureSize = ImGui.Raw.ImVec2 (fromIntegral textureWidth) (fromIntegral textureHeight)
+    let texture = (textureSize, wordPtrToPtr $ fromIntegral ds)
 
     let
       mainLoop :: AppState m -> m ()
@@ -341,12 +529,6 @@ app = do
                 pure ( True, False )
               else
                 handleJust vulkanException ( pure . reloadQuit ) do
-                  ImGui.Vulkan.vulkanNewFrame
-                  ImGui.SDL.sdl2NewFrame window
-                  ImGui.newFrame
-                  ImGui.showDemoWindow
-                  ImGui.render
-                  drawData <- ImGui.getDrawData
                   let
                     commandBuffer :: Vulkan.CommandBuffer
                     commandBuffer = commandBuffers Boxed.Vector.! fromIntegral nextImageIndex
@@ -355,7 +537,10 @@ app = do
                   Vulkan.resetCommandBuffer commandBuffer Vulkan.zero
                   beginCommandBuffer commandBuffer
                   cmdBeginRenderPass commandBuffer imGuiRenderPass framebuffer clearValues swapchainExtent
+
+                  drawData <- gui texture
                   ImGui.Vulkan.vulkanRenderDrawData drawData commandBuffer Nothing
+
                   cmdEndRenderPass commandBuffer
                   endCommandBuffer commandBuffer
                   submitCommandBuffer
@@ -370,7 +555,7 @@ app = do
             freeOldResources
             let
               freeOldResources :: m ()
-              freeOldResources = pure ()    
+              freeOldResources = pure ()
             unless quit $ mainLoop ( AppState {..} )
 
     let

examples/vulkan/Util.hs

@@ -1,4 +1,7 @@
 {-# LANGUAGE BlockArguments      #-}
+{-# LANGUAGE CPP                 #-}
+{-# LANGUAGE NamedFieldPuns      #-}
+{-# LANGUAGE RecordWildCards     #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
 module Util where
@@ -12,6 +15,10 @@ import Data.Functor.Identity
   ( Identity(..) )
 import Data.Traversable
   ( for )
+#if MIN_VERSION_VulkanMemoryAllocator(0,8,0)
+import Foreign
+  ( castFunPtr )
+#endif
 
 -- transformers
 import Control.Monad.Trans.State.Strict
@@ -19,6 +26,16 @@ import Control.Monad.Trans.State.Strict
 import Control.Monad.Trans.Writer.Strict
   ( runWriter, tell )
 
+-- vulkan
+import qualified Vulkan
+#if MIN_VERSION_VulkanMemoryAllocator(0,8,0)
+import qualified Vulkan.Dynamic as VkDynamic
+#endif
+import Vulkan.Zero (zero)
+
+-- VulkanMemoryAllocator
+import qualified VulkanMemoryAllocator as VMA
+
 ---------------------------------------------------------------
 
 iunzipWith
@@ -38,3 +55,19 @@ ifor i0 upd ta f = (`evalState` i0) . getCompose $ result
   where
     result :: Compose (State i) f (t b)
     result = for ta \ a -> ( coerce ( \ i -> ( f i a, upd i ) ) )
+
+vmaVulkanFunctions
+  :: Vulkan.Device
+  -> Vulkan.Instance
+  -> VMA.VulkanFunctions
+#if MIN_VERSION_VulkanMemoryAllocator(0,8,0)
+vmaVulkanFunctions Vulkan.Device{deviceCmds} Vulkan.Instance{instanceCmds} =
+  zero
+    { VMA.vkGetInstanceProcAddr =
+        castFunPtr $ VkDynamic.pVkGetInstanceProcAddr instanceCmds
+    , VMA.vkGetDeviceProcAddr =
+        castFunPtr $ VkDynamic.pVkGetDeviceProcAddr deviceCmds
+    }
+#else
+vmaVulkanFunctions _device _instance = zero
+#endif

generator/DearImGui/Generator.hs

@@ -0,0 +1,191 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+module DearImGui.Generator
+  ( declareEnumerations, enumerationsTypesTable )
+  where
+
+-- base
+import Control.Arrow
+  ( second )
+import Data.Bits
+  ( Bits )
+import Data.Foldable
+  ( toList )
+import qualified Data.List.NonEmpty as NonEmpty
+  ( head )
+import Data.String
+  ( fromString )
+import Data.Traversable
+  ( for )
+import Foreign.Storable
+  ( Storable )
+#if MIN_VERSION_template_haskell(2,18,0)
+import Data.Coerce
+  ( coerce )
+#endif
+
+-- containers
+import Data.Map.Strict
+  ( Map )
+import qualified Data.Map.Strict as Map
+  ( fromList )
+
+-- directory
+import System.Directory
+  ( canonicalizePath )
+
+-- filepath
+import System.FilePath
+  ( takeDirectory )
+
+-- inline-c
+import qualified Language.C.Types as InlineC
+  ( TypeSpecifier(TypeName) )
+
+-- megaparsec
+import qualified Text.Megaparsec as Megaparsec
+
+-- template-haskell
+import qualified Language.Haskell.TH        as TH
+import qualified Language.Haskell.TH.Syntax as TH
+
+-- text
+import qualified Data.Text as Text
+import qualified Data.Text.IO as Text
+  ( readFile )
+
+-- dear-imgui-generator
+import qualified DearImGui.Generator.Parser as Parser
+  ( headers )
+import DearImGui.Generator.Tokeniser
+  ( Tok, tokenise )
+import DearImGui.Generator.Types
+  ( Comment(..), Enumeration(..), Headers(..)
+  , generateNames
+  )
+
+--------------------------------------------------------------------------------
+-- Obtaining parsed header data.
+
+headers :: Headers ( TH.Name, TH.Name )
+headers = $( do
+  currentPath <- TH.loc_filename <$> TH.location
+  basicHeaders <- TH.runIO do
+    headersPath  <- canonicalizePath ( takeDirectory currentPath <> "/../../imgui/imgui.h" )
+    headersSource <- Text.readFile headersPath
+    tokens <- case tokenise headersSource of
+      Left  err  -> error ( "Couldn't tokenise Dear ImGui headers:\n\n" <> show err )
+      Right toks -> pure toks
+    case Megaparsec.parse Parser.headers "" tokens of
+      Left  err -> do
+        let
+          errorPos :: Int
+          errorPos = Megaparsec.errorOffset . NonEmpty.head $ Megaparsec.bundleErrors err
+          prev, rest :: [ Tok ]
+          ( prev, rest ) = second ( take 15 ) . splitAt 5 . drop ( errorPos - 5 ) $ tokens
+        error $
+          "Couldn't parse Dear ImGui headers:\n\n" <>
+          ( unlines ( map Megaparsec.parseErrorPretty . toList $ Megaparsec.bundleErrors err ) ) <> "\n" <>
+          ( unlines ( map show prev ) <> "\n\n" <> unlines ( map show rest ) )
+      Right res -> pure res
+  TH.lift $ generateNames basicHeaders
+  )
+
+--------------------------------------------------------------------------------
+-- Generating TH splices.
+
+enumerationsTypesTable :: Map InlineC.TypeSpecifier ( TH.Q TH.Type )
+enumerationsTypesTable = Map.fromList . map mkTypePair $ enums headers
+  where
+    mkTypePair :: Enumeration ( TH.Name, TH.Name ) -> ( InlineC.TypeSpecifier, TH.Q TH.Type )
+    mkTypePair ( Enumeration { enumName, enumTypeName } ) =
+      ( InlineC.TypeName $ fromString ( Text.unpack enumName )
+      , TH.conT ( fst $ enumTypeName )
+      )
+
+declareEnumerations :: TH.Name -> TH.Name -> TH.Q [ TH.Dec ]
+declareEnumerations finiteEnumName countName = do
+  concat <$> mapM ( declareEnumeration finiteEnumName countName ) ( enums headers )
+
+declareEnumeration :: TH.Name -> TH.Name -> Enumeration ( TH.Name, TH.Name ) -> TH.Q [ TH.Dec ]
+declareEnumeration finiteEnumName countName ( Enumeration {..} ) = do
+  let
+    tyName, conName :: TH.Name
+    ( tyName, conName ) = enumTypeName
+    isFlagEnum :: Bool
+    isFlagEnum = "Flags" `Text.isInfixOf` enumName
+    newtypeCon :: TH.Q TH.Con
+    newtypeCon =
+      TH.normalC conName
+        [ TH.bangType
+          ( TH.bang TH.noSourceUnpackedness TH.noSourceStrictness )
+          ( TH.conT underlyingType )
+        ]
+    classes :: [ TH.Q TH.Type ]
+    classes
+      | isFlagEnum
+      = map TH.conT [ ''Eq, ''Ord, ''Show, ''Storable, ''Bits ]
+      | otherwise
+      = map TH.conT [ ''Eq, ''Ord, ''Show, ''Storable ]
+    derivClause :: TH.Q TH.DerivClause
+    derivClause = TH.derivClause ( Just TH.NewtypeStrategy ) classes
+
+  newtypeDecl <-
+#if MIN_VERSION_template_haskell(2,18,0)
+    ( if   null docs
+      then TH.newtypeD
+      else
+        \ ctx name bndrs kd con derivs ->
+          TH.newtypeD_doc ctx name ( fmap pure bndrs ) ( fmap pure kd ) ( con, Nothing, [] ) derivs
+            ( Just . Text.unpack . Text.unlines . coerce $ docs )
+    )
+#else
+    TH.newtypeD
+#endif
+    ( pure [] ) tyName [] Nothing newtypeCon [ derivClause ]
+
+  mbAddFiniteEnumInst <-
+    if hasExplicitCount
+    then do
+      finiteEnumInst <-
+        TH.instanceD ( pure [] ) ( TH.appT ( TH.conT finiteEnumName ) ( TH.conT tyName ) )
+          [ TH.tySynInstD ( TH.TySynEqn Nothing
+                        <$> TH.appT ( TH.conT countName ) ( TH.conT tyName )
+                        <*> TH.litT ( TH.numTyLit enumSize )
+                          )
+          ]
+      pure ( finiteEnumInst : )
+    else pure id
+
+  synonyms <- for patterns \ ( patternName, patternValue, CommentText _patDoc ) -> do
+    let
+      patNameStr :: String
+      patNameStr = Text.unpack patternName
+    patName   <- TH.newName patNameStr
+    patSynSig <- TH.patSynSigD patName ( TH.conT tyName )
+    pat       <-
+#if MIN_VERSION_template_haskell(2,18,0)
+      ( if   Text.null _patDoc
+        then TH.patSynD
+        else
+          \ nm args dir pat ->
+          TH.patSynD_doc nm args dir pat
+            ( Just $ Text.unpack _patDoc ) []
+      )
+#else
+      TH.patSynD
+#endif
+        patName ( TH.prefixPatSyn [] ) TH.implBidir
+        ( TH.conP conName [ TH.litP $ TH.integerL patternValue ] )
+    pure ( patSynSig, pat )
+
+  pure ( newtypeDecl : mbAddFiniteEnumInst ( unpairs synonyms ) )
+
+unpairs :: [ ( a, a ) ] -> [ a ]
+unpairs [] = []
+unpairs ( ( x, y ) : as ) = x : y : unpairs as

generator/DearImGui/Generator/Parser.hs

@@ -0,0 +1,464 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TemplateHaskellQuotes #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE ViewPatterns #-}
+
+module DearImGui.Generator.Parser
+  ( CustomParseError(..)
+  , headers
+  )
+  where
+
+-- base
+import Control.Applicative
+  ( (<|>), many, optional, some )
+import Control.Monad
+  ( void )
+import Data.Bits
+  ( Bits(shiftL) )
+import Data.Char
+  ( isSpace, toLower )
+import Data.Either
+  ( partitionEithers )
+import Data.Functor
+  ( ($>) )
+import Data.Int
+  ( Int64 )
+import Data.Maybe
+  ( catMaybes, fromMaybe )
+import Foreign.C.Types
+  ( CInt )
+
+-- template-haskell
+import qualified Language.Haskell.TH as TH
+  ( Name )
+
+-- megaparsec
+import Text.Megaparsec
+  ( MonadParsec(..), ShowErrorComponent(..)
+  , (<?>), anySingle, customFailure, single
+  )
+
+-- parser-combinators
+import Control.Applicative.Combinators
+  ( manyTill, option, sepBy1, skipManyTill )
+
+-- scientific
+import Data.Scientific
+  ( floatingOrInteger, toBoundedInteger )
+
+-- text
+import Data.Text
+  ( Text )
+import qualified Data.Text as Text
+  ( all, any, breakOn, drop, dropWhile, dropWhileEnd
+  , length, stripPrefix, unlines, unpack, pack
+  )
+
+-- transformers
+import Control.Monad.Trans.State.Strict
+  ( StateT(..)
+  , get, modify'
+  )
+
+-- unordered-containers
+import Data.HashMap.Strict
+  ( HashMap )
+import qualified Data.HashMap.Strict as HashMap
+  ( fromList, insert, lookup )
+
+-- dear-imgui-generator
+import DearImGui.Generator.Tokeniser
+  ( Tok(..) )
+import DearImGui.Generator.Types
+  ( Comment(..), Enumeration(..), Headers(..) )
+
+import qualified Text.Show as Text
+
+--------------------------------------------------------------------------------
+-- Parse error type.
+
+data CustomParseError
+  = Couldn'tLookupEnumValues
+    { enumName :: !Text
+    , problems :: ![Text]
+    }
+  | MissingForwardDeclaration
+    { enumName :: !Text
+    , library :: HashMap Text ( TH.Name, Comment )
+    }
+  | UnexpectedSection
+    { sectionName :: !Text
+    , problem     :: ![Text]
+    }
+  deriving stock ( Show, Eq, Ord )
+
+instance ShowErrorComponent CustomParseError where
+  showErrorComponent ( Couldn'tLookupEnumValues { enumName, problems } ) = Text.unpack $
+    "Couldn't lookup the following values in enum " <> enumName <> ":\n"
+    <> Text.unlines ( map ( " - "  <> ) problems )
+  showErrorComponent ( MissingForwardDeclaration { enumName, library } ) = Text.unpack $
+    "Missing forward declaration for enum named " <> enumName <> "\n"
+    <> "In Library: " <> Text.pack ( Text.show library)
+  showErrorComponent ( UnexpectedSection { sectionName, problem } ) = Text.unpack $
+    "Unexpected section name.\n\
+    \Expected: " <> sectionName <> "\n\
+    \  Actual: " <> Text.unlines ( map ( " "  <> ) problem )
+
+--------------------------------------------------------------------------------
+-- Parsing headers.
+
+headers :: MonadParsec CustomParseError [Tok] m => m ( Headers () )
+headers = do
+  _ <- skipManyTill anySingle ( namedSection "Header mess" )
+
+  _ <- skipManyTill anySingle ( namedSection "Forward declarations" )
+  ( _structNames, enumNamesAndTypes ) <- forwardDeclarations
+
+  _ <- skipManyTill anySingle ( namedSection "Dear ImGui end-user API functions" )
+
+  _ <- skipManyTill anySingle ( namedSection "Flags & Enumerations" )
+  ( _defines, basicEnums ) <- partitionEithers <$>
+    manyTill
+      (   ( Left  <$> try ignoreDefine )
+      <|> ( Left  <$> try cppConditional )
+      <|> ( Right <$> enumeration enumNamesAndTypes )
+      )
+      ( namedSection "Helpers: Memory allocations macros, ImVector<>" )
+
+  _ <- skipManyTill anySingle ( namedSection "ImGuiStyle" )
+
+  _ <- skipManyTill anySingle ( namedSection "ImGuiIO" )
+
+  _ <- skipManyTill anySingle ( namedSection "Misc data structures" )
+
+  _ <- skipManyTill anySingle ( namedSection "Helpers (ImGuiOnceUponAFrame, ImGuiTextFilter, ImGuiTextBuffer, ImGuiStorage, ImGuiListClipper, Math Operators, ImColor)" )
+
+  _ <- skipManyTill anySingle ( namedSection "Drawing API (ImDrawCmd, ImDrawIdx, ImDrawVert, ImDrawChannel, ImDrawListSplitter, ImDrawListFlags, ImDrawList, ImDrawData)" )
+  skipManyTill anySingle ( try . lookAhead $ many comment *> keyword "enum" )
+  drawingEnums <- many ( enumeration enumNamesAndTypes )
+
+  _ <- skipManyTill anySingle ( namedSection "Font API (ImFontConfig, ImFontGlyph, ImFontAtlasFlags, ImFontAtlas, ImFontGlyphRangesBuilder, ImFont)" )
+  skipManyTill anySingle ( try . lookAhead $ many comment *> keyword "enum" )
+  fontEnums <- many ( enumeration enumNamesAndTypes )
+
+  _ <- skipManyTill anySingle ( namedSection "Viewports" )
+
+  _ <- skipManyTill anySingle ( namedSection "Platform Dependent Interfaces" ) -- XXX: since 1.87
+
+  _ <- skipManyTill anySingle ( namedSection "Obsolete functions and types" )
+
+  let
+    enums :: [ Enumeration () ]
+    enums = basicEnums <> drawingEnums <> fontEnums
+  pure ( Headers { enums } )
+
+--------------------------------------------------------------------------------
+-- Parsing forward declarations.
+
+forwardDeclarations
+  :: MonadParsec CustomParseError [Tok] m
+  => m ( HashMap Text Comment, HashMap Text ( TH.Name, Comment ) )
+forwardDeclarations = do
+  _ <- many comment
+  structs <- many do
+    keyword "struct"
+    structName <- identifier
+    reservedSymbol ';'
+    doc <- comment
+    pure ( structName, doc )
+  _ <- many comment
+  enums <- many do
+    keyword "enum"
+    enumName <- identifier
+    symbol ":"
+    ty <- cTypeName
+    reservedSymbol ';'
+    doc <- commentText <$> comment
+    pure ( enumName, ( ty, CommentText <$> Text.drop 2 . snd $ Text.breakOn "//" doc ) )
+  _ <- many comment
+  typedefs <- many do
+    keyword "typedef"
+    ty <- cTypeName
+    enumName <- identifier
+    reservedSymbol ';'
+    doc <- commentText <$> comment
+    _ <- many comment
+    pure ( enumName, ( ty, CommentText <$> Text.drop 2 . snd $ Text.breakOn "//" doc ) )
+  -- Stopping after simple structs and enums for now.
+  pure ( HashMap.fromList structs, HashMap.fromList (enums <> typedefs) )
+
+cTypeName :: MonadParsec e [Tok] m => m TH.Name
+cTypeName = keyword "int" $> ''CInt
+
+--------------------------------------------------------------------------------
+-- Parsing enumerations.
+
+data EnumState = EnumState
+  { enumValues       :: HashMap Text Integer
+  , currEnumTag      :: Integer
+  , enumSize         :: Integer
+  , hasExplicitCount :: Bool
+  }
+
+enumeration :: MonadParsec CustomParseError [Tok] m => HashMap Text ( TH.Name, Comment ) -> m ( Enumeration () )
+enumeration enumNamesAndTypes = do
+  inlineDocs <- try do
+    inlineDocs <- many comment
+    keyword "enum"
+    pure inlineDocs
+  fullEnumName <- identifier
+  _ <- try $ (symbol ":" >> cTypeName >> pure ()) <|> pure ()
+  let
+    enumName :: Text
+    enumName = Text.dropWhileEnd ( == '_' ) fullEnumName
+    enumTypeName :: ()
+    enumTypeName = ()
+  ( underlyingType, forwardDoc ) <- case HashMap.lookup enumName enumNamesAndTypes of
+    Just res -> pure res
+    Nothing  -> customFailure ( MissingForwardDeclaration { enumName, library=enumNamesAndTypes } )
+  let
+    docs :: [Comment]
+    docs = forwardDoc : CommentText "" : inlineDocs
+  reservedSymbol '{'
+  ( patterns, EnumState { enumSize, hasExplicitCount } ) <-
+    ( `runStateT` EnumState { enumValues = mempty, currEnumTag = 0, enumSize = 0, hasExplicitCount = False } ) $
+      catMaybes
+          <$> many
+               (   some ignoredPatternContent $> Nothing
+               <|> enumerationPattern fullEnumName
+               )
+  reservedSymbol '}'
+  reservedSymbol  ';'
+  pure ( Enumeration { .. } )
+
+ignoredPatternContent :: MonadParsec e [Tok] m => m ()
+ignoredPatternContent = void ( try comment ) <|> cppConditional
+
+enumerationPattern
+  :: MonadParsec CustomParseError [ Tok ] m
+  => Text
+  -> StateT EnumState m ( Maybe ( Text, Integer, Comment ) )
+enumerationPattern enumName = do
+  mbPatNameVal <- patternNameAndValue enumName
+  _ <- optional $ reservedSymbol ','
+  comm <- fromMaybe ( CommentText "" ) <$> optional comment
+  pure $
+    case mbPatNameVal of
+      Nothing                    -> Nothing
+      Just ( patName, patValue ) -> Just ( patName, patValue, comm )
+
+patternNameAndValue
+  :: forall m
+  .  MonadParsec CustomParseError [ Tok ] m
+  => Text
+  -> StateT EnumState m ( Maybe ( Text, Integer ) )
+patternNameAndValue enumName =
+  try do
+      sz <- count
+      modify' ( \ ( EnumState {..} ) -> EnumState { enumSize = sz, hasExplicitCount = True, .. } )
+      pure Nothing
+  <|> do
+        pat@( _, val ) <- value
+        modify' ( \ ( EnumState {..} ) -> EnumState { enumSize = enumSize + 1, currEnumTag = val + 1, .. } )
+        pure ( Just pat )
+  where
+    count :: StateT EnumState m Integer
+    count = do
+      let idName = enumName <> "COUNT"
+      _ <- single ( Identifier idName )
+
+      mbVal <- optional do
+        _ <- reservedSymbol '='
+        EnumState{enumValues} <- get
+        integerExpression enumValues
+
+      countVal <- case mbVal of
+        Nothing -> currEnumTag <$> get
+        Just ct -> pure ct
+
+      modify' ( \ st -> st { enumValues = HashMap.insert idName countVal ( enumValues st ) } )
+      pure countVal
+
+    value :: StateT EnumState m ( Text, Integer )
+    value = do
+      name <- identifier
+      val <- patternRHS
+      modify' ( \ st -> st { enumValues = HashMap.insert name val ( enumValues st ) } )
+      pure ( name, val )
+    patternRHS :: StateT EnumState m Integer
+    patternRHS =
+      ( do
+        reservedSymbol '='
+        EnumState{enumValues} <- get
+        try disjunction <|> try (integerExpression enumValues)
+      )
+      <|> ( currEnumTag <$> get )
+
+    disjunction :: StateT EnumState m Integer
+    disjunction = do
+      initial <- identifier <* symbol "|"
+      ( rest :: [Text] ) <- identifier `sepBy1` symbol "|"
+      let summands = initial : rest
+      valsMap <- enumValues <$> get
+      let
+        res :: Either [ Text ] Integer
+        res = foldr
+          ( \ summand errsOrVal -> case HashMap.lookup summand valsMap of
+            Nothing -> case errsOrVal of { Right _  -> Left [ summand ]; Left errs -> Left ( summand : errs ) }
+            Just v  -> case errsOrVal of { Right v' -> Right ( v + v' ); Left errs -> Left errs }
+          )
+          ( Right 0 )
+          summands
+      case res of
+        Left problems -> customFailure ( Couldn'tLookupEnumValues { enumName, problems } )
+        Right v -> pure v
+
+--------------------------------------------------------------------------------
+-- Simple token parsers.
+
+comment :: MonadParsec e [ Tok ] m => m Comment
+comment = CommentText <$>
+  token ( \ case { Comment comm -> Just comm; _ -> Nothing } ) mempty
+    <?> "comment"
+
+keyword :: MonadParsec e [ Tok ] m => Text -> m ()
+keyword kw = token ( \ case { Keyword kw' | kw == kw' -> Just (); _ -> Nothing } ) mempty
+  <?> ( Text.unpack kw <> " (keyword)" )
+
+identifier :: MonadParsec e [ Tok ] m => m Text
+identifier = token ( \ case { Identifier i -> Just i; _ -> Nothing } ) mempty
+  <?> "identifier"
+
+{-
+prefixedIdentifier :: MonadParsec e [ Tok ] m => Text -> m Text
+prefixedIdentifier prefix =
+  token
+    ( \ case
+      { Identifier i -> Text.dropWhile ( == '_' ) <$> Text.stripPrefix prefix i
+      ; _ -> Nothing
+      }
+    ) mempty
+-}
+
+reservedSymbol :: MonadParsec e [ Tok ] m => Char -> m ()
+reservedSymbol s = token ( \ case { ReservedSymbol s' | s == s' -> Just (); _ -> Nothing } ) mempty
+  <?> ( [s] <> " (reserved symbol)" )
+
+symbol :: MonadParsec e [ Tok ] m => Text -> m ()
+symbol s = token ( \ case { Symbolic s' | s == s' -> Just (); _ -> Nothing } ) mempty
+  <?> ( Text.unpack s <> " (symbol)" )
+
+integerExpression :: MonadParsec e [ Tok ] m => HashMap Text Integer -> m Integer
+integerExpression enums = try integerPower <|> try integerAdd <|> try integerSub <|> integer
+  where
+    integerPower :: MonadParsec e [ Tok ] m => m Integer
+    integerPower = do
+      a <- integer
+      _ <- symbol "<<"
+      i <- integer
+      pure ( a `shiftL` fromIntegral i )
+
+    integerAdd :: MonadParsec e [ Tok ] m => m Integer
+    integerAdd = do
+      a <- integer
+      _ <- symbol "+"
+      i <- integer
+      pure ( a + i )
+
+    integerSub :: MonadParsec e [ Tok ] m => m Integer
+    integerSub = do
+      a <- integer
+      _ <- symbol "-"
+      i <- integer
+      pure ( a - i )
+
+    integer :: forall e m. MonadParsec e [ Tok ] m => m Integer
+    integer =
+      option id mkSign <*>
+        token
+          ( \case
+              Number i suff
+                | Just  _  <- toBoundedInteger @Int64 i
+                , Right i' <- floatingOrInteger @Float @Integer i
+                , not ( Text.any ( (== 'f' ) . toLower ) suff )
+                ->
+                Just i'
+
+              Identifier name ->
+                HashMap.lookup name enums
+
+              _ ->
+                Nothing
+          )
+          mempty
+        <?> "integer"
+      where
+        mkSign :: m ( Integer -> Integer )
+        mkSign = ( symbol "+" $> id ) <|> ( symbol "-" $> negate )
+
+section :: MonadParsec e [ Tok ] m => m [Text]
+section =
+  do
+    sectionText <- try do
+      separator
+      token
+        ( \ case
+          { Comment txt -> fmap ( Text.dropWhile isSpace )
+                         . Text.stripPrefix "[SECTION]"
+                         . Text.dropWhile isSpace
+                         $ txt
+          ; _ -> Nothing
+          }
+        ) mempty
+    rest <- endOfSectionHeader
+    pure ( sectionText : filter ( not . Text.all ( \ c -> c == '-' || isSpace c ) ) rest )
+  <?> "section"
+
+separator :: MonadParsec e [ Tok ] m => m ()
+separator = token
+  ( \ case
+    { Comment hyphens | Text.length hyphens > 10 && Text.all ( == '-') hyphens -> Just ()
+    ; _ -> Nothing
+    }
+  ) mempty
+  <?> "separator"
+
+endOfSectionHeader :: MonadParsec e [ Tok ] m => m [Text]
+endOfSectionHeader =  try ( (:) <$> ( commentText <$> comment ) <*> endOfSectionHeader )
+                  <|> ( separator $> [] )
+
+namedSection :: MonadParsec CustomParseError [ Tok ] m => Text -> m ()
+namedSection sectionName =
+  do
+    sectionTexts <- section
+    case sectionTexts of
+      sectionText : _
+        | Just _ <- Text.stripPrefix sectionName sectionText
+        -> pure ()
+      _ -> customFailure ( UnexpectedSection { sectionName, problem = sectionTexts } )
+  <?> ( "section named " <> Text.unpack sectionName )
+
+cppDirective :: MonadParsec e [Tok] m => ( Text -> Maybe a ) -> m a
+cppDirective f = token ( \case { BeginCPP a -> f a; _ -> Nothing } ) mempty
+
+cppConditional :: MonadParsec e [Tok] m => m ()
+cppConditional = do
+  void $ cppDirective ( \case { "ifdef" -> Just True; "ifndef" -> Just False; _ -> Nothing } )
+  -- assumes no nesting
+  void $ skipManyTill anySingle ( cppDirective ( \case { "endif" -> Just (); _ -> Nothing } ) )
+  void $ skipManyTill anySingle ( single EndCPPLine )
+
+ignoreDefine :: MonadParsec e [Tok] m => m ()
+ignoreDefine = do
+  void $ many comment
+  void $ cppDirective ( \case { "define" -> Just (); _ -> Nothing } )
+  void $ skipManyTill anySingle ( single EndCPPLine )

generator/DearImGui/Generator/Tokeniser.hs

@@ -0,0 +1,197 @@
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE ViewPatterns #-}
+
+module DearImGui.Generator.Tokeniser where
+
+-- base
+import Control.Arrow
+  ( first, second )
+import Control.Applicative
+  ( (<|>), some )
+import Data.Char
+  ( isAlpha, isAlphaNum, isDigit, isPunctuation, isSpace, isSymbol, toLower )
+import Data.Function
+  ( (&) )
+import Data.Functor
+  ( ($>) )
+import Data.Monoid
+  ( Sum(..) )
+
+-- megaparsec
+import Text.Megaparsec
+  ( MonadParsec, VisualStream(..)
+  , chunk, parseMaybe, satisfy, try
+  )
+import Text.Megaparsec.Char.Lexer
+  ( hexadecimal, scientific )
+
+-- parser-combinators
+import Control.Monad.Combinators
+  ( optional )
+
+-- scientific
+import Data.Scientific
+  ( Scientific )
+
+-- text
+import Data.Text
+  ( Text )
+import qualified Data.Text as Text
+  ( break, breakOn, cons, drop, dropWhile
+  , head, last, length
+  , pack, snoc, span, strip, tail, take
+  , uncons, unpack
+  )
+
+-- unordered-containers
+import Data.HashSet
+  ( HashSet )
+import qualified Data.HashSet as HashSet
+  ( fromList, member )
+
+--------------------------------------------------------------------------------
+
+data TokeniserError
+  = Couldn'tParseNumber { problem :: !Text }
+  | UnhandledCase { unhandled :: !( Char, Text ) }
+  deriving stock ( Eq, Ord, Show )
+
+data Tok
+  = Keyword        !Text
+  | ReservedSymbol !Char
+  | Symbolic       !Text
+  | Identifier     !Text
+  | Comment        !Text
+  | Char           !Char
+  | String         !Text
+  | Number         !Scientific !Text
+  | BeginCPP       !Text
+  | EndCPPLine
+  deriving stock ( Show, Eq, Ord )
+
+showToken :: Tok -> String
+showToken = \case
+  Keyword        t -> Text.unpack t
+  ReservedSymbol c -> [c]
+  Symbolic       t -> Text.unpack t
+  Identifier     t -> Text.unpack t
+  Comment        t -> Text.unpack t
+  Char           c -> [c]
+  String         t -> Text.unpack t
+  Number       s t -> show s <> Text.unpack t
+  BeginCPP       t -> "#" <> Text.unpack t
+  EndCPPLine       -> "EndCppLine"
+
+tokenLength :: Tok -> Int
+tokenLength = \case
+  Keyword        t -> Text.length t
+  ReservedSymbol _ -> 1
+  Symbolic       t -> Text.length t
+  Identifier     t -> Text.length t
+  Comment        t -> Text.length t
+  Char           _ -> 1
+  String         t -> Text.length t
+  Number       s t -> length ( show s ) + Text.length t
+  BeginCPP       t -> 1 + Text.length t
+  EndCPPLine       -> length ( "EndCPPLine" :: String )
+
+instance VisualStream [Tok] where
+  showTokens   _ = foldMap showToken
+  tokensLength _ = getSum . foldMap ( Sum . tokenLength )
+
+keywords :: HashSet Text
+keywords = HashSet.fromList
+  [ "auto", "break", "case", "char", "const", "continue", "default", "do", "double"
+  , "else", "enum", "extern", "float", "for", "goto", "if", "inline", "int", "long"
+  , "register", "restrict", "return", "short", "signed", "sizeof", "static", "struct"
+  , "switch", "typedef", "union", "unsigned", "void", "volatile", "while"
+  ]
+
+reservedSymbols :: HashSet Char
+reservedSymbols = HashSet.fromList [ '(', ')', '{', '}', ',', ';', '=', '#' ]
+
+tokenise :: Text -> Either TokeniserError [ Tok ]
+tokenise ( Text.uncons -> Just ( c, cs ) )
+  | isSpace c
+  = tokenise ( Text.dropWhile isSpace cs )
+  | isAlpha c || c == '_'
+  , let
+      this, rest :: Text
+      ( this, rest ) = first ( c `Text.cons` ) $ Text.span ( \ x -> isAlphaNum x || x == '_' ) cs
+  = if this `HashSet.member` keywords
+    then ( Keyword    this : ) <$> tokenise rest
+    else ( Identifier this : ) <$> tokenise rest
+  | isDigit c
+  , let
+      this, rest :: Text
+      ( this, rest ) = continuePastExponent $ first ( c `Text.cons` ) $ Text.span ( \ x -> isAlphaNum x || x == '.' ) cs
+  = case parseMaybe @() parseNumber this of
+      Just numTok -> ( numTok : ) <$> tokenise rest
+      Nothing     -> Left ( Couldn'tParseNumber { problem = this } )
+  | c == '\''
+  , Just ( '\'', rest ) <- Text.uncons ( Text.drop 1 cs )
+  = ( Char ( Text.head cs ) : ) <$> tokenise rest
+  | c == '\"'
+  , let
+      this, rest :: Text
+      ( this, rest ) = second Text.tail $ Text.break ( == '"') cs
+  = ( String this : ) <$> tokenise rest
+  | c == '#'
+  , let
+      directive, line, rest :: Text
+      ( directive, ( line, rest ) )
+        = cs
+        & Text.break ( isSpace )
+        & second ( Text.break ( `elem` [ '\n', '\r' ] ) )
+  = do
+      lineTokens <- tokenise line
+      restTokens <- tokenise rest
+      pure ( ( BeginCPP directive : lineTokens ) <> ( EndCPPLine : restTokens ) )
+  | c `HashSet.member` reservedSymbols
+  = ( ReservedSymbol c : ) <$> tokenise cs
+  | c == '/'
+  = case Text.take 1 cs of
+    "/" ->
+      let
+        comm, rest :: Text
+        ( comm, rest ) = first Text.strip $ Text.break ( `elem` [ '\n', '\r' ] ) ( Text.drop 1 cs )
+      in ( Comment comm : ) <$> tokenise rest
+    "*" ->
+      let
+        comm, rest :: Text
+        ( comm, rest ) = Text.breakOn "*/" ( Text.drop 1 cs )
+      in ( Comment comm : ) <$> tokenise rest
+    _ ->
+      let
+        this, rest :: Text
+        ( this, rest ) = first ( c `Text.cons` ) $ Text.span ( \ x -> x /= '_' && ( isSymbol x || isPunctuation x ) ) cs
+      in ( Symbolic this : ) <$> tokenise rest
+  | isSymbol c || isPunctuation c
+  , let
+      this, rest :: Text
+      ( this, rest ) = first ( c `Text.cons` ) $ Text.span ( \ x -> x /= '_' && ( isSymbol x || isPunctuation x ) ) cs
+  = ( Symbolic this : ) <$> tokenise rest
+  | otherwise
+  = Left $ UnhandledCase { unhandled = ( c, cs ) }
+tokenise _ = Right []
+
+continuePastExponent :: ( Text, Text ) -> ( Text, Text )
+continuePastExponent ( this, rest )
+  | toLower ( Text.last this ) `elem` [ 'e', 'p' ]
+  , Just ( r, rs ) <- Text.uncons rest
+  , r `elem` [ '+', '-' ]
+  , ( this', rest' ) <- Text.span isAlphaNum rs
+  = ( this `Text.snoc` r <> this', rest' )
+  | otherwise
+  = ( this, rest )
+
+parseNumber :: MonadParsec e Text m => m Tok
+parseNumber = try ( chunk "0.f" $> Number 0 "f" ) <|> do
+  value <- try ( chunk "0x" *> hexadecimal ) <|> scientific
+  mbSuffix <- fmap ( maybe "" Text.pack ) . optional . some $ satisfy ( \ s -> toLower s `elem` ( "uflz" :: String ) )
+  pure ( Number value mbSuffix )

generator/DearImGui/Generator/Types.hs

@@ -0,0 +1,65 @@
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DeriveLift #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE TemplateHaskellQuotes #-}
+
+module DearImGui.Generator.Types where
+
+-- base
+import Data.Functor
+  ( (<&>) )
+
+-- template-haskell
+import qualified Language.Haskell.TH        as TH
+import qualified Language.Haskell.TH.Syntax as TH
+
+-- text
+import Data.Text
+  ( Text )
+import qualified Data.Text as Text
+  ( unpack )
+
+-- th-lift
+import Language.Haskell.TH.Lift
+  () -- 'Lift' instance for Name
+
+--------------------------------------------------------------------------------
+
+newtype Comment = CommentText { commentText :: Text }
+  deriving stock   ( Show, TH.Lift )
+  deriving newtype ( Eq, Ord )
+
+data Enumeration typeName
+  = Enumeration
+  { docs             :: ![Comment]
+  , enumName         :: !Text
+  , enumTypeName     :: !typeName
+  , enumSize         :: !Integer
+  , underlyingType   :: !TH.Name
+  , hasExplicitCount :: !Bool
+  , patterns         :: [ ( Text, Integer, Comment ) ]
+  }
+  deriving stock ( Show, TH.Lift )
+
+data Headers typeName
+  = Headers
+  { enums :: [ Enumeration typeName ] }
+  deriving stock ( Show, TH.Lift )
+
+generateNames :: Headers () -> Headers ( TH.Name, TH.Name )
+generateNames ( Headers { enums = basicEnums } ) = Headers { enums = namedEnums }
+  where
+    namedEnums :: [ Enumeration ( TH.Name, TH.Name ) ]
+    namedEnums = basicEnums <&> \ enum@( Enumeration { enumName } ) ->
+      let
+        enumNameStr :: String
+        enumNameStr = Text.unpack enumName
+        tyName, conName :: TH.Name
+        tyName  = TH.mkName enumNameStr
+        conName = TH.mkName enumNameStr
+      in
+        enum { enumTypeName = ( tyName, conName ) }

nix/sources.json

@@ -5,10 +5,10 @@
         "homepage": "https://input-output-hk.github.io/haskell.nix",
         "owner": "input-output-hk",
         "repo": "haskell.nix",
-        "rev": "ef4aef4ce2060dc1a41b2690df1f54f986e0f9ab",
-        "sha256": "0537fbjh4mcnywa33h4hl135kw7i8c0j8qndyzv5i82j7mc8wjvs",
+        "rev": "970c84ad19e84d4ae42075cfe283022394f6effa",
+        "sha256": "01afbcas324n7j2bpfib7b4fazg5y6k7b74803c0i9ayrs6sgav6",
         "type": "tarball",
-        "url": "https://github.com/input-output-hk/haskell.nix/archive/ef4aef4ce2060dc1a41b2690df1f54f986e0f9ab.tar.gz",
+        "url": "https://github.com/input-output-hk/haskell.nix/archive/970c84ad19e84d4ae42075cfe283022394f6effa.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "niv": {
@@ -17,10 +17,10 @@
         "homepage": "https://github.com/nmattia/niv",
         "owner": "nmattia",
         "repo": "niv",
-        "rev": "3cd7914b2c4cff48927e11c216dadfab7d903fe5",
-        "sha256": "1agq4nvbhrylf2s77kb4xhh9k7xcwdwggq764k4jgsbs70py8cw3",
+        "rev": "e0ca65c81a2d7a4d82a189f1e23a48d59ad42070",
+        "sha256": "1pq9nh1d8nn3xvbdny8fafzw87mj7gsmp6pxkdl65w2g18rmcmzx",
         "type": "tarball",
-        "url": "https://github.com/nmattia/niv/archive/3cd7914b2c4cff48927e11c216dadfab7d903fe5.tar.gz",
+        "url": "https://github.com/nmattia/niv/archive/e0ca65c81a2d7a4d82a189f1e23a48d59ad42070.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixpkgs": {

nix/sources.nix

@@ -6,52 +6,63 @@ let
   # The fetchers. fetch_<type> fetches specs of type <type>.
   #
 
-  fetch_file = pkgs: spec:
-    if spec.builtin or true then
-      builtins_fetchurl { inherit (spec) url sha256; }
-    else
-      pkgs.fetchurl { inherit (spec) url sha256; };
+  fetch_file = pkgs: name: spec:
+    let
+      name' = sanitizeName name + "-src";
+    in
+      if spec.builtin or true then
+        builtins_fetchurl { inherit (spec) url sha256; name = name'; }
+      else
+        pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
 
-  fetch_tarball = pkgs: spec:
-    if spec.builtin or true then
-      builtins_fetchTarball { inherit (spec) url sha256; }
-    else
-      pkgs.fetchzip { inherit (spec) url sha256; };
+  fetch_tarball = pkgs: name: spec:
+    let
+      name' = sanitizeName name + "-src";
+    in
+      if spec.builtin or true then
+        builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
+      else
+        pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
 
-  fetch_git = spec:
-    builtins.fetchGit { url = spec.repo; inherit (spec) rev ref; };
+  fetch_git = name: spec:
+    let
+      ref =
+        if spec ? ref then spec.ref else
+          if spec ? branch then "refs/heads/${spec.branch}" else
+            if spec ? tag then "refs/tags/${spec.tag}" else
+              abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!";
+    in
+      builtins.fetchGit { url = spec.repo; inherit (spec) rev; inherit ref; };
 
-  fetch_builtin-tarball = spec:
-    builtins.trace
-      ''
-        WARNING:
-          The niv type "builtin-tarball" will soon be deprecated. You should
-          instead use `builtin = true`.
+  fetch_local = spec: spec.path;
 
-          $ niv modify <package> -a type=tarball -a builtin=true
-      ''
-      builtins_fetchTarball { inherit (spec) url sha256; };
+  fetch_builtin-tarball = name: throw
+    ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`.
+        $ niv modify ${name} -a type=tarball -a builtin=true'';
 
-  fetch_builtin-url = spec:
-    builtins.trace
-      ''
-        WARNING:
-          The niv type "builtin-url" will soon be deprecated. You should
-          instead use `builtin = true`.
-
-          $ niv modify <package> -a type=file -a builtin=true
-      ''
-      (builtins_fetchurl { inherit (spec) url sha256; });
+  fetch_builtin-url = name: throw
+    ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`.
+        $ niv modify ${name} -a type=file -a builtin=true'';
 
   #
   # Various helpers
   #
 
+  # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695
+  sanitizeName = name:
+    (
+      concatMapStrings (s: if builtins.isList s then "-" else s)
+        (
+          builtins.split "[^[:alnum:]+._?=-]+"
+            ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name)
+        )
+    );
+
   # The set of packages used when specs are fetched using non-builtins.
-  mkPkgs = sources:
+  mkPkgs = sources: system:
     let
       sourcesNixpkgs =
-        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) {};
+        import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; };
       hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
       hasThisAsNixpkgsPath = <nixpkgs> == ./.;
     in
@@ -71,14 +82,27 @@ let
 
     if ! builtins.hasAttr "type" spec then
       abort "ERROR: niv spec ${name} does not have a 'type' attribute"
-    else if spec.type == "file" then fetch_file pkgs spec
-    else if spec.type == "tarball" then fetch_tarball pkgs spec
-    else if spec.type == "git" then fetch_git spec
-    else if spec.type == "builtin-tarball" then fetch_builtin-tarball spec
-    else if spec.type == "builtin-url" then fetch_builtin-url spec
+    else if spec.type == "file" then fetch_file pkgs name spec
+    else if spec.type == "tarball" then fetch_tarball pkgs name spec
+    else if spec.type == "git" then fetch_git name spec
+    else if spec.type == "local" then fetch_local spec
+    else if spec.type == "builtin-tarball" then fetch_builtin-tarball name
+    else if spec.type == "builtin-url" then fetch_builtin-url name
     else
       abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}";
 
+  # If the environment variable NIV_OVERRIDE_${name} is set, then use
+  # the path directly as opposed to the fetched source.
+  replace = name: drv:
+    let
+      saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
+      ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
+    in
+      if ersatz == "" then drv else
+        # this turns the string into an actual Nix path (for both absolute and
+        # relative paths)
+        if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
+
   # Ports of functions for older nix versions
 
   # a Nix version of mapAttrs if the built-in doesn't exist
@@ -87,23 +111,37 @@ let
     listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set))
   );
 
+  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
+  range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1);
+
+  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
+  stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
+
+  # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269
+  stringAsChars = f: s: concatStrings (map f (stringToCharacters s));
+  concatMapStrings = f: list: concatStrings (map f list);
+  concatStrings = builtins.concatStringsSep "";
+
+  # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
+  optionalAttrs = cond: as: if cond then as else {};
+
   # fetchTarball version that is compatible between all the versions of Nix
-  builtins_fetchTarball = { url, sha256 }@attrs:
+  builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchTarball;
     in
       if lessThan nixVersion "1.12" then
-        fetchTarball { inherit url; }
+        fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
       else
         fetchTarball attrs;
 
   # fetchurl version that is compatible between all the versions of Nix
-  builtins_fetchurl = { url, sha256 }@attrs:
+  builtins_fetchurl = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchurl;
     in
       if lessThan nixVersion "1.12" then
-        fetchurl { inherit url; }
+        fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
       else
         fetchurl attrs;
 
@@ -115,14 +153,15 @@ let
         then abort
           "The values in sources.json should not have an 'outPath' attribute"
         else
-          spec // { outPath = fetch config.pkgs name spec; }
+          spec // { outPath = replace name (fetch config.pkgs name spec); }
     ) config.sources;
 
   # The "config" used by the fetchers
   mkConfig =
-    { sourcesFile ? ./sources.json
-    , sources ? builtins.fromJSON (builtins.readFile sourcesFile)
-    , pkgs ? mkPkgs sources
+    { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
+    , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
+    , system ? builtins.currentSystem
+    , pkgs ? mkPkgs sources system
     }: rec {
       # The sources, i.e. the attribute set of spec name to spec
       inherit sources;
@@ -130,5 +169,6 @@ let
       # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers
       inherit pkgs;
     };
+
 in
 mkSources (mkConfig {}) // { __functor = _: settings: mkSources (mkConfig settings); }

shell.nix

@@ -9,7 +9,7 @@ in
     # You might want some extra tools in the shell (optional).
 
     # Some common tools can be added with the `tools` argument
-    tools = { cabal = "3.2.0.0"; };
+    tools = { cabal = "3.2.0.0"; haskell-language-server = "latest"; };
 
     # Prevents cabal from choosing alternate plans, so that
     # *all* dependencies are provided by Nix.

src/DearImGui/Context.hs

@@ -1,66 +0,0 @@
-{-# language DuplicateRecordFields #-}
-{-# language NamedFieldPuns #-}
-{-# language OverloadedStrings #-}
-{-# language TemplateHaskell #-}
-
-module DearImGui.Context where
-
-import Language.C.Types
-import Language.C.Inline.Context
-import qualified Data.Map.Strict as Map
-import Foreign
-
-
-data ImVec3 = ImVec3 { x, y, z :: {-# unpack #-} !Float }
-
-
-instance Storable ImVec3 where
-  sizeOf ~ImVec3{x, y, z} = sizeOf x + sizeOf y + sizeOf z
-
-  alignment _ = 0
-
-  poke ptr ImVec3{ x, y, z } = do
-    poke (castPtr ptr `plusPtr` (sizeOf x * 0)) x
-    poke (castPtr ptr `plusPtr` (sizeOf x * 1)) y
-    poke (castPtr ptr `plusPtr` (sizeOf x * 2)) z
-
-  peek ptr = do
-    x <- peek (castPtr ptr                         )
-    y <- peek (castPtr ptr `plusPtr` (sizeOf x * 1))
-    z <- peek (castPtr ptr `plusPtr` (sizeOf x * 2))
-    return ImVec3{ x, y, z }
-
-
-data ImVec4 = ImVec4 { x, y, z, w :: {-# unpack #-} !Float }
-
-
-instance Storable ImVec4 where
-  sizeOf ~ImVec4{x, y, z, w} = sizeOf x + sizeOf y + sizeOf z + sizeOf w
-
-  alignment _ = 0
-
-  poke ptr ImVec4{ x, y, z, w } = do
-    poke (castPtr ptr `plusPtr` (sizeOf x * 0)) x
-    poke (castPtr ptr `plusPtr` (sizeOf x * 1)) y
-    poke (castPtr ptr `plusPtr` (sizeOf x * 2)) z
-    poke (castPtr ptr `plusPtr` (sizeOf x * 3)) w
-
-  peek ptr = do
-    x <- peek (castPtr ptr                         )
-    y <- peek (castPtr ptr `plusPtr` (sizeOf x * 1))
-    z <- peek (castPtr ptr `plusPtr` (sizeOf x * 2))
-    w <- peek (castPtr ptr `plusPtr` (sizeOf x * 3))
-    return ImVec4{ x, y, z, w }
-
-
-data ImGuiContext
-
-
-imguiContext :: Context
-imguiContext = mempty
-  { ctxTypesTable = Map.fromList
-      [ ( TypeName "ImVec3", [t| ImVec3 |] )
-      , ( TypeName "ImVec4", [t| ImVec4 |] )
-      , ( TypeName "ImGuiContext", [t| ImGuiContext |])
-      ]
-  }

src/DearImGui/Enums.hs

@@ -0,0 +1,34 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE TypeFamilies #-}
+
+module DearImGui.Enums where
+
+-- base
+import GHC.Exts
+  ( proxy# )
+import GHC.TypeNats
+  ( Nat, KnownNat, natVal' )
+import Numeric.Natural
+  ( Natural )
+
+-- dear-imgui-generator
+import DearImGui.Generator
+  ( declareEnumerations )
+
+--------------------------------------------------------------------------------
+
+class KnownNat ( Count a ) => FiniteEnum a where
+  type Count a :: Nat
+  count :: Natural
+  count = natVal' @( Count a ) proxy#
+
+declareEnumerations ''FiniteEnum ''Count

src/DearImGui/FontAtlas.hs

@@ -0,0 +1,503 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGui.FontAtlas
+
+Font atlas builder, accompanied with lower-level functions.
+
+@
+import qualified DearImGui.FontAtlas as FontAtlas
+
+prepareAtlas =
+  FontAtlas.rebuild
+    [ FontAtlas.FileTTF "comic-sans-mono.ttf" 13 csOptions csRanges
+    , FontAtlas.Default
+    ]
+  where
+    csOptions = mconcat
+      [ FontAtlas.fontNo 1
+      , FontAtlas.glyphOffset (0, -1)
+      ]
+
+    csRanges = RangeBuilder $ mconcat
+      [ FontAtlas.addText "Hello world"
+      , FontRanges.addChar 'Ꙑ'
+      , FontRanges.addRanges FontRanges.Korean
+      ]
+@
+
+-}
+
+module DearImGui.FontAtlas
+  ( -- * Main types
+    Raw.Font(..)
+  , FontSource(..)
+    -- * Building atlas
+  , rebuild
+    -- ** Configuring sources
+  , ConfigSetup(..)
+  , fontDataOwnedByAtlas
+  , fontNo
+  , sizePixels
+  , oversampleH
+  , oversampleV
+  , pixelSnapH
+  , glyphExtraSpacing
+  , glyphOffset
+  , glyphRanges
+  , glyphMinAdvanceX
+  , glyphMaxAdvanceX
+  , mergeMode
+  , fontBuilderFlags
+  , rasterizerMultiply
+  , ellipsisChar
+
+    -- ** Configuring ranges
+  , Ranges(..)
+  , RangesBuilderSetup(..)
+  , addChar
+  , addText
+  , addRanges
+  , addRangesRaw
+
+  , pattern Latin
+  , pattern Korean
+  , pattern Japanese
+  , pattern ChineseFull
+  , pattern ChineseSimplifiedCommon
+  , pattern Cyrillic
+  , pattern Thai
+  , pattern Vietnamese
+
+    -- * Lower level types and functions
+  -- , Raw.FontConfig(..)
+  -- , Raw.GlyphRanges(..)
+  , build
+  , clear
+  , setupFont
+  , setupRanges
+  , withRanges
+  , withConfig
+  , addFontFromFileTTF
+  , addFontFromFileTTF_
+  )
+  where
+
+-- base
+import Data.Bool (bool)
+import Data.Maybe (fromMaybe)
+import Foreign
+import Foreign.C
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+
+-- managed
+import Control.Monad.Managed
+  ( MonadManaged, managed )
+import qualified Control.Monad.Managed as Managed
+
+-- unlift
+import UnliftIO (MonadUnliftIO)
+import UnliftIO.Exception (bracket)
+
+-- dear-imgui
+import DearImGui.Raw.Font (Font(..))
+import qualified DearImGui.Raw.Font as Raw
+import DearImGui.Raw.Font.Config (FontConfig(..))
+import qualified DearImGui.Raw.Font.Config as FontConfig
+import DearImGui.Raw.Font.GlyphRanges (GlyphRanges(..), GlyphRangesBuilder(..))
+import qualified DearImGui.Raw.Font.GlyphRanges as GlyphRanges
+import DearImGui.Internal.Text (Text)
+import qualified DearImGui.Internal.Text as Text
+
+import DearImGui.Structs (ImVec2(..), ImWchar)
+
+-- | Font setup data
+data FontSource
+  = DefaultFont
+  | FromTTF FilePath Float (Maybe ConfigSetup) Ranges
+  -- TODO: FromMemory
+
+-- | Font config monoid interface to be used in 'FontSource'.
+--
+-- @
+-- mergeMode True <> fontNo 1
+-- @
+newtype ConfigSetup = ConfigSetup
+  { applyToConfig :: FontConfig -> IO ()
+  }
+
+instance Semigroup ConfigSetup where
+  ConfigSetup f <> ConfigSetup g =
+    ConfigSetup \fc -> f fc >> g fc
+instance Monoid ConfigSetup where
+  mempty = ConfigSetup (const mempty)
+
+-- | Glyph ranges settings, from presets to builder configuration.
+data Ranges
+  = RangesRaw GlyphRanges
+  | RangesBuiltin GlyphRanges.Builtin
+  | RangesBuilder RangesBuilderSetup
+
+-- | Basic Latin, Extended Latin
+pattern Latin :: Ranges
+pattern Latin = RangesBuiltin GlyphRanges.Latin
+
+-- | Default + Korean characters
+pattern Korean :: Ranges
+pattern Korean = RangesBuiltin GlyphRanges.Korean
+
+-- | Default + Hiragana, Katakana, Half-Width, Selection of 2999 Ideographs
+pattern Japanese :: Ranges
+pattern Japanese = RangesBuiltin GlyphRanges.Japanese
+
+-- | Default + Half-Width + Japanese Hiragana/Katakana + full set of about 21000 CJK Unified Ideographs
+pattern ChineseFull :: Ranges
+pattern ChineseFull = RangesBuiltin GlyphRanges.ChineseFull
+
+-- | Default + Half-Width + Japanese Hiragana/Katakana + set of 2500 CJK Unified Ideographs for common simplified Chinese
+pattern ChineseSimplifiedCommon :: Ranges
+pattern ChineseSimplifiedCommon = RangesBuiltin GlyphRanges.ChineseSimplifiedCommon
+
+-- | Default + about 400 Cyrillic characters
+pattern Cyrillic :: Ranges
+pattern Cyrillic = RangesBuiltin GlyphRanges.Cyrillic
+
+-- | Default + Thai characters
+pattern Thai :: Ranges
+pattern Thai = RangesBuiltin GlyphRanges.Thai
+
+-- | Default + Vietnamese characters
+pattern Vietnamese :: Ranges
+pattern Vietnamese = RangesBuiltin GlyphRanges.Vietnamese
+
+
+-- | Ranges builder monoid interface to be executed through 'buildRanges'.
+--
+-- @
+-- addRanges FontRanges.DefaultRanges <> addText "Привет"
+-- @
+newtype RangesBuilderSetup = RangesBuilderSetup
+  { applyToBuilder :: GlyphRangesBuilder -> IO ()
+  }
+
+instance Semigroup RangesBuilderSetup where
+  RangesBuilderSetup f <> RangesBuilderSetup g =
+    RangesBuilderSetup \fc -> f fc >> g fc
+
+instance Monoid RangesBuilderSetup where
+  mempty = RangesBuilderSetup (const mempty)
+
+-- | Rebuild font atlas with provided configuration
+-- and return corresponding structure of font handles
+-- to be used with 'withFont'.
+--
+-- Accepts any 'Traversable' instance, so you are free to use
+-- lists, maps or custom structures.
+rebuild :: (MonadIO m, Traversable t) => t FontSource -> m (t Font)
+rebuild sources = liftIO $ Managed.with action pure
+  where
+    action = do
+      clear
+      fonts <- traverse setupFont sources
+      build
+      return fonts
+
+-- | Reset font atlas, clearing internal data
+--
+-- Alias for 'Raw.clearFontAtlas'
+clear :: (MonadIO m) => m ()
+clear = Raw.clearFontAtlas
+
+-- | Build font atlas
+--
+-- Alias for 'Raw.buildFontAtlas'
+build :: (MonadIO m) => m ()
+build = Raw.buildFontAtlas
+
+-- | Load a font from TTF file.
+--
+-- Specify font path and atlas glyph size.
+--
+-- Use 'Raw.addFontDefault' if you want to retain built-in font too.
+--
+-- Call 'build' after adding all the fonts,
+-- particularly if you're loading them from memory or use custom glyphs.
+-- Or stick to `rebuild` function.
+--
+-- Call backend-specific `CreateFontsTexture` before using 'newFrame'.
+addFontFromFileTTF :: MonadIO m
+  => FilePath               -- ^ Font file path
+  -> Float                  -- ^ Font size in pixels
+  -> Maybe FontConfig   -- ^ Configuration data
+  -> Maybe GlyphRanges  -- ^ Glyph ranges to use
+  -> m (Maybe Font)     -- ^ Returns font handle, if added successfully
+addFontFromFileTTF font size config ranges = liftIO do
+  res@(Font ptr) <- withCString font \fontPtr ->
+    Raw.addFontFromFileTTF
+      fontPtr
+      (CFloat size)
+      (fromMaybe (FontConfig nullPtr) config)
+      (fromMaybe (GlyphRanges nullPtr) ranges)
+  pure $
+    if castPtr ptr == nullPtr
+      then Nothing
+      else Just res
+      -- FIXME: turn off asserts, so it would work
+
+addFontFromFileTTF_ :: MonadIO m
+  => FilePath           -- ^ Font file path
+  -> Float              -- ^ Font size in pixels
+  -> m (Maybe Raw.Font) -- ^ Returns font handle, if added successfully
+addFontFromFileTTF_ font size =
+  addFontFromFileTTF font size Nothing Nothing
+
+-- | Load a font with provided configuration, return its handle
+-- and defer range builder and config destructors, if needed.
+setupFont :: (MonadManaged m) => FontSource -> m Font
+setupFont = \case
+  DefaultFont ->
+    Raw.addFontDefault
+  FromTTF path size configSetup ranges -> do
+    glyphRanges' <- setupRanges ranges
+    config <- managed (withConfig configSetup)
+    mFont <- addFontFromFileTTF path size config glyphRanges'
+    case mFont of
+      Nothing ->
+        liftIO . fail $ "Couldn't load font from " <> path
+      Just font ->
+        pure font
+
+-- | Configure glyph ranges with provided configuration, return a handle
+-- and defer builder destructors, if needed.
+setupRanges :: (MonadManaged m) => Ranges -> m (Maybe GlyphRanges)
+setupRanges = \case
+  RangesRaw ranges ->
+    pure $ Just ranges
+  RangesBuiltin builtin ->
+    pure $ GlyphRanges.builtinSetup builtin
+  RangesBuilder settings -> do
+    built <- managed $ withRanges settings
+    pure $ Just built
+
+-- | Perform glyph ranges build based on provided configuration,
+-- and execute a computation with built glyph ranges.
+withRanges :: (MonadUnliftIO m) => RangesBuilderSetup -> (GlyphRanges -> m a) -> m a
+withRanges (RangesBuilderSetup setup) fn =
+  bracket acquire release execute
+  where
+    acquire = do
+      builder <- GlyphRanges.new
+      liftIO $ setup builder
+      rangesVec <- GlyphRanges.buildRangesVector builder
+      return (rangesVec, builder)
+
+    release (rangesVec, builder) = do
+      GlyphRanges.destroyRangesVector rangesVec
+      GlyphRanges.destroy builder
+
+    execute (rangesVec, _) =
+      fn (GlyphRanges.fromRangesVector rangesVec)
+
+-- | Configure font config with provided setup,
+-- and execute a computation with built object.
+-- return its handle and list of resource destructors.
+withConfig :: (MonadUnliftIO m) => Maybe ConfigSetup -> (Maybe FontConfig -> m a) -> m a
+withConfig mSetup action =
+  case mSetup of
+    Nothing ->
+      action Nothing
+    Just (ConfigSetup setup) ->
+      bracket acquire (FontConfig.destroy) (action . Just)
+      where
+        acquire = do
+          config <- FontConfig.new
+          liftIO $ setup config
+          return config
+
+-- | Single Unicode character
+addChar :: ImWchar -> RangesBuilderSetup
+addChar char =
+  RangesBuilderSetup \builder ->
+    GlyphRanges.addChar builder char
+
+-- | UTF-8 string
+addText :: Text -> RangesBuilderSetup
+addText str =
+  RangesBuilderSetup \builder ->
+    Text.withCString str (GlyphRanges.addText builder)
+
+-- | Existing ranges (as is)
+addRangesRaw :: GlyphRanges -> RangesBuilderSetup
+addRangesRaw ranges =
+  RangesBuilderSetup \builder ->
+    GlyphRanges.addRanges builder ranges
+
+-- | Existing ranges (through settings interface)
+addRanges :: Ranges -> RangesBuilderSetup
+addRanges = \case
+  RangesRaw ranges ->
+    addRangesRaw ranges
+  RangesBuilder settings ->
+    settings
+  RangesBuiltin builtin ->
+    addRangesRaw (GlyphRanges.getBuiltin builtin)
+
+-- | TTF/OTF data ownership taken by the container ImFontAtlas (will delete memory itself).
+--
+-- By default, it is @true@
+fontDataOwnedByAtlas :: Bool -> ConfigSetup
+fontDataOwnedByAtlas value =
+  ConfigSetup \fc ->
+    FontConfig.setFontDataOwnedByAtlas fc (bool 0 1 value)
+
+-- | Index of font within TTF/OTF file.
+--
+-- By default, it is @0@
+fontNo :: Int -> ConfigSetup
+fontNo value =
+  ConfigSetup \fc ->
+    FontConfig.setFontNo fc (fromIntegral value)
+
+-- | Size in pixels for rasterizer
+--
+-- More or less maps to the resulting font height.
+--
+-- Implicitly set by @addFont...@ functions.
+sizePixels :: Float -> ConfigSetup
+sizePixels value =
+  ConfigSetup \fc ->
+    FontConfig.setSizePixels fc (CFloat value)
+
+-- | Rasterize at higher quality for sub-pixel positioning.
+--
+-- Note: the difference between 2 and 3 is minimal so you can reduce this to 2 to save memory.
+-- Read https://github.com/nothings/stb/blob/master/tests/oversample/README.md for details.
+--
+-- By default, it is @3@
+oversampleH :: Int -> ConfigSetup
+oversampleH value =
+  ConfigSetup \fc ->
+    FontConfig.setOversampleH fc (fromIntegral value)
+
+-- | Rasterize at higher quality for sub-pixel positioning.
+--
+-- This is not really useful as we don't use sub-pixel positions on the Y axis.
+--
+-- By default, it is @1@
+oversampleV :: Int -> ConfigSetup
+oversampleV value =
+  ConfigSetup \fc ->
+    FontConfig.setOversampleV fc (fromIntegral value)
+
+-- | Align every glyph to pixel boundary.
+--
+-- Useful if you are merging a non-pixel aligned font with the default font.
+-- If enabled, you can set OversampleH/V to 1.
+--
+-- By default, it is @false@
+pixelSnapH :: Bool -> ConfigSetup
+pixelSnapH value =
+  ConfigSetup \fc ->
+    FontConfig.setPixelSnapH fc (bool 0 1 value)
+
+-- | Extra spacing (in pixels) between glyphs.
+--
+-- Only X axis is supported for now.
+--
+-- By default, it is @0, 0@
+glyphExtraSpacing :: (Float, Float) -> ConfigSetup
+glyphExtraSpacing (x, y) =
+  ConfigSetup \fc ->
+    Foreign.with (ImVec2 x y) (FontConfig.setGlyphExtraSpacing fc)
+
+-- | Offset all glyphs from this font input.
+--
+-- By default, it is @0, 0@
+glyphOffset :: (Float, Float) -> ConfigSetup
+glyphOffset (x, y) =
+  ConfigSetup \fc ->
+    Foreign.with (ImVec2 x y) (FontConfig.setGlyphOffset fc)
+
+-- | Pointer to a user-provided list of Unicode range.
+--
+-- 2 values per range, inclusive. Zero-terminated list.
+--
+-- THE ARRAY DATA NEEDS TO PERSIST AS LONG AS THE FONT IS ALIVE.
+--
+-- By default, it is @NULL@
+glyphRanges :: GlyphRanges -> ConfigSetup
+glyphRanges value =
+  ConfigSetup \fc ->
+    FontConfig.setGlyphRanges fc value
+
+-- | Minimum AdvanceX for glyphs.
+--
+-- Set Min to align font icons, set both Min/Max to enforce mono-space font.
+--
+-- By default, it is @0@
+glyphMinAdvanceX :: Float -> ConfigSetup
+glyphMinAdvanceX value =
+  ConfigSetup \fc ->
+    FontConfig.setGlyphMinAdvanceX fc (CFloat value)
+
+-- | Maximum AdvanceX for glyphs.
+--
+-- By default, it is @FLT_MAX@.
+glyphMaxAdvanceX :: Float -> ConfigSetup
+glyphMaxAdvanceX value =
+  ConfigSetup \fc ->
+    FontConfig.setGlyphMaxAdvanceX fc (CFloat value)
+
+-- | Merge into previous ImFont, so you can combine multiple inputs font into one ImFont.
+--
+-- e.g. ASCII font + icons + Japanese glyphs.
+-- You may want to use @GlyphOffset.y@ when merging font of different heights.
+--
+-- By default, it is @false@
+mergeMode :: Bool -> ConfigSetup
+mergeMode value =
+  ConfigSetup \fc ->
+    FontConfig.setMergeMode fc (bool 0 1 value)
+
+-- | Settings for custom font GlyphRanges.
+--
+-- THIS IS BUILDER IMPLEMENTATION DEPENDENT.
+--
+-- By default, it is @0@. Leave it so if unsure.
+fontBuilderFlags :: Int -> ConfigSetup
+fontBuilderFlags value =
+  ConfigSetup \fc ->
+    FontConfig.setFontBuilderFlags fc (fromIntegral value)
+
+-- | Brighten (>1.0f) or darken (<1.0f) font output.
+--
+-- Brightening small fonts may be a good workaround to make them more readable.
+--
+-- By default, it is @1.0f@.
+rasterizerMultiply :: Float -> ConfigSetup
+rasterizerMultiply value =
+  ConfigSetup \fc ->
+    FontConfig.setRasterizerMultiply fc (CFloat value)
+
+-- | Explicitly specify unicode codepoint of ellipsis character.
+--
+-- When fonts are being merged first specified ellipsis will be used.
+--
+-- By default, it is @-1@
+ellipsisChar :: ImWchar -> ConfigSetup
+ellipsisChar value =
+  ConfigSetup \fc ->
+    FontConfig.setEllipsisChar fc value

src/DearImGui/GLFW.hs

@@ -0,0 +1,203 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGui.GLFW
+
+GLFW specific functions backend for Dear ImGui.
+
+Modules for initialising a backend with GLFW can be found under the corresponding backend,
+e.g. "DearImGui.GLFW.OpenGL".
+-}
+
+module DearImGui.GLFW (
+    -- ** GLFW
+    glfwNewFrame
+  , glfwShutdown
+
+    -- $callbacks
+  , glfwWindowFocusCallback
+  , glfwCursorEnterCallback
+  , glfwCursorPosCallback
+  , glfwMouseButtonCallback
+  , glfwScrollCallback
+  , glfwKeyCallback
+  , glfwCharCallback
+  , glfwMonitorCallback
+  )
+  where
+
+-- base
+import Foreign
+  ( Ptr, castPtr )
+import Foreign.C.Types
+  ( CInt, CDouble, CUInt )
+import Unsafe.Coerce (unsafeCoerce)
+
+-- bindings-GLFW
+import Bindings.GLFW
+  ( C'GLFWmonitor, C'GLFWwindow )
+
+-- GLFW-b
+import Graphics.UI.GLFW
+  ( Monitor, Window )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+
+
+C.context (Cpp.cppCtx <> C.bsCtx)
+C.include "imgui.h"
+C.include "backends/imgui_impl_glfw.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Wraps @ImGui_ImplGlfw_NewFrame@.
+glfwNewFrame :: MonadIO m => m ()
+glfwNewFrame = liftIO do
+  [C.exp| void { ImGui_ImplGlfw_NewFrame(); } |]
+
+-- $callbacks
+-- == GLFW callbacks
+-- * When calling Init with @install_callbacks=true@:
+--   GLFW callbacks will be installed for you.
+--   They will call user's previously installed callbacks, if any.
+-- * When calling Init with @install_callbacks=false@:
+--   GLFW callbacks won't be installed.
+--   You will need to call those function yourself from your own GLFW callbacks.
+
+-- | Wraps @ImGui_ImplGlfw_Shutdown@.
+glfwShutdown :: MonadIO m => m ()
+glfwShutdown = liftIO do
+  [C.exp| void { ImGui_ImplGlfw_Shutdown(); } |]
+
+glfwWindowFocusCallback :: MonadIO m => Window -> CInt -> m ()
+glfwWindowFocusCallback window focused = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_WindowFocusCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(int focused)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwCursorEnterCallback :: MonadIO m => Window -> CInt -> m ()
+glfwCursorEnterCallback window entered = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_CursorEnterCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(int entered)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwCursorPosCallback :: MonadIO m => Window -> CDouble -> CDouble -> m ()
+glfwCursorPosCallback window x y = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_CursorPosCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(double x),
+      $(double y)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwMouseButtonCallback :: MonadIO m => Window -> CInt -> CInt -> CInt -> m ()
+glfwMouseButtonCallback window button action mods = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_MouseButtonCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(int button),
+      $(int action),
+      $(int mods)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwScrollCallback :: MonadIO m => Window -> CDouble -> CDouble -> m ()
+glfwScrollCallback window xoffset yoffset = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_ScrollCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(double xoffset),
+      $(double yoffset)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwKeyCallback :: MonadIO m => Window -> CInt -> CInt -> CInt -> CInt -> m ()
+glfwKeyCallback window key scancode action mods = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_KeyCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(int key),
+      $(int scancode),
+      $(int action),
+      $(int mods)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwCharCallback :: MonadIO m => Window -> CUInt -> m ()
+glfwCharCallback window c = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_CharCallback(
+      static_cast<GLFWwindow *>(
+        $(void * windowPtr)
+      ),
+      $(unsigned int c)
+    );
+  } |]
+  where
+    windowPtr = castPtr $ unWindow window
+
+glfwMonitorCallback :: MonadIO m => Monitor -> CInt -> m ()
+glfwMonitorCallback monitor event = liftIO do
+  [C.exp| void {
+    ImGui_ImplGlfw_MonitorCallback(
+      static_cast<GLFWmonitor *>(
+        $(void * monitorPtr)
+      ),
+      $(int event)
+    );
+  } |]
+  where
+    monitorPtr = castPtr $ unMonitor monitor
+
+-- | Strip the unpublished newtype wrapper.
+unWindow :: Window -> Ptr C'GLFWwindow
+unWindow = unsafeCoerce
+
+-- | Strip the unpublished newtype wrapper.
+unMonitor :: Monitor -> Ptr C'GLFWmonitor
+unMonitor = unsafeCoerce

src/DearImGui/GLFW/OpenGL.hs

@@ -0,0 +1,61 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGUI.GLFW.OpenGL
+
+Initialising the OpenGL backend for Dear ImGui using GLFW3.
+-}
+
+module DearImGui.GLFW.OpenGL
+  ( glfwInitForOpenGL )
+  where
+
+-- base
+import Data.Bool
+  ( bool )
+import Foreign.C.Types
+  ( CBool )
+import Foreign.Ptr
+  ( Ptr )
+import Unsafe.Coerce
+  ( unsafeCoerce )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+-- GLFW
+import Graphics.UI.GLFW
+  ( Window )
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+
+
+C.context (Cpp.cppCtx <> C.bsCtx)
+C.include "imgui.h"
+C.include "backends/imgui_impl_opengl2.h"
+C.include "backends/imgui_impl_glfw.h"
+C.include "GLFW/glfw3.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Wraps @ImGui_ImplGlfw_InitForOpenGL@.
+glfwInitForOpenGL :: MonadIO m => Window -> Bool -> m Bool
+glfwInitForOpenGL window installCallbacks = liftIO do
+  ( 0 /= ) <$> [C.exp| bool { ImGui_ImplGlfw_InitForOpenGL((GLFWwindow*)$(void* windowPtr), $(bool cInstallCallbacks)) } |]
+  where
+    windowPtr :: Ptr ()
+    windowPtr = unsafeCoerce window
+
+    cInstallCallbacks :: CBool
+    cInstallCallbacks = bool 0 1 installCallbacks

src/DearImGui/GLFW/Vulkan.hs

@@ -0,0 +1,60 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGui.GLFW.Vulkan
+
+Initialising the Vulkan backend for Dear ImGui using GLFW3.
+-}
+
+module DearImGui.GLFW.Vulkan
+  ( glfwInitForVulkan )
+  where
+
+-- base
+import Data.Bool
+  ( bool )
+import Foreign.C.Types
+  ( CBool )
+import Foreign.Ptr
+  ( Ptr )
+import Unsafe.Coerce
+  ( unsafeCoerce )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+-- GLFW
+import Graphics.UI.GLFW
+  ( Window )
+
+-- transformers
+import Control.Monad.IO.Class ( MonadIO, liftIO )
+
+
+C.context Cpp.cppCtx
+C.include "imgui.h"
+C.include "backends/imgui_impl_vulkan.h"
+C.include "backends/imgui_impl_glfw.h"
+C.include "GLFW/glfw3.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Wraps @ImGui_ImplGlfw_InitForVulkan@.
+glfwInitForVulkan :: MonadIO m => Window -> Bool -> m Bool
+glfwInitForVulkan window installCallbacks = liftIO do
+  ( 0 /= ) <$> [C.exp| bool { ImGui_ImplGlfw_InitForVulkan((GLFWwindow*)$(void* windowPtr), $(bool cInstallCallbacks)) } |]
+  where
+    windowPtr :: Ptr ()
+    windowPtr = unsafeCoerce window
+
+    cInstallCallbacks :: CBool
+    cInstallCallbacks = bool 0 1 installCallbacks

src/DearImGui/Internal/Text.hs

@@ -0,0 +1,76 @@
+{-# LANGUAGE CPP #-}
+
+module DearImGui.Internal.Text
+  ( withCString
+  , withCStringOrNull
+  , withCStringLen
+  , withCStringEnd
+  , peekCString
+
+  , Text
+  , pack
+  , unpack
+  ) where
+
+-- base
+import Foreign (nullPtr, plusPtr)
+import Foreign.C.String (CString)
+import qualified GHC.Foreign as Foreign
+import System.IO (utf8)
+
+-- text
+import Data.Text (Text, pack, unpack)
+import Data.Text.Foreign (withCStringLen)
+
+-- unliftio-core
+import UnliftIO (MonadUnliftIO, UnliftIO(..), withUnliftIO)
+
+#if MIN_VERSION_text(2,0,1)
+-- XXX: just wrap the provided combinator
+
+import qualified Data.Text.Foreign as Text
+
+withCString :: MonadUnliftIO m => Text -> (CString -> m a) -> m a
+withCString text action =
+  withUnliftIO $ \(UnliftIO unlift) ->
+    Text.withCString text $ \buf ->
+      unlift $ action buf
+
+#elif MIN_VERSION_text(2,0,0)
+-- XXX: the text is UTF-8, alas no withCString is available
+
+import Data.Text.Foreign (lengthWord8, unsafeCopyToPtr)
+import Data.Word (Word8)
+import Foreign (allocaBytes, castPtr, pokeByteOff)
+
+withCString :: MonadUnliftIO m => Text -> (CString -> m a) -> m a
+withCString t@(Text _arr _off len) action =
+  withUnliftIO $ \(UnliftIO unlift) ->
+    allocaBytes (len + 1) $ \buf -> do
+      unsafeCopyToPtr t buf
+      pokeByteOff buf len (0 :: Word8)
+      unlift $ action (castPtr buf)
+
+#else
+-- XXX: the text is UTF-16, let GHC do it
+
+withCString :: MonadUnliftIO m => Text -> (CString -> m a) -> m a
+withCString t action = do
+  withUnliftIO $ \(UnliftIO unlift) ->
+    Foreign.withCString utf8 (unpack t) $ \textPtr ->
+      unlift $ action textPtr
+
+#endif
+
+peekCString :: CString -> IO Text
+peekCString = fmap pack . Foreign.peekCString utf8
+
+withCStringOrNull :: Maybe Text -> (CString -> IO a) -> IO a
+withCStringOrNull Nothing k  = k nullPtr
+withCStringOrNull (Just s) k = withCString s k
+
+withCStringEnd :: MonadUnliftIO m => Text -> (CString -> CString -> m a) -> m a
+withCStringEnd t action =
+  withUnliftIO $ \(UnliftIO unlift) ->
+    withCStringLen t $ \(textPtr, size) ->
+      unlift $ action textPtr (textPtr `plusPtr` size)

src/DearImGui/OpenGL2.hs

@@ -9,10 +9,10 @@
 {-|
 Module: DearImGui.OpenGL
 
-OpenGL backend for Dear ImGui.
+OpenGL 2 backend for Dear ImGui.
 -}
 
-module DearImGui.OpenGL
+module DearImGui.OpenGL2
   ( openGL2Init
   , openGL2Shutdown
   , openGL2NewFrame

src/DearImGui/OpenGL3.hs

@@ -0,0 +1,69 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGui.OpenGL
+
+OpenGL 3 backend for Dear ImGui.
+-}
+
+module DearImGui.OpenGL3
+  ( openGL3Init
+  , openGL3Shutdown
+  , openGL3NewFrame
+  , openGL3RenderDrawData
+  )
+  where
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+
+-- DearImGui
+import DearImGui
+  ( DrawData(..) )
+
+
+C.context (Cpp.cppCtx <> C.bsCtx)
+C.include "imgui.h"
+C.include "GL/glew.h"
+C.include "backends/imgui_impl_opengl3.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Wraps @ImGui_ImplOpenGL3_Init@.
+openGL3Init :: MonadIO m => m Bool
+openGL3Init = liftIO $
+  ( 0 /= ) <$> [C.block| bool {
+    glewInit();
+    return ImGui_ImplOpenGL3_Init();
+  } |]
+
+
+-- | Wraps @ImGui_ImplOpenGL3_Shutdown@.
+openGL3Shutdown :: MonadIO m => m ()
+openGL3Shutdown = liftIO do
+  [C.exp| void { ImGui_ImplOpenGL3_Shutdown(); } |]
+
+
+-- | Wraps @ImGui_ImplOpenGL3_NewFrame@.
+openGL3NewFrame :: MonadIO m => m ()
+openGL3NewFrame = liftIO do
+  [C.exp| void { ImGui_ImplOpenGL3_NewFrame(); } |]
+
+
+-- | Wraps @ImGui_ImplOpenGL3_RenderDrawData@.
+openGL3RenderDrawData :: MonadIO m => DrawData -> m ()
+openGL3RenderDrawData (DrawData ptr) = liftIO do
+  [C.exp| void { ImGui_ImplOpenGL3_RenderDrawData((ImDrawData*) $( void* ptr )) } |]

src/DearImGui/Raw/Context.hs

@@ -0,0 +1,47 @@
+{-# language DerivingStrategies #-}
+{-# language DuplicateRecordFields #-}
+{-# language GeneralizedNewtypeDeriving #-}
+{-# language NamedFieldPuns #-}
+{-# language OverloadedStrings #-}
+{-# language PatternSynonyms #-}
+{-# language TemplateHaskell #-}
+
+module DearImGui.Raw.Context where
+
+-- containers
+import qualified Data.Map.Strict as Map
+
+-- inline-c
+import Language.C.Inline.Context
+  ( Context(..) )
+import Language.C.Types
+  ( pattern TypeName )
+
+-- dear-imgui
+import DearImGui.Structs
+
+-- dear-imgui-generator
+import DearImGui.Generator
+  ( enumerationsTypesTable )
+
+--------------------------------------------------------------------------------
+
+imguiContext :: Context
+imguiContext = mempty
+  { ctxTypesTable = enumerationsTypesTable <>
+    Map.fromList
+      [ ( TypeName "ImVec2", [t| ImVec2 |] )
+      , ( TypeName "ImVec3", [t| ImVec3 |] )
+      , ( TypeName "ImVec4", [t| ImVec4 |] )
+      , ( TypeName "ImU32", [t| ImU32 |] )
+      , ( TypeName "ImGuiID", [t| ImGuiID |] )
+      , ( TypeName "ImWchar", [t| ImWchar |] )
+      , ( TypeName "ImDrawList", [t| ImDrawList |] )
+      , ( TypeName "ImGuiContext", [t| ImGuiContext |] )
+      , ( TypeName "ImFont", [t| ImFont |] )
+      , ( TypeName "ImFontConfig", [t| ImFontConfig |] )
+      , ( TypeName "ImFontGlyphRangesBuilder", [t| ImFontGlyphRangesBuilder |] )
+      , ( TypeName "ImGuiListClipper", [t| ImGuiListClipper |] )
+      , ( TypeName "ImGuiTableSortSpecs", [t| ImGuiTableSortSpecs |] )
+      ]
+  }

src/DearImGui/Raw/DrawList.hs

@@ -0,0 +1,742 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
+
+{-| Draw command list
+
+This is the low-level list of polygons that ImGui functions are filling.
+
+At the end of the frame, all command lists are passed to your @ImGuiIO::RenderDrawListFn@ function for rendering.
+
+Each dear imgui window contains its own ImDrawList.
+
+You can use 'getWindowDrawList' to access the current window draw list and draw custom primitives.
+
+You can interleave normal ImGui calls and adding primitives to the current draw list.
+
+In single viewport mode, top-left is == @GetMainViewport()->Pos@ (generally @0,0@),
+bottom-right is == @GetMainViewport()->Pos+Size@ (generally io.DisplaySize).
+
+You are totally free to apply whatever transformation matrix to want to the data
+(depending on the use of the transformation you may want to apply it to ClipRect as well!).
+
+__Important__: Primitives are always added to the list and not culled (culling is done at higher-level by ImGui functions),
+if you use this API a lot consider coarse culling your drawn objects.
+-}
+
+module DearImGui.Raw.DrawList
+  ( DrawList(..)
+  , new
+  , destroy
+
+    -- * Primitives
+
+    -- $primitives
+  , addLine
+
+  , addRect
+  , addRectFilled
+  , addRectFilledMultiColor
+
+  , addQuad
+  , addQuadFilled
+
+  , addTriangle
+  , addTriangleFilled
+
+  , addCircle
+  , addCircleFilled
+
+  , addNgon
+  , addNgonFilled
+
+  , addText_
+  , addText
+
+  , addPolyLine
+  , addConvexPolyFilled
+
+  , addBezierCubic
+  , addBezierQuadratic
+
+    -- ** Image primitives
+
+    -- $image
+  , addImage
+  , addImageQuad
+  , addImageRounded
+
+    -- * Stateful path API
+
+    -- $stateful
+  , pathClear
+  , pathLineTo
+  , pathLineToMergeDuplicate
+  , pathFillConvex
+  , pathStroke
+
+  , pathArcTo
+  , pathArcToFast
+
+  , pathBezierCubicCurveTo
+  , pathBezierQuadraticCurveTo
+
+  , pathRect
+
+    -- * Advanced
+
+  -- , addCallback
+  , addDrawCmd
+  , cloneOutput
+
+    -- * Internal state
+
+  , pushClipRect
+  , pushClipRectFullScreen
+  , popClipRect
+  , getClipRectMin
+  , getClipRectMax
+
+  , pushTextureID
+  , popTextureID
+  )
+  where
+
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign hiding (new)
+import Foreign.C
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+import DearImGui.Enums
+import DearImGui.Structs
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+-- | A single draw command list.
+-- Generally one per window, conceptually you may see this as a dynamic "mesh" builder.
+newtype DrawList = DrawList (Ptr ImDrawList)
+
+new :: MonadIO m => m DrawList
+new = liftIO do
+  DrawList <$> [C.block|
+    ImDrawList* {
+      return IM_NEW(ImDrawList(GetDrawListSharedData()));
+    }
+  |]
+
+destroy :: MonadIO m => DrawList -> m ()
+destroy (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      IM_DELETE($(ImDrawList* drawList));
+    }
+  |]
+
+
+pushClipRect :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> CBool -> m ()
+pushClipRect (DrawList drawList) clip_rect_min clip_rect_max intersect_with_current_clip_rect = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PushClipRect(
+        *$(ImVec2* clip_rect_min),
+        *$(ImVec2* clip_rect_max),
+        $(bool intersect_with_current_clip_rect)
+      );
+    }
+  |]
+
+pushClipRectFullScreen :: MonadIO m => DrawList -> m ()
+pushClipRectFullScreen (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PushClipRectFullScreen();
+    }
+  |]
+
+popClipRect :: MonadIO m => DrawList -> m ()
+popClipRect (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PopClipRect();
+    }
+  |]
+
+
+getClipRectMin :: MonadIO m => DrawList -> m ImVec2
+getClipRectMin (DrawList drawList) = liftIO do
+  C.withPtr_ \ptr ->
+    [C.block|
+      void {
+        *$(ImVec2 * ptr) = $(ImDrawList* drawList)->GetClipRectMin();
+      }
+    |]
+
+getClipRectMax :: MonadIO m => DrawList -> m ImVec2
+getClipRectMax (DrawList drawList) = liftIO do
+  C.withPtr_ \ptr ->
+    [C.block|
+      void {
+        *$(ImVec2 * ptr) = $(ImDrawList* drawList)->GetClipRectMax();
+      }
+    |]
+
+
+pushTextureID :: MonadIO m => DrawList -> Ptr () -> m ()
+pushTextureID (DrawList drawList) userTextureIDPtr = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PushTextureID(
+        $(void* userTextureIDPtr)
+      );
+    }
+  |]
+
+popTextureID :: MonadIO m => DrawList -> m ()
+popTextureID (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PopTextureID();
+    }
+  |]
+
+
+{- $primitives
+- For rectangular primitives, @p_min@ and @p_max@ represent the upper-left and lower-right corners.
+- For circle primitives, use @num_segments == 0@ to automatically calculate tessellation (preferred).
+  In older versions (until Dear ImGui 1.77) the 'addCircle' functions defaulted to num_segments == 12.
+  In future versions we will use textures to provide cheaper and higher-quality circles.
+  Use 'addNgon' and 'addNgonFilled' functions if you need to guaranteed a specific number of sides.
+-}
+
+addLine :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> CFloat -> m ()
+addLine (DrawList drawList) p1 p2 col thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddLine(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        $(ImU32 col),
+        $(float thickness)
+      );
+    }
+  |]
+
+
+addRect :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> CFloat -> ImDrawFlags -> CFloat -> m ()
+addRect (DrawList drawList) p_min p_max col rounding flags thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddRect(
+        *$(ImVec2* p_min),
+        *$(ImVec2* p_max),
+        $(ImU32 col),
+        $(float rounding),
+        $(ImDrawFlags flags),
+        $(float thickness)
+      );
+    }
+  |]
+
+addRectFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> CFloat -> ImDrawFlags -> m ()
+addRectFilled (DrawList drawList) p_min p_max col rounding flags = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddRectFilled(
+        *$(ImVec2* p_min),
+        *$(ImVec2* p_max),
+        $(ImU32 col),
+        $(float rounding),
+        $(ImDrawFlags flags)
+      );
+    }
+  |]
+
+addRectFilledMultiColor :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> ImU32 -> ImU32 -> ImU32 -> m ()
+addRectFilledMultiColor (DrawList drawList) p_min p_max col_upr_left col_upr_right col_bot_right col_bot_left = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddRectFilledMultiColor(
+        *$(ImVec2* p_min),
+        *$(ImVec2* p_max),
+        $(ImU32 col_upr_left),
+        $(ImU32 col_upr_right),
+        $(ImU32 col_bot_right),
+        $(ImU32 col_bot_left)
+      );
+    }
+  |]
+
+
+addQuad :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> CFloat -> m ()
+addQuad (DrawList drawList) p1 p2 p3 p4 col thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddQuad(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        *$(ImVec2* p4),
+        $(ImU32 col),
+        $(float thickness)
+      );
+    }
+  |]
+
+addQuadFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> m ()
+addQuadFilled (DrawList drawList) p1 p2 p3 p4 col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddQuadFilled(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        *$(ImVec2* p4),
+        $(ImU32 col)
+      );
+    }
+  |]
+
+
+addTriangle :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> CFloat -> m ()
+addTriangle (DrawList drawList) p1 p2 p3 col thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddTriangle(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        $(ImU32 col),
+        $(float thickness)
+      );
+    }
+  |]
+
+addTriangleFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> ImU32 -> m ()
+addTriangleFilled (DrawList drawList) p1 p2 p3 col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddTriangleFilled(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        $(ImU32 col)
+      );
+    }
+  |]
+
+
+addCircle :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> ImU32 -> CInt -> CFloat -> m ()
+addCircle (DrawList drawList) center radius col num_segments thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddCircle(
+        *$(ImVec2* center),
+        $(float radius),
+        $(ImU32 col),
+        $(int num_segments),
+        $(float thickness)
+      );
+    }
+  |]
+
+addCircleFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> ImU32 -> CInt -> m ()
+addCircleFilled (DrawList drawList) center radius col num_segments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddCircleFilled(
+        *$(ImVec2* center),
+        $(float radius),
+        $(ImU32 col),
+        $(int num_segments)
+      );
+    }
+  |]
+
+
+addNgon :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> ImU32 -> CInt -> CFloat -> m ()
+addNgon (DrawList drawList) center radius col num_segments thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddNgon(
+        *$(ImVec2* center),
+        $(float radius),
+        $(ImU32 col),
+        $(int num_segments),
+        $(float thickness)
+      );
+    }
+  |]
+
+addNgonFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> ImU32 -> CInt -> m ()
+addNgonFilled (DrawList drawList) center radius col num_segments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddNgonFilled(
+        *$(ImVec2* center),
+        $(float radius),
+        $(ImU32 col),
+        $(int num_segments)
+      );
+    }
+  |]
+
+
+addText_ :: MonadIO m => DrawList -> Ptr ImVec2 -> ImU32 -> CString -> CString -> m ()
+addText_ (DrawList drawList) pos col text_begin text_end = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddText(
+        *$(ImVec2* pos),
+        $(ImU32 col),
+        $(char* text_begin),
+        $(char* text_end)
+      );
+    }
+  |]
+
+addText :: MonadIO m => DrawList -> Ptr ImFont -> CFloat -> Ptr ImVec2 -> ImU32 -> CString -> CString -> CFloat -> Ptr ImVec4 -> m ()
+addText (DrawList drawList) fontPtr font_size pos col text_begin text_end wrap_width cpu_fine_clip_rect = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddText(
+        $(ImFont* fontPtr),
+        $(float font_size),
+        *$(ImVec2* pos),
+        $(ImU32 col),
+        $(char* text_begin),
+        $(char* text_end),
+        $(float wrap_width),
+        $(ImVec4* cpu_fine_clip_rect)
+      );
+    }
+  |]
+
+
+addPolyLine :: MonadIO m => DrawList -> Ptr ImVec2 -> CInt -> ImU32 -> ImDrawFlags -> CFloat -> m ()
+addPolyLine (DrawList drawList) points num_points col flags thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddPolyline(
+        $(ImVec2* points),
+        $(int num_points),
+        $(ImU32 col),
+        $(ImDrawFlags flags),
+        $(float thickness)
+      );
+    }
+  |]
+
+addConvexPolyFilled :: MonadIO m => DrawList -> Ptr ImVec2 -> CInt -> ImU32 -> m ()
+addConvexPolyFilled (DrawList drawList) points num_points col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddConvexPolyFilled(
+        $(ImVec2* points),
+        $(int num_points),
+        $(ImU32 col)
+      );
+    }
+  |]
+
+
+addBezierCubic
+  :: MonadIO m
+  => DrawList
+  -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -- Positions (control points)
+  -> ImU32
+  -> CFloat
+  -> CInt
+  -> m ()
+addBezierCubic (DrawList drawList) p1 p2 p3 p4 col thickness numSegments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddBezierCubic(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        *$(ImVec2* p4),
+        $(ImU32 col),
+        $(float thickness),
+        $(int numSegments)
+      );
+    }
+  |]
+
+addBezierQuadratic
+  :: MonadIO m
+  => DrawList
+  -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -- Positions (control points)
+  -> ImU32
+  -> CFloat
+  -> CInt
+  -> m ()
+addBezierQuadratic (DrawList drawList) p1 p2 p3 col thickness numSegments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddBezierQuadratic(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        $(ImU32 col),
+        $(float thickness),
+        $(int numSegments)
+      );
+    }
+  |]
+
+
+{- $image
+* Read FAQ to understand what @ImTextureID@ is.
+* @p_min@ and @p_max@ represent the upper-left and lower-right corners of the rectangle.
+* @uv_min@ and @uv_max@ represent the normalized texture coordinates to use for those corners.
+  Using @(0,0)->(1,1)@ texture coordinates will generally display the entire texture.
+-}
+
+addImage
+  :: MonadIO m
+  => DrawList
+  -> Ptr ()
+  -> Ptr ImVec2 -> Ptr ImVec2 -- Positions
+  -> Ptr ImVec2 -> Ptr ImVec2 -- UVs
+  -> ImU32
+  -> m ()
+addImage (DrawList drawList) userTextureIDPtr p_min p_max uv_min uv_max col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddImage(
+        $(void* userTextureIDPtr),
+        *$(ImVec2* p_min),
+        *$(ImVec2* p_max),
+        *$(ImVec2* uv_min),
+        *$(ImVec2* uv_max),
+        $(ImU32 col)
+      );
+    }
+  |]
+
+addImageQuad
+  :: MonadIO m
+  => DrawList
+  -> Ptr ()
+  -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -- Positions
+  -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -> Ptr ImVec2 -- UVs
+  -> ImU32
+  -> m ()
+addImageQuad (DrawList drawList) userTextureIDPtr p1 p2 p3 p4 uv1 uv2 uv3 uv4 col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddImageQuad(
+        $(void* userTextureIDPtr),
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        *$(ImVec2* p4),
+        *$(ImVec2* uv1),
+        *$(ImVec2* uv2),
+        *$(ImVec2* uv3),
+        *$(ImVec2* uv4),
+        $(ImU32 col)
+      );
+    }
+  |]
+
+addImageRounded
+  :: MonadIO m
+  => DrawList
+  -> Ptr ()
+  -> Ptr ImVec2 -> Ptr ImVec2 -- Positions
+  -> Ptr ImVec2 -> Ptr ImVec2 -- UVs
+  -> ImU32
+  -> CFloat
+  -> ImDrawFlags
+  -> m ()
+addImageRounded (DrawList drawList) userTextureIDPtr p_min p_max uv_min uv_max col rounding flags = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddImageRounded(
+        $(void* userTextureIDPtr),
+        *$(ImVec2* p_min),
+        *$(ImVec2* p_max),
+        *$(ImVec2* uv_min),
+        *$(ImVec2* uv_max),
+        $(ImU32 col),
+        $(float rounding),
+        $(ImDrawFlags flags)
+      );
+    }
+  |]
+
+{- $stateful
+Add points then finish with 'pathFillConvex' or 'pathStroke'.
+-}
+
+pathClear :: MonadIO m => DrawList -> m ()
+pathClear (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathClear();
+    }
+  |]
+
+pathLineTo :: MonadIO m => DrawList -> Ptr ImVec2 -> m ()
+pathLineTo (DrawList drawList) pos = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathLineTo(
+        *$(ImVec2* pos)
+      );
+    }
+  |]
+
+pathLineToMergeDuplicate :: MonadIO m => DrawList -> Ptr ImVec2 -> m ()
+pathLineToMergeDuplicate (DrawList drawList) pos = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathLineToMergeDuplicate(
+        *$(ImVec2* pos)
+      );
+    }
+  |]
+
+-- | Note: Anti-aliased filling requires points to be in clockwise order.
+pathFillConvex :: MonadIO m => DrawList -> ImU32 -> m ()
+pathFillConvex (DrawList drawList) col = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathFillConvex(
+        $(ImU32 col)
+      );
+    }
+  |]
+
+pathStroke :: MonadIO m => DrawList -> ImU32 -> ImDrawFlags -> CFloat -> m ()
+pathStroke (DrawList drawList) col flags thickness = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathStroke(
+        $(ImU32 col),
+        $(ImDrawFlags flags),
+        $(float thickness)
+      );
+    }
+  |]
+
+
+pathArcTo :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> CFloat -> CFloat -> CInt -> m ()
+pathArcTo (DrawList drawList) center radius a_min a_max num_segments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathArcTo(
+        *$(ImVec2* center),
+        $(float radius),
+        $(float a_min),
+        $(float a_max),
+        $(int num_segments)
+      );
+    }
+  |]
+
+-- | Use precomputed angles for a 12 steps circle.
+pathArcToFast :: MonadIO m => DrawList -> Ptr ImVec2 -> CFloat -> CInt -> CInt -> m ()
+pathArcToFast (DrawList drawList) center radius a_min_of_12 a_max_of_12 = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathArcToFast(
+        *$(ImVec2* center),
+        $(float radius),
+        $(int a_min_of_12),
+        $(int a_max_of_12)
+      );
+    }
+  |]
+
+
+pathBezierCubicCurveTo
+  :: MonadIO m
+  => DrawList
+  -> Ptr ImVec2
+  -> Ptr ImVec2
+  -> Ptr ImVec2
+  -> CInt
+  -> m ()
+pathBezierCubicCurveTo (DrawList drawList) p1 p2 p3 num_segments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathBezierCubicCurveTo(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        *$(ImVec2* p3),
+        $(int num_segments)
+      );
+    }
+  |]
+
+pathBezierQuadraticCurveTo
+  :: MonadIO m
+  => DrawList
+  -> Ptr ImVec2
+  -> Ptr ImVec2
+  -> CInt
+  -> m ()
+pathBezierQuadraticCurveTo (DrawList drawList) p1 p2 num_segments = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathBezierQuadraticCurveTo(
+        *$(ImVec2* p1),
+        *$(ImVec2* p2),
+        $(int num_segments)
+      );
+    }
+  |]
+
+
+pathRect :: MonadIO m => DrawList -> Ptr ImVec2 -> Ptr ImVec2 -> CFloat -> ImDrawFlags -> m ()
+pathRect (DrawList drawList) rect_min rect_max rounding flags = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->PathRect(
+        *$(ImVec2* rect_min),
+        *$(ImVec2* rect_max),
+        $(float rounding),
+        $(ImDrawFlags flags)
+      );
+    }
+  |]
+
+
+-- | This is useful if you need to forcefully create a new draw call (to allow for dependent rendering / blending).
+-- Otherwise primitives are merged into the same draw-call as much as possible.
+addDrawCmd :: MonadIO m => DrawList -> m ()
+addDrawCmd (DrawList drawList) = liftIO do
+  [C.block|
+    void {
+      $(ImDrawList* drawList)->AddDrawCmd();
+    }
+  |]
+
+-- | Create a clone of the CmdBuffer/IdxBuffer/VtxBuffer.
+cloneOutput :: MonadIO m => DrawList -> m DrawList
+cloneOutput (DrawList drawList) = liftIO do
+  DrawList <$> [C.block|
+    ImDrawList* {
+      return $(ImDrawList* drawList)->CloneOutput();
+    }
+  |]

src/DearImGui/Raw/Font.hs

@@ -0,0 +1,141 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
+
+
+{-| Fonts
+
+It includes default atlas management, font configuration and glyph ranges.
+
+-}
+
+module DearImGui.Raw.Font
+  ( -- * Types
+    Font(..)
+  , GlyphRanges(..)
+    -- * Adding fonts
+  , addFontDefault
+  , addFontFromFileTTF
+  , addFontFromMemoryTTF
+    -- * Using fonts
+  , pushFont
+  , popFont
+
+    -- * Atlas management
+  , clearFontAtlas
+  , buildFontAtlas
+  )
+  where
+
+-- base
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign ( Ptr, castPtr )
+import Foreign.C
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+import DearImGui.Structs
+import DearImGui.Raw.Font.Config
+  ( FontConfig(..) )
+import DearImGui.Raw.Font.GlyphRanges
+  ( GlyphRanges(..) )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Font runtime data handle
+--
+-- Wraps @ImFont*@.
+newtype Font = Font (Ptr ImFont)
+
+-- | Add the default font (@ProggyClean.ttf@, 13 px) to the atlas.
+addFontDefault :: MonadIO m
+  => m Font   -- ^ Returns font handle for future usage
+addFontDefault = liftIO do
+  Font <$> [C.block|
+    ImFont* {
+      return GetIO().Fonts->AddFontDefault();
+    }
+  |]
+
+-- | Add a custom OTF/TTF font from a file.
+addFontFromFileTTF :: MonadIO m
+  => CString     -- ^ Font file path
+  -> CFloat      -- ^ Font size in pixels
+  -> FontConfig  -- ^ Configuration data
+  -> GlyphRanges -- ^ Glyph ranges to use
+  -> m Font      -- ^ Returns font handle for future usage
+addFontFromFileTTF filenamePtr sizePixels (FontConfig fontConfig) (GlyphRanges glyphRanges) = liftIO do
+  Font <$> [C.block|
+    ImFont* {
+      return GetIO().Fonts->AddFontFromFileTTF(
+        $(char* filenamePtr),
+        $(float sizePixels),
+        $(ImFontConfig* fontConfig),
+        $(ImWchar* glyphRanges));
+    }
+  |]
+
+-- | Transfer a buffer with TTF data to font atlas builder.
+addFontFromMemoryTTF :: MonadIO m => CStringLen -> CFloat -> FontConfig -> GlyphRanges -> m Font
+addFontFromMemoryTTF (castPtr -> fontDataPtr, fromIntegral -> fontSize) sizePixels (FontConfig fontConfig) (GlyphRanges glyphRanges) = liftIO do
+  Font <$> [C.block|
+    ImFont* {
+      return GetIO().Fonts->AddFontFromMemoryTTF(
+        $(void* fontDataPtr),
+        $(int fontSize),
+        $(float sizePixels),
+        $(ImFontConfig* fontConfig),
+        $(ImWchar* glyphRanges)
+      );
+    }
+  |]
+
+
+-- | Pushes a font into the parameters stack,
+-- so ImGui would render following text using it.
+pushFont :: MonadIO m => Font -> m ()
+pushFont (Font font) = liftIO do
+  [C.exp| void { PushFont($(ImFont* font)); } |]
+
+-- | Pops a font pushed into the parameters stack
+--
+-- Should be called only after a corresponding 'pushFont' call.
+popFont :: MonadIO m => m ()
+popFont = liftIO do
+  [C.exp| void { PopFont(); } |]
+
+-- | Explicitly build pixels data for the atlas.
+buildFontAtlas :: MonadIO m => m ()
+buildFontAtlas = liftIO do
+  [C.block|
+    void {
+      GetIO().Fonts->Build();
+    }
+  |]
+
+-- | Clear all font atlas input and output data
+clearFontAtlas :: MonadIO m => m ()
+clearFontAtlas = liftIO do
+  [C.block|
+    void {
+      GetIO().Fonts->Clear();
+    }
+  |]

src/DearImGui/Raw/Font/Config.hs

@@ -0,0 +1,256 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
+
+
+{-| Font configuration
+
+IO functions to modify font config values.
+
+-}
+
+module DearImGui.Raw.Font.Config
+  ( FontConfig(..)
+  , new
+  , destroy
+    -- * Changing settings
+  , setFontDataOwnedByAtlas
+  , setFontNo
+  , setSizePixels
+  , setOversampleH
+  , setOversampleV
+  , setPixelSnapH
+  , setGlyphExtraSpacing
+  , setGlyphOffset
+  , setGlyphRanges
+  , setGlyphMinAdvanceX
+  , setGlyphMaxAdvanceX
+  , setMergeMode
+  , setFontBuilderFlags
+  , setRasterizerMultiply
+  , setEllipsisChar
+  )
+  where
+
+-- base
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign ( Ptr )
+import Foreign.C
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+import DearImGui.Structs
+import DearImGui.Raw.Font.GlyphRanges
+  ( GlyphRanges(..) )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+-- | Font configuration data handle
+--
+-- Wraps @ImFontConfig*@.
+newtype FontConfig = FontConfig (Ptr ImFontConfig)
+
+-- | Create an instance of config
+new :: MonadIO m => m FontConfig
+new = liftIO do
+  FontConfig <$> [C.block|
+    ImFontConfig* {
+      return IM_NEW(ImFontConfig);
+    }
+  |]
+
+-- | Destroy an instance of config
+--
+-- Should be used __after__ font atlas building.
+destroy :: MonadIO m => FontConfig -> m ()
+destroy (FontConfig config) = liftIO do
+  [C.block|
+    void {
+      IM_DELETE($(ImFontConfig* config));
+    }
+  |]
+
+
+-- | TTF/OTF data ownership taken by the container ImFontAtlas (will delete memory itself).
+--
+-- By default, it is @true@
+setFontDataOwnedByAtlas :: MonadIO m => FontConfig -> CBool -> m ()
+setFontDataOwnedByAtlas (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->FontDataOwnedByAtlas = $(bool value);
+    }
+  |]
+
+-- | Index of font within TTF/OTF file
+--
+-- By default, it is @0@
+setFontNo :: MonadIO m => FontConfig -> CInt -> m ()
+setFontNo (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->FontNo = $(int value);
+    }
+  |]
+
+-- | Size in pixels for rasterizer (more or less maps to the resulting font height).
+--
+-- Implicitly set by @addFont...@ functions.
+setSizePixels :: MonadIO m => FontConfig -> CFloat -> m ()
+setSizePixels (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->SizePixels = $(float value);
+    }
+  |]
+
+-- | Rasterize at higher quality for sub-pixel positioning. Note the difference between 2 and 3 is minimal so you can reduce this to 2 to save memory. Read https://github.com/nothings/stb/blob/master/tests/oversample/README.md for details.
+--
+-- By default, it is @3@
+setOversampleH :: MonadIO m => FontConfig -> CInt -> m ()
+setOversampleH (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->OversampleH = $(int value);
+    }
+  |]
+
+-- | Rasterize at higher quality for sub-pixel positioning. This is not really useful as we don't use sub-pixel positions on the Y axis.
+--
+-- By default, it is @1@
+setOversampleV :: MonadIO m => FontConfig -> CInt -> m ()
+setOversampleV (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->OversampleV = $(int value);
+    }
+  |]
+
+-- | Align every glyph to pixel boundary. Useful e.g. if you are merging a non-pixel aligned font with the default font. If enabled, you can set OversampleH/V to 1.
+--
+-- By default, it is @false@
+setPixelSnapH :: MonadIO m => FontConfig -> CBool -> m ()
+setPixelSnapH (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->PixelSnapH = $(bool value);
+    }
+  |]
+
+-- | Extra spacing (in pixels) between glyphs. Only X axis is supported for now.
+--
+-- By default, it is @0, 0@
+setGlyphExtraSpacing :: MonadIO m => FontConfig -> Ptr ImVec2 -> m ()
+setGlyphExtraSpacing (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->GlyphExtraSpacing = *$(ImVec2* value);
+    }
+  |]
+
+-- | Offset all glyphs from this font input.
+--
+-- By default, it is @0, 0@
+setGlyphOffset :: MonadIO m => FontConfig -> Ptr ImVec2 -> m ()
+setGlyphOffset (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->GlyphOffset = *$(ImVec2* value);
+    }
+  |]
+
+-- | Pointer to a user-provided list of Unicode range (2 value per range, values are inclusive, zero-terminated list). THE ARRAY DATA NEEDS TO PERSIST AS LONG AS THE FONT IS ALIVE.
+--
+-- By default, it is @NULL@
+setGlyphRanges :: MonadIO m => FontConfig -> GlyphRanges -> m ()
+setGlyphRanges (FontConfig fc) (GlyphRanges value) = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->GlyphRanges = $(ImWchar* value);
+    }
+  |]
+
+-- | Minimum AdvanceX for glyphs, set Min to align font icons, set both Min/Max to enforce mono-space font
+--
+-- By default, it is @0@
+setGlyphMinAdvanceX :: MonadIO m => FontConfig -> CFloat -> m ()
+setGlyphMinAdvanceX (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->GlyphMinAdvanceX = $(float value);
+    }
+  |]
+
+-- | Maximum AdvanceX for glyphs
+--
+-- By default, it is @FLT_MAX@
+setGlyphMaxAdvanceX :: MonadIO m => FontConfig -> CFloat -> m ()
+setGlyphMaxAdvanceX (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->GlyphMaxAdvanceX = $(float value);
+    }
+  |]
+
+-- | Merge into previous ImFont, so you can combine multiple inputs font into one ImFont (e.g. ASCII font + icons + Japanese glyphs). You may want to use GlyphOffset.y when merge font of different heights.
+--
+-- By default, it is @false@
+setMergeMode :: MonadIO m => FontConfig -> CBool -> m ()
+setMergeMode (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->MergeMode = $(bool value);
+    }
+  |]
+
+-- | Settings for custom font builder.
+-- THIS IS BUILDER IMPLEMENTATION DEPENDENT.
+--
+-- By default, it is @0@. Leave it so if unsure.
+setFontBuilderFlags :: MonadIO m => FontConfig -> CUInt -> m ()
+setFontBuilderFlags (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->FontBuilderFlags = $(unsigned int value);
+    }
+  |]
+
+-- | Brighten (>1.0f) or darken (<1.0f) font output.
+-- Brightening small fonts may be a good workaround to make them more readable.
+--
+-- By default, it is @1.0f@
+setRasterizerMultiply :: MonadIO m => FontConfig -> CFloat -> m ()
+setRasterizerMultiply (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->RasterizerMultiply = $(float value);
+    }
+  |]
+
+-- | Explicitly specify unicode codepoint of ellipsis character. When fonts are being merged first specified ellipsis will be used.
+--
+-- By default, it is @-1@
+setEllipsisChar :: MonadIO m => FontConfig -> ImWchar -> m ()
+setEllipsisChar (FontConfig fc) value = liftIO do
+  [C.block|
+    void {
+      $(ImFontConfig* fc)->EllipsisChar = $(ImWchar value);
+    }
+  |]

src/DearImGui/Raw/Font/GlyphRanges.hs

@@ -0,0 +1,295 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-| Font glyph ranges builder
+
+Helper to build glyph ranges from text/string data.
+Feed your application strings/characters to it then call 'buildRanges'.
+
+Low-level example of usage:
+
+@
+  -- import ImGui.Fonts
+  -- import ImGui.Raw.GlyphRangesBuilder as GRB
+
+  builder <- GRB.new
+
+  GRB.addRanges builder getGlyphRangesDefault
+  liftIO $ withCString "Привет" $ GRB.addText builder
+  rangesVec <- GRB.buildRanges builder
+  let ranges = GRB.fromRangesVector rangesVec
+
+  addFontFromFileTTF'
+    "./imgui/misc/fonts/DroidSans.ttf" 12
+    Nothing
+    (Just ranges)
+
+  -- it is strictly necessary to explicitly build the atlas
+  buildFontAtlas
+
+  -- resource destruction comes only after the building
+  GRB.destroyRangesVector rangesVec
+  GRB.destroy builder
+@
+
+-}
+
+module DearImGui.Raw.Font.GlyphRanges
+  ( GlyphRanges(..)
+
+    -- * Built-in ranges
+  , Builtin(..)
+  , getBuiltin
+  , builtinSetup
+
+    -- * Preparing a builder
+  , GlyphRangesBuilder(..)
+  , new
+  , destroy
+  , addChar
+  , addText
+  , addRanges
+
+    -- * Extracting data
+  , GlyphRangesVector(..)
+  , buildRangesVector
+  , fromRangesVector
+  , destroyRangesVector
+  )
+  where
+
+-- base
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign ( Ptr )
+import Foreign.C
+import System.IO.Unsafe (unsafePerformIO)
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+import DearImGui.Structs
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+-- | Glyph ranges handle
+--
+-- Wraps @ImWchar*@.
+newtype GlyphRanges = GlyphRanges (Ptr ImWchar)
+
+-- | Builtin glyph ranges tags.
+data Builtin
+  = Latin
+  | Korean
+  | Japanese
+  | ChineseFull
+  | ChineseSimplifiedCommon
+  | Cyrillic
+  | Thai
+  | Vietnamese
+  deriving (Eq, Ord, Show, Enum, Bounded)
+
+-- | Get builtin glyph ranges from a tag.
+getBuiltin :: Builtin -> GlyphRanges
+getBuiltin = \case
+  Latin                   -> getGlyphRangesDefault
+  Korean                  -> getGlyphRangesKorean
+  Japanese                -> getGlyphRangesJapanese
+  ChineseFull             -> getGlyphRangesChineseFull
+  ChineseSimplifiedCommon -> getGlyphRangesChineseSimplifiedCommon
+  Cyrillic                -> getGlyphRangesCyrillic
+  Thai                    -> getGlyphRangesThai
+  Vietnamese              -> getGlyphRangesVietnamese
+
+-- | Special case of @getBuiltin@, but for font source setup.
+builtinSetup :: Builtin -> Maybe GlyphRanges
+builtinSetup = \case
+  Latin -> Nothing
+  others  -> Just (getBuiltin others)
+
+-- | Basic Latin, Extended Latin
+getGlyphRangesDefault :: GlyphRanges
+getGlyphRangesDefault = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesDefault();
+    }
+  |]
+
+-- | Default + Korean characters
+getGlyphRangesKorean :: GlyphRanges
+getGlyphRangesKorean = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesKorean();
+    }
+  |]
+
+-- | Default + Hiragana, Katakana, Half-Width, Selection of 2999 Ideographs
+getGlyphRangesJapanese :: GlyphRanges
+getGlyphRangesJapanese = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesJapanese();
+    }
+  |]
+
+-- | Default + Half-Width + Japanese Hiragana/Katakana + full set of about 21000 CJK Unified Ideographs
+getGlyphRangesChineseFull :: GlyphRanges
+getGlyphRangesChineseFull = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesChineseFull();
+    }
+  |]
+
+-- | Default + Half-Width + Japanese Hiragana/Katakana + set of 2500 CJK Unified Ideographs for common simplified Chinese
+getGlyphRangesChineseSimplifiedCommon :: GlyphRanges
+getGlyphRangesChineseSimplifiedCommon = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesChineseSimplifiedCommon();
+    }
+  |]
+
+-- | Default + about 400 Cyrillic characters
+getGlyphRangesCyrillic :: GlyphRanges
+getGlyphRangesCyrillic = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesCyrillic();
+    }
+  |]
+
+-- | Default + Thai characters
+getGlyphRangesThai :: GlyphRanges
+getGlyphRangesThai = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesThai();
+    }
+  |]
+
+-- | Default + Vietnamese characters
+getGlyphRangesVietnamese :: GlyphRanges
+getGlyphRangesVietnamese = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    const ImWchar* {
+      return GetIO().Fonts->GetGlyphRangesVietnamese();
+    }
+  |]
+
+-- | Glyph ranges builder handle
+--
+-- Wraps @ImFontGlyphRangesBuilder*@.
+newtype GlyphRangesBuilder = GlyphRangesBuilder (Ptr ImFontGlyphRangesBuilder)
+
+-- | Glyph ranges vector handle to keep builder output
+--
+-- Wraps @ImVector<ImWchar>*@.
+newtype GlyphRangesVector = GlyphRangesVector (Ptr ())
+
+
+-- | Create an instance of builder
+new :: MonadIO m => m GlyphRangesBuilder
+new = liftIO do
+  GlyphRangesBuilder <$> [C.block|
+    ImFontGlyphRangesBuilder* {
+      return IM_NEW(ImFontGlyphRangesBuilder);
+    }
+  |]
+
+-- | Destroy an instance of builder
+--
+-- Should be used __after__ font atlas building.
+destroy :: MonadIO m => GlyphRangesBuilder -> m ()
+destroy (GlyphRangesBuilder builder) = liftIO do
+  [C.block|
+    void {
+      IM_DELETE($(ImFontGlyphRangesBuilder* builder));
+    }
+  |]
+
+
+-- | Add character
+addChar :: MonadIO m => GlyphRangesBuilder -> ImWchar -> m ()
+addChar (GlyphRangesBuilder builder) wChar = liftIO do
+  [C.block|
+    void {
+      $(ImFontGlyphRangesBuilder* builder)->AddChar($(ImWchar wChar));
+    }
+  |]
+
+-- | Add string (each character of the UTF-8 string are added)
+addText :: MonadIO m => GlyphRangesBuilder -> CString -> m ()
+addText (GlyphRangesBuilder builder) string = liftIO do
+  [C.block|
+    void {
+      $(ImFontGlyphRangesBuilder* builder)->AddText($(char* string));
+    }
+  |]
+-- FIXME: the function uses 'const char* text_end = NULL' parameter,
+--   which is pointer for the line ending. It is low level, though it
+--   could be utilized for string length parameter.
+
+-- | Add ranges, e.g. 'addRanges builder getGlyphRangesDefault'
+-- to force add all of ASCII/Latin+Ext
+addRanges :: MonadIO m => GlyphRangesBuilder -> GlyphRanges -> m()
+addRanges (GlyphRangesBuilder builder) (GlyphRanges ranges) = liftIO do
+  [C.block|
+    void {
+      $(ImFontGlyphRangesBuilder* builder)->AddRanges($(ImWchar* ranges));
+    }
+  |]
+
+
+-- | Build new ranges and create ranges vector instance,
+-- containing them
+buildRangesVector :: MonadIO m => GlyphRangesBuilder -> m (GlyphRangesVector)
+buildRangesVector (GlyphRangesBuilder builder) = liftIO do
+  GlyphRangesVector <$> [C.block|
+    void* {
+      ImVector<ImWchar>* ranges = IM_NEW(ImVector<ImWchar>);
+      $(ImFontGlyphRangesBuilder* builder)->BuildRanges(ranges);
+      return ranges;
+    }
+  |]
+
+-- | Extract glyph ranges from a vector
+--
+-- Should be used __before__ vector destruction.
+fromRangesVector :: GlyphRangesVector -> GlyphRanges
+fromRangesVector (GlyphRangesVector vecPtr) = unsafePerformIO do
+  GlyphRanges <$> [C.block|
+    ImWchar* {
+      return ((ImVector<ImWchar>*) $(void* vecPtr))->Data;
+    }
+  |]
+
+-- | Destroy a ranges vector instance
+--
+-- Should be used __after__ font atlas building.
+destroyRangesVector :: MonadIO m => GlyphRangesVector -> m ()
+destroyRangesVector (GlyphRangesVector vecPtr) = liftIO do
+  [C.block|
+    void {
+      IM_DELETE(((ImVector<ImWchar>*) $(void* vecPtr)));
+    }
+  |]

src/DearImGui/Raw/IO.hs

@@ -0,0 +1,134 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
+
+{-| Main configuration and I/O between your application and ImGui
+
+-}
+
+module DearImGui.Raw.IO
+  ( setIniFilename
+  , setLogFilename
+
+  , setMouseDoubleClickMaxDist
+  , setMouseDoubleClickTime
+  , setMouseDragThreshold
+
+  , setKeyRepeatDelay
+  , setKeyRepeatRate
+
+  , setUserData
+  ) where
+
+-- TODO: add exports
+
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign
+  ( Ptr )
+import Foreign.C
+  ( CFloat(..)
+  , CString
+  )
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+-- import DearImGui.Enums
+-- import DearImGui.Structs
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+setIniFilename :: MonadIO m => CString -> m ()
+setIniFilename ptr = liftIO do
+  [C.block|
+    void {
+      GetIO().IniFilename = $(char * ptr);
+    }
+  |]
+
+setLogFilename :: MonadIO m => CString -> m ()
+setLogFilename ptr = liftIO do
+  [C.block|
+    void {
+      GetIO().LogFilename = $(char * ptr);
+    }
+  |]
+
+setMouseDoubleClickTime :: MonadIO m => CFloat -> m ()
+setMouseDoubleClickTime seconds = liftIO do
+  [C.block|
+    void {
+      GetIO().MouseDoubleClickTime = $(float seconds);
+    }
+  |]
+
+setMouseDoubleClickMaxDist :: MonadIO m => CFloat -> m ()
+setMouseDoubleClickMaxDist pixels = liftIO do
+  [C.block|
+    void {
+      GetIO().MouseDoubleClickMaxDist = $(float pixels);
+    }
+  |]
+
+setMouseDragThreshold :: MonadIO m => CFloat -> m ()
+setMouseDragThreshold pixels = liftIO do
+  [C.block|
+    void {
+      GetIO().MouseDragThreshold = $(float pixels);
+    }
+  |]
+
+setKeyRepeatDelay :: MonadIO m => CFloat -> m ()
+setKeyRepeatDelay seconds = liftIO do
+  [C.block|
+    void {
+      GetIO().KeyRepeatDelay = $(float seconds);
+    }
+  |]
+
+setKeyRepeatRate :: MonadIO m => CFloat -> m ()
+setKeyRepeatRate pixels = liftIO do
+  [C.block|
+    void {
+      GetIO().KeyRepeatRate = $(float pixels);
+    }
+  |]
+
+setUserData :: MonadIO m => Ptr () -> m ()
+setUserData ptr = liftIO do
+  [C.block|
+    void {
+      GetIO().UserData = $(void* ptr);
+    }
+  |]
+
+{- TODO:
+
+bool   WantTextInput;            // Mobile/console: when set, you may display an on-screen keyboard. This is set by Dear ImGui when it wants textual keyboard input to happen (e.g. when a InputText widget is active).
+bool   WantSetMousePos;          // MousePos has been altered, backend should reposition mouse on next frame. Rarely used! Set only when ImGuiConfigFlags_NavEnableSetMousePos flag is enabled.
+bool   WantSaveIniSettings;      // When manual .ini load/save is active (io.IniFilename == NULL), this will be set to notify your application that you can call SaveIniSettingsToMemory() and save yourself. Important: clear io.WantSaveIniSettings yourself after saving!
+bool   NavActive;                // Keyboard/Gamepad navigation is currently allowed (will handle ImGuiKey_NavXXX events) = a window is focused and it doesn't use the ImGuiWindowFlags_NoNavInputs flag.
+bool   NavVisible;               // Keyboard/Gamepad navigation is visible and allowed (will handle ImGuiKey_NavXXX events).
+int    MetricsRenderVertices;    // Vertices output during last call to Render()
+int    MetricsRenderIndices;     // Indices output during last call to Render() = number of triangles * 3
+int    MetricsRenderWindows;     // Number of visible windows
+int    MetricsActiveWindows;     // Number of active windows
+int    MetricsActiveAllocations; // Number of active allocations, updated by MemAlloc/MemFree based on current context. May be off if you have multiple imgui contexts.
+ImVec2 MouseDelta;
+-}

src/DearImGui/Raw/ListClipper.hs

@@ -0,0 +1,149 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
+
+{-| Helper: Manually clip large list of items.
+
+If you are submitting lots of evenly spaced items and you have a random access to the list,
+you can perform coarse clipping based on visibility to save yourself from processing those items at all.
+
+The clipper calculates the range of visible items and advance the cursor to compensate for the non-visible items we have skipped.
+
+Dear ImGui already clips items based on their bounds but it needs to measure text size to do so,
+whereas manual coarse clipping before submission makes this cost and your own data fetching/submission cost almost null.
+
+Usage:
+
+@
+clipper <- ListClipper.new
+ListClipper.begin clipper 1000 -- We have 1000 elements, evenly spaced.
+whileTrue (ListClipper.step clipper) $
+  start <- ListClipper.displayStart clipper
+  end <- ListClipper.displayEnd clipper
+  for_ [start .. end] \ix ->
+    ImGui.text $ "line number " <> show ix
+@
+
+Generally what happens is:
+
+* Clipper lets you process the first element (DisplayStart = 0, DisplayEnd = 1) regardless of it being visible or not.
+* User code submit one element.
+* Clipper can measure the height of the first element
+* Clipper calculate the actual range of elements to display based on the current clipping rectangle,
+  position the cursor before the first visible element.
+* User code submit visible elements.
+-}
+
+module DearImGui.Raw.ListClipper
+  ( ListClipper
+  , new
+  , delete
+  , begin
+  , displayStart
+  , displayEnd
+  , step
+  )
+  where
+
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign hiding (new)
+import Foreign.C
+import System.IO.Unsafe (unsafePerformIO)
+
+-- dear-imgui
+import DearImGui.Raw.Context
+  ( imguiContext )
+import DearImGui.Structs
+  ( ImGuiListClipper )
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+
+-- | @ImGuiListClipper@ object handle.
+type ListClipper = Ptr ImGuiListClipper
+
+
+-- | Create a new 'ListClipper' instance.
+new :: (MonadIO m) => m ListClipper
+new = liftIO do
+  [C.block|
+    ImGuiListClipper* {
+      return IM_NEW(ImGuiListClipper);
+    }
+  |]
+
+-- | Destroy 'ListClipper' instance.
+delete :: (MonadIO m) => ListClipper -> m ()
+delete clipper = liftIO do
+  [C.block|
+    void {
+      IM_DELETE($(ImGuiListClipper* clipper));
+    }
+  |]
+
+
+-- | ListClipper setup
+--
+-- @items_count@: Use 'maxBound' if you don't know how many items you have
+-- (in which case the cursor won't be advanced in the final step).
+--
+-- @items_height@: Use -1.0f to be calculated automatically on first step.
+-- Otherwise pass in the distance between your items, typically
+-- 'getTextLineHeightWithSpacing' or 'getFrameHeightWithSpacing'.
+--
+-- Wraps @ListClipper::Begin()@.
+begin :: (MonadIO m) => ListClipper -> CInt -> CFloat -> m ()
+begin clipper items_count items_height = liftIO do
+  [C.block|
+    void {
+      $(ImGuiListClipper* clipper)->Begin($(int items_count), $(float items_height));
+    }
+  |]
+
+-- | An accessor for @ListClipper::Begin@
+displayStart :: ListClipper -> CInt
+displayStart clipper = unsafePerformIO do
+  [C.exp|
+    int {
+      $(ImGuiListClipper* clipper)->DisplayStart
+    }
+  |]
+
+-- | An accessor for @ListClipper::DisplayStart@
+displayEnd :: ListClipper -> CInt
+displayEnd clipper = unsafePerformIO
+  [C.exp|
+    int {
+      $(ImGuiListClipper* clipper)->DisplayEnd
+    }
+  |]
+
+
+-- | Call until it returns 'False'.
+--
+-- The 'displayStart'/'displayEnd' fields will be set and you can process/draw those items.
+--
+-- Wraps @ListClipper::Step()@.
+step :: (MonadIO m) => ListClipper -> m Bool
+step clipper = liftIO do
+  (0 /=) <$> [C.block|
+    bool {
+      return $(ImGuiListClipper* clipper)->Step();
+    }
+  |]

src/DearImGui/SDL.hs

@@ -21,12 +21,14 @@ module DearImGui.SDL (
   , sdl2Shutdown
   , pollEventWithImGui
   , pollEventsWithImGui
+    -- *** Raw
+  , dispatchRawEvent
   )
   where
 
 -- base
 import Control.Monad
-  ( when )
+  ( void, when )
 import Foreign.Marshal.Alloc
   ( alloca )
 import Foreign.Ptr
@@ -40,9 +42,9 @@ import qualified Language.C.Inline.Cpp as Cpp
 
 -- sdl2
 import SDL
-import SDL.Internal.Types
 import SDL.Raw.Enum as Raw
 import qualified SDL.Raw.Event as Raw
+import qualified SDL.Raw.Types as Raw
 
 -- transformers
 import Control.Monad.IO.Class
@@ -51,15 +53,15 @@ import Control.Monad.IO.Class
 
 C.context (Cpp.cppCtx <> C.bsCtx)
 C.include "imgui.h"
-C.include "backends/imgui_impl_sdl.h"
+C.include "backends/imgui_impl_sdl2.h"
 C.include "SDL.h"
 Cpp.using "namespace ImGui"
 
 
 -- | Wraps @ImGui_ImplSDL2_NewFrame@.
-sdl2NewFrame :: MonadIO m => Window -> m ()
-sdl2NewFrame (Window windowPtr) = liftIO do
-  [C.exp| void { ImGui_ImplSDL2_NewFrame((SDL_Window*)($(void* windowPtr))); } |]
+sdl2NewFrame :: MonadIO m => m ()
+sdl2NewFrame = liftIO do
+  [C.exp| void { ImGui_ImplSDL2_NewFrame(); } |]
 
 
 -- | Wraps @ImGui_ImplSDL2_Shutdown@.
@@ -78,11 +80,24 @@ pollEventWithImGui = liftIO do
     nEvents <- Raw.peepEvents evPtr 1 Raw.SDL_PEEKEVENT Raw.SDL_FIRSTEVENT Raw.SDL_LASTEVENT
 
     when (nEvents > 0) do
-      let evPtr' = castPtr evPtr :: Ptr ()
-      [C.exp| void { ImGui_ImplSDL2_ProcessEvent((SDL_Event*) $(void* evPtr')) } |]
+      void $ dispatchRawEvent evPtr
 
     pollEvent
 
+-- | Dispatch a raw 'Raw.Event' value to Dear ImGui.
+--
+-- You may want this function instead of 'pollEventWithImGui' if you do not use
+-- @sdl2@'s higher-level 'Event' type (e.g. your application has its own polling
+-- mechanism).
+--
+-- __It is your application's responsibility to both manage the input__
+-- __pointer's memory and to fill the memory location with a raw 'Raw.Event'__
+-- __value.__
+dispatchRawEvent :: MonadIO m => Ptr Raw.Event -> m Bool
+dispatchRawEvent evPtr = liftIO do
+  let evPtr' = castPtr evPtr :: Ptr ()
+  (0 /=) <$> [C.exp| bool { ImGui_ImplSDL2_ProcessEvent((const SDL_Event*) $(void* evPtr')) } |]
+
 -- | Like the SDL2 'pollEvents' function, while also dispatching the events to
 -- Dear ImGui. See 'pollEventWithImGui'.
 pollEventsWithImGui :: MonadIO m => m [Event]

src/DearImGui/SDL/OpenGL.hs

@@ -42,7 +42,7 @@ import Control.Monad.IO.Class
 C.context (Cpp.cppCtx <> C.bsCtx)
 C.include "imgui.h"
 C.include "backends/imgui_impl_opengl2.h"
-C.include "backends/imgui_impl_sdl.h"
+C.include "backends/imgui_impl_sdl2.h"
 C.include "SDL.h"
 C.include "SDL_opengl.h"
 Cpp.using "namespace ImGui"

src/DearImGui/SDL/Renderer.hs

@@ -0,0 +1,74 @@
+{-# LANGUAGE BlockArguments #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE TemplateHaskell #-}
+
+{-|
+Module: DearImGUI.SDL.Renderer
+
+Initialising the SDL2 renderer backend for Dear ImGui.
+-}
+
+module DearImGui.SDL.Renderer
+  ( sdl2InitForSDLRenderer
+  , sdlRendererInit
+  , sdlRendererShutdown
+  , sdlRendererNewFrame
+  , sdlRendererRenderDrawData
+  )
+  where
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+-- sdl2
+import SDL.Internal.Types
+  ( Renderer(..), Window(..) )
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+
+-- DearImGui
+import DearImGui
+  ( DrawData(..) )
+
+
+C.context (Cpp.cppCtx <> C.bsCtx)
+C.include "imgui.h"
+C.include "backends/imgui_impl_sdlrenderer2.h"
+C.include "backends/imgui_impl_sdl2.h"
+C.include "SDL.h"
+Cpp.using "namespace ImGui"
+
+
+-- | Wraps @ImGui_ImplSDL2_InitForSDLRenderer@.
+sdl2InitForSDLRenderer :: MonadIO m => Window -> Renderer -> m Bool
+sdl2InitForSDLRenderer (Window windowPtr) (Renderer renderPtr) = liftIO do
+  (0 /=) <$> [C.exp| bool { ImGui_ImplSDL2_InitForSDLRenderer((SDL_Window*)$(void* windowPtr), (SDL_Renderer*)$(void* renderPtr)) } |]
+
+-- | Wraps @ImGui_ImplSDLRenderer2_Init@.
+sdlRendererInit :: MonadIO m => Renderer -> m Bool
+sdlRendererInit (Renderer renderPtr) = liftIO do
+  (0 /=) <$> [C.exp| bool { ImGui_ImplSDLRenderer2_Init((SDL_Renderer*)$(void* renderPtr)) } |]
+
+-- | Wraps @ImGui_ImplSDLRenderer2_Shutdown@.
+sdlRendererShutdown :: MonadIO m => m ()
+sdlRendererShutdown = liftIO do
+  [C.exp| void { ImGui_ImplSDLRenderer2_Shutdown(); } |]
+
+-- | Wraps @ImGui_ImplSDLRenderer2_NewFrame@.
+sdlRendererNewFrame :: MonadIO m => m ()
+sdlRendererNewFrame = liftIO do
+  [C.exp| void { ImGui_ImplSDLRenderer2_NewFrame(); } |]
+
+-- | Wraps @ImGui_ImplSDLRenderer2_RenderDrawData@.
+sdlRendererRenderDrawData :: MonadIO m => DrawData -> m ()
+sdlRendererRenderDrawData (DrawData ptr) = liftIO do
+  [C.exp| void { ImGui_ImplSDLRenderer2_RenderDrawData((ImDrawData*) $( void* ptr )) } |]

src/DearImGui/SDL/Vulkan.hs

@@ -33,7 +33,7 @@ import Control.Monad.IO.Class ( MonadIO, liftIO )
 C.context Cpp.cppCtx
 C.include "imgui.h"
 C.include "backends/imgui_impl_vulkan.h"
-C.include "backends/imgui_impl_sdl.h"
+C.include "backends/imgui_impl_sdl2.h"
 C.include "SDL.h"
 C.include "SDL_vulkan.h"
 Cpp.using "namespace ImGui"

src/DearImGui/Structs.hs

@@ -0,0 +1,214 @@
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE CPP #-}
+
+module DearImGui.Structs where
+
+-- base
+import Data.Word
+  ( Word32
+#ifndef IMGUI_USE_WCHAR32
+  , Word16
+#endif
+  )
+
+import Foreign
+  ( Storable(..), castPtr, plusPtr, Ptr, Int16, nullPtr )
+import Foreign.C
+  ( CInt, CBool )
+
+import DearImGui.Enums
+import Data.Bits ((.&.))
+
+--------------------------------------------------------------------------------
+data ImVec2 = ImVec2 { x, y :: {-# unpack #-} !Float }
+  deriving (Show)
+
+
+instance Storable ImVec2 where
+  sizeOf ~ImVec2{x, y} = sizeOf x + sizeOf y
+
+  alignment _ = 0
+
+  poke ptr ImVec2{ x, y } = do
+    poke (castPtr ptr `plusPtr` (sizeOf x * 0)) x
+    poke (castPtr ptr `plusPtr` (sizeOf x * 1)) y
+
+  peek ptr = do
+    x <- peek (castPtr ptr                         )
+    y <- peek (castPtr ptr `plusPtr` (sizeOf x * 1))
+    return ImVec2{ x, y  }
+
+
+data ImVec3 = ImVec3 { x, y, z :: {-# unpack #-} !Float }
+  deriving (Show)
+
+
+instance Storable ImVec3 where
+  sizeOf ~ImVec3{x, y, z} = sizeOf x + sizeOf y + sizeOf z
+
+  alignment _ = 0
+
+  poke ptr ImVec3{ x, y, z } = do
+    poke (castPtr ptr `plusPtr` (sizeOf x * 0)) x
+    poke (castPtr ptr `plusPtr` (sizeOf x * 1)) y
+    poke (castPtr ptr `plusPtr` (sizeOf x * 2)) z
+
+  peek ptr = do
+    x <- peek (castPtr ptr                         )
+    y <- peek (castPtr ptr `plusPtr` (sizeOf x * 1))
+    z <- peek (castPtr ptr `plusPtr` (sizeOf x * 2))
+    return ImVec3{ x, y, z }
+
+
+data ImVec4 = ImVec4 { x, y, z, w :: {-# unpack #-} !Float }
+  deriving (Show)
+
+
+instance Storable ImVec4 where
+  sizeOf ~ImVec4{x, y, z, w} = sizeOf x + sizeOf y + sizeOf z + sizeOf w
+
+  alignment _ = 0
+
+  poke ptr ImVec4{ x, y, z, w } = do
+    poke (castPtr ptr `plusPtr` (sizeOf x * 0)) x
+    poke (castPtr ptr `plusPtr` (sizeOf x * 1)) y
+    poke (castPtr ptr `plusPtr` (sizeOf x * 2)) z
+    poke (castPtr ptr `plusPtr` (sizeOf x * 3)) w
+
+  peek ptr = do
+    x <- peek (castPtr ptr                         )
+    y <- peek (castPtr ptr `plusPtr` (sizeOf x * 1))
+    z <- peek (castPtr ptr `plusPtr` (sizeOf x * 2))
+    w <- peek (castPtr ptr `plusPtr` (sizeOf x * 3))
+    return ImVec4{ x, y, z, w }
+
+--------------------------------------------------------------------------------
+
+-- | DearImGui context handle.
+data ImGuiContext
+
+-- | Individual font handle.
+data ImFont
+
+-- | Font configuration handle.
+data ImFontConfig
+
+-- | Glyph ranges builder handle.
+data ImFontGlyphRangesBuilder
+
+-- | Opaque DrawList handle.
+data ImDrawList
+
+-- | 'DearImGui.Raw.ListClipper.ListClipper' pointer tag.
+data ImGuiListClipper
+
+-- | A unique ID used by widgets (typically the result of hashing a stack of string)
+--   unsigned Integer (same as ImU32)
+type ImGuiID = ImU32
+
+-- | 32-bit unsigned integer (often used to store packed colors).
+type ImU32 = Word32
+
+type ImS16 = Int16
+
+-- | Single wide character (used mostly in glyph management)
+#ifdef IMGUI_USE_WCHAR32
+type ImWchar = Word32
+#else
+type ImWchar = Word16
+#endif
+
+--------------------------------------------------------------------------------
+
+-- | Sorting specifications for a table (often handling sort specs for a single column, occasionally more)
+--   Obtained by calling TableGetSortSpecs().
+--   When @SpecsDirty == true@ you can sort your data. It will be true with sorting specs have changed since last call, or the first time.
+--   Make sure to set @SpecsDirty = false@ after sorting, else you may wastefully sort your data every frame!
+data ImGuiTableSortSpecs = ImGuiTableSortSpecs
+  { specs      :: Ptr ImGuiTableColumnSortSpecs
+  , specsCount :: CInt
+  , specsDirty :: CBool
+  } deriving (Show, Eq)
+
+instance Storable ImGuiTableSortSpecs where
+  sizeOf _ =
+    sizeOf (undefined :: Ptr ImGuiTableColumnSortSpecs) +
+    sizeOf (undefined :: CInt) +
+    sizeOf (undefined :: CBool)
+
+  alignment _ =
+    alignment nullPtr
+
+  poke ptr ImGuiTableSortSpecs{..} = do
+    let specsPtr = castPtr ptr
+    poke specsPtr specs
+
+    let specsCountPtr = castPtr $ specsPtr `plusPtr` sizeOf specs
+    poke specsCountPtr specsCount
+
+    let specsDirtyPtr = castPtr $ specsCountPtr `plusPtr` sizeOf specsCount
+    poke specsDirtyPtr specsDirty
+
+  peek ptr = do
+    let specsPtr = castPtr ptr
+    specs <- peek specsPtr
+
+    let specsCountPtr = castPtr $ specsPtr `plusPtr` sizeOf specs
+    specsCount <- peek specsCountPtr
+
+    let specsDirtyPtr = castPtr $ specsCountPtr `plusPtr` sizeOf specsCount
+    specsDirty <- peek specsDirtyPtr
+
+    pure ImGuiTableSortSpecs{..}
+
+-- | Sorting specification for one column of a table
+data ImGuiTableColumnSortSpecs = ImGuiTableColumnSortSpecs
+  { columnUserID  :: ImGuiID            -- ^ User id of the column (if specified by a TableSetupColumn() call)
+  , columnIndex   :: ImS16              -- ^ Index of the column
+  , sortOrder     :: ImS16              -- ^ Index within parent ImGuiTableSortSpecs (always stored in order starting from 0, tables sorted on a single criteria will always have a 0 here)
+  , sortDirection :: ImGuiSortDirection -- ^ 'ImGuiSortDirection_Ascending' or 'ImGuiSortDirection_Descending'
+  } deriving (Show, Eq)
+
+instance Storable ImGuiTableColumnSortSpecs where
+  sizeOf _ = 12
+  alignment _ = 4
+
+  poke ptr ImGuiTableColumnSortSpecs{..} = do
+    let columnUserIDPtr = castPtr ptr
+    poke columnUserIDPtr columnUserID
+
+    let columnIndexPtr = castPtr $ columnUserIDPtr `plusPtr` sizeOf columnUserID
+    poke columnIndexPtr columnIndex
+
+    let sortOrderPtr = castPtr $ columnIndexPtr `plusPtr` sizeOf columnIndex
+    poke sortOrderPtr sortOrder
+
+    let sortDirectionPtr = castPtr $ sortOrderPtr `plusPtr` sizeOf sortOrder
+    poke sortDirectionPtr sortDirection
+
+  peek ptr = do
+    let columnUserIDPtr = castPtr ptr
+    columnUserID <- peek columnUserIDPtr
+
+    let columnIndexPtr = castPtr $ columnUserIDPtr `plusPtr` sizeOf columnUserID
+    columnIndex <- peek columnIndexPtr
+
+    let sortOrderPtr = castPtr $ columnIndexPtr `plusPtr` sizeOf columnIndex
+    sortOrder <- peek sortOrderPtr
+
+    let sortDirectionPtr = castPtr $ sortOrderPtr `plusPtr` sizeOf sortOrder
+    sortDirection' <- peek sortDirectionPtr :: IO CInt
+    -- XXX: Specs struct uses trimmed field: @SortDirection : 8@
+    let sortDirection = case sortDirection' .&. 0xFF of
+          0 ->
+            ImGuiSortDirection_None
+          1 ->
+            ImGuiSortDirection_Ascending
+          2 ->
+            ImGuiSortDirection_Descending
+          _ ->
+            error $ "Unexpected value for ImGuiSortDirection: " <> show sortDirection
+
+    pure ImGuiTableColumnSortSpecs{..}

src/DearImGui/Vulkan.hs

@@ -12,11 +12,15 @@ Vulkan backend for Dear ImGui.
 module DearImGui.Vulkan
   ( InitInfo(..)
   , withVulkan
+  , vulkanInit
+  , vulkanShutdown
   , vulkanNewFrame
   , vulkanRenderDrawData
   , vulkanCreateFontsTexture
   , vulkanDestroyFontUploadObjects
   , vulkanSetMinImageCount
+
+  , vulkanAddTexture
   )
   where
 
@@ -28,9 +32,9 @@ import Data.Word
 import Foreign.Marshal.Alloc
   ( alloca )
 import Foreign.Ptr
-  ( Ptr, freeHaskellFunPtr, nullPtr )
+  ( FunPtr, Ptr, freeHaskellFunPtr, nullPtr )
 import Foreign.Storable
-  ( Storable(poke) )
+  ( poke )
 
 -- inline-c
 import qualified Language.C.Inline as C
@@ -83,7 +87,18 @@ data InitInfo =
 
 -- | Wraps @ImGui_ImplVulkan_Init@ and @ImGui_ImplVulkan_Shutdown@.
 withVulkan :: MonadUnliftIO m => InitInfo -> Vulkan.RenderPass -> ( Bool -> m a ) -> m a
-withVulkan ( InitInfo {..} ) renderPass action = do
+withVulkan initInfo renderPass action =
+  bracket
+    ( vulkanInit initInfo renderPass )
+    vulkanShutdown
+    ( \ ( _, initResult ) -> action initResult )
+
+-- | Wraps @ImGui_ImplVulkan_Init@.
+--
+-- Use 'vulkanShutdown' to clean up on shutdown.
+-- Prefer using 'withVulkan' when possible, as it automatically handles cleanup.
+vulkanInit :: MonadIO m => InitInfo -> Vulkan.RenderPass -> m (FunPtr (Vulkan.Result -> IO ()), Bool)
+vulkanInit ( InitInfo {..} ) renderPass = do
   let
     instancePtr :: Ptr Vulkan.Instance_T
     instancePtr = Vulkan.instanceHandle instance'
@@ -97,38 +112,41 @@ withVulkan ( InitInfo {..} ) renderPass action = do
     withCallbacks f = case mbAllocator of
       Nothing        -> f nullPtr
       Just callbacks -> alloca ( \ ptr -> poke ptr callbacks *> f ptr )
-  bracket
-    ( liftIO do
-        checkResultFunPtr <- $( C.mkFunPtr [t| Vulkan.Result -> IO () |] ) checkResult
-        initResult <- withCallbacks \ callbacksPtr ->
-            [C.block| bool {
-              ImGui_ImplVulkan_InitInfo initInfo;
-              VkInstance instance = { $( VkInstance_T* instancePtr ) };
-              initInfo.Instance = instance;
-              VkPhysicalDevice physicalDevice = { $( VkPhysicalDevice_T* physicalDevicePtr ) };
-              initInfo.PhysicalDevice = physicalDevice;
-              VkDevice device = { $( VkDevice_T* devicePtr ) };
-              initInfo.Device = device;
-              initInfo.QueueFamily = $(uint32_t queueFamily);
-              VkQueue queue = { $( VkQueue_T* queuePtr ) };
-              initInfo.Queue = queue;
-              initInfo.PipelineCache = $(VkPipelineCache pipelineCache);
-              initInfo.DescriptorPool = $(VkDescriptorPool descriptorPool);
-              initInfo.Subpass = $(uint32_t subpass);
-              initInfo.MinImageCount = $(uint32_t minImageCount);
-              initInfo.ImageCount = $(uint32_t imageCount);
-              initInfo.MSAASamples = $(VkSampleCountFlagBits msaaSamples);
-              initInfo.Allocator = $(VkAllocationCallbacks* callbacksPtr);
-              initInfo.CheckVkResultFn = $( void (*checkResultFunPtr)(VkResult) );
-              return ImGui_ImplVulkan_Init(&initInfo, $(VkRenderPass renderPass) );
-            }|]
-        pure ( checkResultFunPtr, initResult /= 0 )
-    )
-    ( \ ( checkResultFunPtr, _ ) -> liftIO do
-      [C.exp| void { ImGui_ImplVulkan_Shutdown(); } |]
-      freeHaskellFunPtr checkResultFunPtr
-    )
-    ( \ ( _, initResult ) -> action initResult )
+  liftIO do
+    checkResultFunPtr <- $( C.mkFunPtr [t| Vulkan.Result -> IO () |] ) checkResult
+    initResult <- withCallbacks \ callbacksPtr ->
+        [C.block| bool {
+          ImGui_ImplVulkan_InitInfo initInfo;
+          VkInstance instance = { $( VkInstance_T* instancePtr ) };
+          initInfo.Instance = instance;
+          VkPhysicalDevice physicalDevice = { $( VkPhysicalDevice_T* physicalDevicePtr ) };
+          initInfo.PhysicalDevice = physicalDevice;
+          VkDevice device = { $( VkDevice_T* devicePtr ) };
+          initInfo.Device = device;
+          initInfo.QueueFamily = $(uint32_t queueFamily);
+          VkQueue queue = { $( VkQueue_T* queuePtr ) };
+          initInfo.Queue = queue;
+          initInfo.PipelineCache = $(VkPipelineCache pipelineCache);
+          initInfo.DescriptorPool = $(VkDescriptorPool descriptorPool);
+          initInfo.Subpass = $(uint32_t subpass);
+          initInfo.MinImageCount = $(uint32_t minImageCount);
+          initInfo.ImageCount = $(uint32_t imageCount);
+          initInfo.MSAASamples = $(VkSampleCountFlagBits msaaSamples);
+          initInfo.Allocator = $(VkAllocationCallbacks* callbacksPtr);
+          initInfo.CheckVkResultFn = $( void (*checkResultFunPtr)(VkResult) );
+          initInfo.UseDynamicRendering = false;
+          // TODO: initInfo.ColorAttachmentFormat
+          return ImGui_ImplVulkan_Init(&initInfo, $(VkRenderPass renderPass) );
+        }|]
+    pure ( checkResultFunPtr, initResult /= 0 )
+
+-- | Wraps @ImGui_ImplVulkan_Shutdown@.
+--
+-- Counterpart to 'vulkanInit', for clean-up.
+vulkanShutdown :: MonadIO m => (FunPtr a, b) -> m ()
+vulkanShutdown ( checkResultFunPtr, _ ) = liftIO do
+  [C.exp| void { ImGui_ImplVulkan_Shutdown(); } |]
+  freeHaskellFunPtr checkResultFunPtr
 
 -- | Wraps @ImGui_ImplVulkan_NewFrame@.
 vulkanNewFrame :: MonadIO m => m ()
@@ -170,3 +188,16 @@ vulkanDestroyFontUploadObjects = liftIO do
 vulkanSetMinImageCount :: MonadIO m => Word32 -> m ()
 vulkanSetMinImageCount minImageCount = liftIO do
   [C.exp| void { ImGui_ImplVulkan_SetMinImageCount($(uint32_t minImageCount)); } |]
+
+-- | Wraps @ImGui_ImplVulkan_AddTexture@.
+vulkanAddTexture :: MonadIO m => Vulkan.Sampler -> Vulkan.ImageView -> Vulkan.ImageLayout -> m Vulkan.DescriptorSet
+vulkanAddTexture sampler imageView imageLayout = liftIO do
+  [C.block|
+    VkDescriptorSet {
+      return ImGui_ImplVulkan_AddTexture(
+        $(VkSampler sampler),
+        $(VkImageView imageView),
+        $(VkImageLayout imageLayout)
+      );
+    }
+  |]

src/DearImGui/Vulkan/Types.hs

@@ -31,6 +31,10 @@ vulkanTypesTable = Map.fromList
   , ( C.TypeName "VkRenderPass"         , [t| Vulkan.RenderPass          |] )
   , ( C.TypeName "VkResult"             , [t| Vulkan.Result              |] )
   , ( C.TypeName "VkSampleCountFlagBits", [t| Vulkan.SampleCountFlagBits |] )
+  , ( C.TypeName "VkSampler"            , [t| Vulkan.Sampler             |] )
+  , ( C.TypeName "VkImageView"          , [t| Vulkan.ImageView           |] )
+  , ( C.TypeName "VkImageLayout"        , [t| Vulkan.ImageLayout         |] )
+  , ( C.TypeName "VkDescriptorSet"      , [t| Vulkan.DescriptorSet       |] )
   ]
 
 vulkanCtx :: C.Context