Prepare 1.3.0 (#120)

* Separate font utils, add glyph support (#113)
* Implement font glyph ranges builder
* Implement raw font config binds
* Implement font atlas module
* Rewrite font altas rebuilder in Managed

.github/workflows/build.yaml

@@ -9,13 +9,14 @@ jobs:
           persist-credentials: false
           submodules: true
 
-    - uses: cachix/install-nix-action@v12
+    - uses: cachix/install-nix-action@v16
       with:
         nix_path: nixpkgs=channel:nixos-unstable
 
-    - uses: cachix/cachix-action@v8
+    - uses: cachix/cachix-action@v10
       with:
         name: hs-dear-imgui
         authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
 
+    - run: nix-build --version      
     - run: nix-build -A hsPkgs.dear-imgui.components.exes

ChangeLog.md

@@ -1,5 +1,20 @@
 # Changelog for dear-imgui
 
+## [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.
@@ -36,3 +51,6 @@ Initial Hackage release based on 1.83.
 [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

Main.hs

@@ -7,6 +7,7 @@ module Main (main) where
 
 import Control.Monad
 import Data.IORef
+import qualified Data.Vector as Vector
 import DearImGui
 import DearImGui.OpenGL3
 import DearImGui.SDL
@@ -131,6 +132,21 @@ loop window checked color slider r pos size' selected tab1Ref tab2Ref = do
 
   endChild
 
+  text "ListClipper"
+  withChildOpen "##fixed" (ImVec2 0 200) True ImGuiWindowFlags_None do
+    let lotsOfItems = Vector.generate 50 (mappend "Item " . show)
+    withListClipper Nothing lotsOfItems text
+
+  text "ListClipper, Haskell-powered"
+  withChildOpen "##infinite" (ImVec2 0 200) True ImGuiWindowFlags_None do
+    let infiniteItems = map (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 . mappend "Item " . show
+
   plotHistogram "A histogram" [ 10, 10, 20, 30, 90 ]
 
   colorPicker3 "Test" color

README.md

@@ -54,38 +54,35 @@ main = do
 
   runManaged do
     -- Create a window using SDL. As we're using OpenGL, we need to enable OpenGL too.
-    w <- do
+    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
+    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
   newFrame
 
   -- Build the GUI
-  bracket_ (begin "Hello, ImGui!") end do
+  withWindowOpen "Hello, ImGui!" do
     -- Add a text widget
     text "Hello, ImGui!"
 
@@ -103,12 +100,25 @@ mainLoop w = do
   render
   openGL2RenderDrawData =<< getDrawData
 
-  glSwapWindow w
+  glSwapWindow window
 
-  mainLoop w
+  mainLoop window
 
   where
-    untilNothingM m = m >>= maybe (return ()) (\_ -> untilNothingM m)
+    -- 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
 ```
 
 # Hacking

dear-imgui.cabal

@@ -1,7 +1,7 @@
 cabal-version: 3.0
 
 name: dear-imgui
-version: 1.2.0
+version: 1.3.0
 author: Oliver Charles
 maintainer: ollie@ocharles.org.uk, aenor.realm@gmail.com
 license: BSD-3-Clause
@@ -24,10 +24,45 @@ extra-source-files:
   imgui/imconfig.h,
   imgui/LICENSE.txt
 
+common build-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 debug mode.
+  default:
+    False
+  manual:
+    True
+
 flag opengl2
   description:
     Enable OpenGL 2 backend.
@@ -82,8 +117,6 @@ common common
         >= 4.12 && < 4.17
   default-language:
       Haskell2010
-  ghc-options:
-      -Wall
 
 library
   import: common
@@ -91,19 +124,25 @@ library
     src
   exposed-modules:
     DearImGui
+    DearImGui.FontAtlas
     DearImGui.Raw
+    DearImGui.Raw.DrawList
+    DearImGui.Raw.Font
+    DearImGui.Raw.Font.Config
+    DearImGui.Raw.Font.GlyphRanges
+    DearImGui.Raw.ListClipper
+    DearImGui.Raw.IO
   other-modules:
     DearImGui.Context
     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++
   include-dirs:
@@ -116,6 +155,7 @@ library
     , inline-c-cpp
     , StateVar
     , unliftio
+    , vector
 
   if flag(opengl2)
     exposed-modules:
@@ -218,7 +258,7 @@ library dear-imgui-generator
     , inline-c
         >= 0.9.0.0 && < 0.10
     , megaparsec
-        >= 9.0 && < 9.1
+        >= 9.0 && < 9.3
     , parser-combinators
         >= 1.2.0 && < 1.4
     , scientific
@@ -230,38 +270,45 @@ library dear-imgui-generator
     , transformers
         >= 0.5.6 && < 0.6
     , unordered-containers
-        >= 0.2.11 && < 0.2.15
+        >= 0.2.11 && < 0.3
 
 executable test
-  import: common
+  import: common, build-flags
   main-is: Main.hs
   default-language: Haskell2010
-  ghc-options: -Wall
   if (!flag(examples) || !flag(sdl) || !flag(opengl2))
     buildable: False
   else
-    build-depends: base, sdl2, gl, dear-imgui
+    build-depends: base, sdl2, gl, dear-imgui, vector
 
 executable glfw
+  import: common, build-flags
   main-is: Main.hs
   hs-source-dirs: examples/glfw
   default-language: Haskell2010
-  ghc-options: -Wall
   if (!flag(examples) || !flag(glfw) || !flag(opengl2))
     buildable: False
   else
     build-depends: base, GLFW-b, gl, dear-imgui, managed
 
 executable readme
-  import: common
+  import: common, build-flags
   main-is: Readme.hs
   hs-source-dirs: examples
   build-depends: sdl2, gl, dear-imgui, managed
   if (!flag(examples) || !flag(sdl) || !flag(opengl2))
     buildable: False
 
+executable fonts
+  import: common, build-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
+  import: common, build-flags
   main-is: Image.hs
   hs-source-dirs: examples/sdl
   build-depends: sdl2, gl, dear-imgui, managed, vector
@@ -269,12 +316,11 @@ executable image
     buildable: False
 
 executable vulkan
-  import: common
+  import: common, build-flags
   main-is: Main.hs
   other-modules: Attachments, Backend, Input, Util
   hs-source-dirs: examples/vulkan
   default-language: Haskell2010
-  ghc-options: -Wall
   if (!flag(examples) || !flag(sdl) || !flag(vulkan))
     buildable: False
   else

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;

examples/Readme.hs

@@ -45,10 +45,7 @@ main = do
 
 
 mainLoop :: Window -> IO ()
-mainLoop window = do
-  -- Process the event loop
-  untilNothingM pollEventWithImGui
-
+mainLoop window = unlessQuit do
   -- Tell ImGui we're starting a new frame
   openGL2NewFrame
   sdl2NewFrame
@@ -78,4 +75,17 @@ mainLoop window = do
   mainLoop window
 
   where
-    untilNothingM m = m >>= maybe (return ()) (\_ -> untilNothingM m)
+    -- 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

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/sdl/Image.hs

@@ -14,6 +14,7 @@ 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
@@ -134,18 +135,18 @@ mainLoop window textures flag = unlessQuit do
   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
 
-      let texture = if flag then fst textures else snd textures
-
-      -- Drawing images require some backend-specific code.
-      -- Meanwhile, we have to deal with raw binding.
-      let openGLtextureID = intPtrToPtr $ fromIntegral $ textureID texture
-
+      -- Using imageButton
       Foreign.with (textureSize texture) \sizePtr ->
         Foreign.with (ImVec2 0 0) \uv0Ptr ->
           Foreign.with (ImVec2 1 1) \uv1Ptr ->
@@ -155,6 +156,19 @@ mainLoop window textures flag = unlessQuit do
     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
 

examples/vulkan/Main.hs

@@ -134,12 +134,6 @@ app = do
     ImGui.createContext
     ImGui.destroyContext
 
-  logDebug "Adding fonts"
-  ImGui.clearFontAtlas
-  _default <- ImGui.addFontDefault
-  _custom <- ImGui.addFontFromFileTTF "imgui/misc/fonts/ProggyTiny.ttf" 10
-  ImGui.buildFontAtlas
-
   let
     preferredFormat :: Vulkan.SurfaceFormatKHR
     preferredFormat =

src/DearImGui.hs

@@ -3,6 +3,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE PatternSynonyms #-}
@@ -54,6 +55,7 @@ module DearImGui
 
     -- ** Utilities
 
+  , Raw.getWindowDrawList
   , Raw.getWindowPos
   , Raw.getWindowSize
   , Raw.getWindowWidth
@@ -84,6 +86,11 @@ module DearImGui
   , pushStyleVar
   , popStyleVar
 
+  , withFont
+  , Raw.Font.pushFont
+  , Raw.Font.popFont
+  , Raw.Font.Font
+
     -- * Cursor/Layout
   , Raw.separator
   , Raw.sameLine
@@ -172,11 +179,11 @@ module DearImGui
   , inputTextMultiline
   , inputTextWithHint
 
-    -- * Color Editor/Picker
+    -- ** Color Editor/Picker
   , colorPicker3
   , colorButton
 
-    -- * Trees
+    -- ** Trees
   , treeNode
   , treePush
   , Raw.treePop
@@ -187,7 +194,7 @@ module DearImGui
     -- ** List Boxes
   , listBox
 
-    -- * Data Plotting
+    -- ** Data Plotting
   , plotHistogram
 
     -- ** Menus
@@ -221,7 +228,7 @@ module DearImGui
   , tabItemButton
   , setTabItemClosed
 
-    -- * Tooltips
+    -- ** Tooltips
   , withTooltip
   , Raw.beginTooltip
   , Raw.endTooltip
@@ -245,12 +252,17 @@ module DearImGui
   , Raw.wantCaptureMouse
   , Raw.wantCaptureKeyboard
 
-    -- * Fonts
-  , Raw.Font
-  , addFontFromFileTTF
-  , Raw.addFontDefault
-  , Raw.buildFontAtlas
-  , Raw.clearFontAtlas
+    -- * Utilities
+
+    -- ** ListClipper
+  , withListClipper
+  , ClipItems(..)
+  , ClipRange(..)
+
+    -- ** Miscellaneous
+  , Raw.getBackgroundDrawList
+  , Raw.getForegroundDrawList
+  , Raw.imCol32
 
     -- * Types
   , module DearImGui.Enums
@@ -273,6 +285,9 @@ import System.IO
 -- dear-imgui
 import DearImGui.Enums
 import DearImGui.Structs
+import qualified DearImGui.Raw as Raw
+import qualified DearImGui.Raw.Font as Raw.Font
+import qualified DearImGui.Raw.ListClipper as Raw.ListClipper
 
 -- managed
 import qualified Control.Monad.Managed as Managed
@@ -289,8 +304,10 @@ import Control.Monad.IO.Class
 import UnliftIO (MonadUnliftIO)
 import UnliftIO.Exception (bracket, bracket_)
 
-import qualified DearImGui.Raw as Raw
-
+-- vector
+import qualified Data.Vector as V
+import qualified Data.Vector.Storable as VS
+import qualified Data.Vector.Unboxed as VU
 
 -- | Get the compiled version string e.g. "1.80 WIP" (essentially the value for
 -- @IMGUI_VERSION@ from the compiled version of @imgui.cpp@).
@@ -1672,21 +1689,89 @@ popStyleVar :: (MonadIO m) => Int -> m ()
 popStyleVar n = liftIO do
   Raw.popStyleVar (fromIntegral n)
 
+-- | Render widgets inside the block using provided font.
+withFont :: MonadUnliftIO m => Raw.Font.Font -> m a -> m a
+withFont font = bracket_ (Raw.Font.pushFont font) Raw.Font.popFont
 
--- | Load a font from TTF file.
+-- | Clips a large list of items
 --
--- Specify font path and atlas glyph size.
---
--- Use 'addFontDefault' if you want to retain built-in font too.
---
--- Call 'buildFontAtlas' after adding all the fonts.
---
--- Call backend-specific `CreateFontsTexture` before using 'newFrame'.
-addFontFromFileTTF :: MonadIO m => FilePath -> Float -> m (Maybe Raw.Font)
-addFontFromFileTTF font size = liftIO do
-  res@(Raw.Font ptr) <- withCString font \fontPtr ->
-    Raw.addFontFromFileTTF fontPtr (CFloat size)
-  pure $
-    if castPtr ptr == nullPtr
-      then Nothing
-      else Just res
+-- The requirements on @a@ are that they are all of the same height.
+withListClipper :: (ClipItems t a, MonadUnliftIO m) => Maybe Float -> t a -> (a -> m ()) -> m ()
+withListClipper itemHeight items action =
+  bracket
+    (liftIO $ throwIfNull "withListClipper: ListClipper allocation failed" Raw.ListClipper.new)
+    Raw.ListClipper.delete
+    step
+  where
+    itemHeight' = maybe (-1.0) CFloat itemHeight
+    itemCount' = maybe maxBound fromIntegral (itemCount items)
+
+    step clipper = do
+      Raw.ListClipper.begin clipper itemCount' itemHeight'
+      go clipper
+
+    go clipper = do
+      doStep <- Raw.ListClipper.step clipper
+      when doStep do
+        let
+          startIndex = fromIntegral $ Raw.ListClipper.displayStart clipper
+          endIndex   = fromIntegral $ Raw.ListClipper.displayEnd clipper
+        stepItems action $
+          clipItems startIndex endIndex items
+
+        go clipper
+
+-- | Containers usable with 'ListClipper'.
+class ClipItems t a where
+  itemCount :: t a -> Maybe Int
+  clipItems :: Int -> Int -> t a -> t a
+  stepItems :: Monad m => (a -> m ()) -> t a -> m ()
+
+-- | Unbounded stream of items.
+instance ClipItems [] a where
+  itemCount = const Nothing
+
+  clipItems displayStart displayEnd =
+    take (displayEnd - displayStart) . drop displayStart
+
+  stepItems = mapM_
+
+instance ClipItems V.Vector a where
+  itemCount = Just . V.length
+
+  clipItems displayStart displayEnd =
+    V.slice displayStart (displayEnd - displayStart)
+
+  stepItems = V.mapM_
+
+instance Storable a => ClipItems VS.Vector a where
+  itemCount = Just . VS.length
+
+  clipItems displayStart displayEnd =
+    VS.slice displayStart (displayEnd - displayStart)
+
+  stepItems = VS.mapM_
+
+instance VU.Unbox a => ClipItems VU.Vector a where
+  itemCount = Just . VU.length
+
+  clipItems displayStart displayEnd =
+    VU.slice displayStart (displayEnd - displayStart)
+
+  stepItems = VU.mapM_
+
+-- | ClipList helper for arbitrary unmaterialized ranges.
+data ClipRange a = ClipRange a a
+  deriving (Eq, Ord, Show)
+
+instance (Ord a, Enum a, Num a) => ClipItems ClipRange a where
+  itemCount (ClipRange _begin end) =
+    Just $ fromEnum end
+
+  clipItems clipBegin clipEnd (ClipRange oldBegin oldEnd) =
+    ClipRange
+      (toEnum $ max clipBegin $ fromEnum oldBegin)
+      (toEnum $ min clipEnd $ fromEnum oldEnd)
+
+  stepItems action (ClipRange start end) =
+    mapM_ action [start .. end - 1]

src/DearImGui/Context.hs

@@ -33,7 +33,13 @@ imguiContext = mempty
       [ ( TypeName "ImVec2", [t| ImVec2 |] )
       , ( TypeName "ImVec3", [t| ImVec3 |] )
       , ( TypeName "ImVec4", [t| ImVec4 |] )
+      , ( TypeName "ImU32", [t| ImU32 |] )
+      , ( 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 |] )
       ]
   }

src/DearImGui/FontAtlas.hs

@@ -0,0 +1,501 @@
+{-# 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.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 :: String -> RangesBuilderSetup
+addText str =
+  RangesBuilderSetup \builder ->
+    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/Raw.hs

@@ -49,6 +49,7 @@ module DearImGui.Raw
 
     -- ** Utilities
 
+  , getWindowDrawList
   , getWindowPos
   , getWindowSize
   , getWindowWidth
@@ -89,6 +90,7 @@ module DearImGui.Raw
   , beginGroup
   , endGroup
   , setCursorPos
+  , getCursorScreenPos
   , alignTextToFramePadding
 
     -- * Widgets
@@ -209,13 +211,12 @@ module DearImGui.Raw
   , wantCaptureMouse
   , wantCaptureKeyboard
 
-    -- * Fonts in default font atlas
-  , Font(..)
-  , addFontDefault
-  , addFontFromFileTTF
-  , addFontFromMemoryTTF
-  , buildFontAtlas
-  , clearFontAtlas
+    -- * Utilities
+
+    -- ** Miscellaneous
+  , getBackgroundDrawList
+  , getForegroundDrawList
+  , imCol32
 
     -- * Types
   , module DearImGui.Enums
@@ -228,12 +229,15 @@ import Control.Monad.IO.Class
   ( MonadIO, liftIO )
 import Foreign
 import Foreign.C
+import System.IO.Unsafe
+  ( unsafePerformIO )
 
 -- dear-imgui
 import DearImGui.Context
   ( imguiContext )
 import DearImGui.Enums
 import DearImGui.Structs
+import DearImGui.Raw.DrawList (DrawList(..))
 
 -- inline-c
 import qualified Language.C.Inline as C
@@ -1264,6 +1268,19 @@ isItemHovered :: (MonadIO m) => m Bool
 isItemHovered = liftIO do
   (0 /=) <$> [C.exp| bool { IsItemHovered() } |]
 
+
+-- | Get draw list associated to the current window.
+getWindowDrawList :: (MonadIO m) => m DrawList
+getWindowDrawList = liftIO do
+  DrawList <$> [C.exp|
+    ImDrawList* {
+      GetWindowDrawList()
+    }
+  |]
+
+-- | Get current window position in screen space.
+--
+-- Useful if you want to do your own drawing via the "DrawList" API.
 getWindowPos :: (MonadIO m) => m ImVec2
 getWindowPos = liftIO do
   C.withPtr_ \ptr ->
@@ -1445,6 +1462,21 @@ setCursorPos :: (MonadIO m) => Ptr ImVec2 -> m ()
 setCursorPos posPtr = liftIO do
   [C.exp| void { SetCursorPos(*$(ImVec2* posPtr)) } |]
 
+-- | Cursor position in absolute coordinates.
+--
+-- Useful to work with 'DrawList' API.
+--
+-- Generally top-left == @GetMainViewport()->Pos == (0,0)@ in single viewport mode,
+-- and bottom-right == @GetMainViewport()->Pos+Size == io.DisplaySize@ in single-viewport mode.
+getCursorScreenPos :: (MonadIO m) => m ImVec2
+getCursorScreenPos = liftIO do
+  C.withPtr_ \ptr ->
+    [C.block|
+      void {
+        *$(ImVec2 * ptr) = GetCursorScreenPos();
+      }
+    |]
+
 
 -- | Modify a style color by pushing to the shared stack. always use this if you modify the style after `newFrame`
 --
@@ -1523,53 +1555,40 @@ wantCaptureKeyboard :: MonadIO m => m Bool
 wantCaptureKeyboard = liftIO do
   (0 /=) <$> [C.exp| bool { GetIO().WantCaptureKeyboard } |]
 
-
--- | Wraps @ImFont*@.
-newtype Font = Font (Ptr ImFont)
-
-addFontDefault :: MonadIO m => m Font
-addFontDefault = liftIO do
-  Font <$> [C.block|
-    ImFont* {
-      return GetIO().Fonts->AddFontDefault();
+-- | This draw list will be the first rendering one.
+--
+-- Useful to quickly draw shapes/text behind dear imgui contents.
+getBackgroundDrawList :: (MonadIO m) => m DrawList
+getBackgroundDrawList = liftIO do
+  DrawList <$> [C.exp|
+    ImDrawList* {
+      GetBackgroundDrawList()
     }
   |]
 
-addFontFromFileTTF :: MonadIO m => CString -> CFloat -> m Font
-addFontFromFileTTF filenamePtr sizePixels = liftIO do
-  Font <$> [C.block|
-    ImFont* {
-      return GetIO().Fonts->AddFontFromFileTTF(
-        $(char* filenamePtr),
-        $(float sizePixels));
+--  | This draw list will be the last rendered one.
+--
+-- Useful to quickly draw shapes/text over dear imgui contents.
+getForegroundDrawList :: (MonadIO m) => m DrawList
+getForegroundDrawList = liftIO do
+  DrawList <$> [C.exp|
+    ImDrawList* {
+      GetForegroundDrawList()
     }
   |]
 
--- | Transfer a buffer with TTF data to font atlas builder.
-addFontFromMemoryTTF :: MonadIO m => CStringLen -> CFloat -> m Font
-addFontFromMemoryTTF (castPtr -> fontDataPtr, fromIntegral -> fontSize) sizePixels = liftIO do
-  Font <$> [C.block|
-    ImFont* {
-      return GetIO().Fonts->AddFontFromMemoryTTF(
-        $(void* fontDataPtr),
-        $(int fontSize),
-        $(float sizePixels)
-      );
-    }
-  |]
-
-buildFontAtlas :: MonadIO m => m ()
-buildFontAtlas = liftIO do
-  [C.block|
-    void {
-      GetIO().Fonts->Build();
-    }
-  |]
-
-clearFontAtlas :: MonadIO m => m ()
-clearFontAtlas = liftIO do
-  [C.block|
-    void {
-      GetIO().Fonts->Clear();
+-- | Generate 32-bit encoded colors using DearImgui macros.
+--
+-- Follows @IMGUI_USE_BGRA_PACKED_COLOR@ define to put bytes in appropriate positions.
+imCol32 :: CUChar -> CUChar -> CUChar -> CUChar -> ImU32
+imCol32 r g b a = unsafePerformIO
+  [C.exp|
+    ImU32 {
+      IM_COL32(
+        $(unsigned char r),
+        $(unsigned char g),
+        $(unsigned char b),
+        $(unsigned char a)
+      )
     }
   |]

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
+
+    -- $stateful
+  , pathClear
+  , pathLineTo
+  , pathLineToMergeDuplicate
+  , pathFillConvex
+  , pathStroke
+
+  , pathArcTo
+  , pathArcToFast
+
+  , pathBezierCubicCurveTo
+  , pathBezierQuadraticCurveTo
+
+  , pathRect
+
+    -- * Advanced
+
+  -- , addCallback
+  , addDrawCmd
+  , cloneOutput
+
+    -- * Internal state
+
+  , pushClipRect
+  , pushClipRectFullScreen
+  , popClipRect
+  , getClipRectMin
+  , getClipRectMax
+
+  , pushTextureID
+  , popTextureID
+  )
+  where
+
+import Control.Monad.IO.Class
+  ( MonadIO, liftIO )
+import Foreign hiding (new)
+import Foreign.C
+
+-- dear-imgui
+import DearImGui.Context
+  ( imguiContext )
+import DearImGui.Enums
+import DearImGui.Structs
+
+-- inline-c
+import qualified Language.C.Inline as C
+
+-- inline-c-cpp
+import qualified Language.C.Inline.Cpp as Cpp
+
+C.context (Cpp.cppCtx <> C.bsCtx <> imguiContext)
+C.include "imgui.h"
+Cpp.using "namespace ImGui"
+
+-- | A single draw command list.
+-- Generally one per window, conceptually you may see this as a dynamic "mesh" builder.
+newtype DrawList = DrawList (Ptr ImDrawList)
+
+new :: MonadIO m => m DrawList
+new = liftIO do
+  DrawList <$> [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.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.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.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 +1,137 @@
+{-# 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.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   WantCaptureMouse;         // Set when Dear ImGui will use mouse inputs, in this case do not dispatch them to your main game/application (either way, always pass on mouse inputs to imgui). (e.g. unclicked mouse is hovering over an imgui window, widget is active, mouse was clicked over an imgui window, etc.).
+bool   WantCaptureKeyboard;      // Set when Dear ImGui will use keyboard inputs, in this case do not dispatch them to your main game/application (either way, always pass keyboard inputs to imgui). (e.g. InputText active, or an imgui window is focused and navigation is enabled, etc.).
+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).
+float  Framerate;                // Rough estimate of application framerate, in frame per second. Solely for convenience. Rolling average estimation based on io.DeltaTime over 120 frames.
+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.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/Structs.hs

@@ -4,6 +4,8 @@
 module DearImGui.Structs where
 
 -- base
+import Data.Word
+  ( Word32, Word16 )
 import Foreign
   ( Storable(..), castPtr, plusPtr )
 
@@ -77,3 +79,22 @@ 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
+
+-- | 32-bit unsigned integer (often used to store packed colors).
+type ImU32 = Word32
+
+-- | Single wide character (used mostly in glyph management)
+type ImWchar = Word16
+-- FIXME: consider IMGUI_USE_WCHAR32