diff --git a/imgui.h b/imgui.h index e9d08a2b..b13f3535 100644 --- a/imgui.h +++ b/imgui.h @@ -32,7 +32,7 @@ Index of this file: // Helpers (ImGuiOnceUponAFrame, ImGuiTextFilter, ImGuiTextBuffer, ImGuiStorage, ImGuiListClipper, ImColor) // Draw List API (ImDrawCallback, ImDrawCmd, ImDrawIdx, ImDrawVert, ImDrawChannel, ImDrawListSplitter, ImDrawListFlags, ImDrawList, ImDrawData) // Font API (ImFontConfig, ImFontGlyph, ImFontGlyphRangesBuilder, ImFontAtlasFlags, ImFontAtlas, ImFont) -// Platform interface for multi-viewport support (ImGuiPlatformMonitor, ImGuiPlatformIO, ImGuiViewport) +// Platform interface for multi-viewport support (ImGuiPlatformIO, ImGuiPlatformMonitor, ImGuiViewportFlags, ImGuiViewport) */ @@ -775,11 +775,12 @@ namespace ImGui IMGUI_API void MemFree(void* ptr); // (Optional) Platform/OS interface for multi-viewport support + // Read comments around the ImGuiPlatformIO structure for more details. // Note: You may use GetWindowViewport() to get the current viewport of the current window. IMGUI_API ImGuiPlatformIO& GetPlatformIO(); // platform/renderer functions, for back-end to setup + viewports list. IMGUI_API ImGuiViewport* GetMainViewport(); // main viewport. same as GetPlatformIO().MainViewport == GetPlatformIO().Viewports[0]. IMGUI_API void UpdatePlatformWindows(); // call in main loop. will call CreateWindow/ResizeWindow/etc. platform functions for each secondary viewport, and DestroyWindow for each inactive viewport. - IMGUI_API void RenderPlatformWindowsDefault(void* platform_arg = NULL, void* renderer_arg = NULL); // call in main loop. will call RenderWindow/SwapBuffers platform functions for each secondary viewport which doesn't have the ImGuiViewportFlags_Minimized flag set. May be reimplemented by user for custom rendering needs. + IMGUI_API void RenderPlatformWindowsDefault(void* platform_render_arg = NULL, void* renderer_render_arg = NULL); // call in main loop. will call RenderWindow/SwapBuffers platform functions for each secondary viewport which doesn't have the ImGuiViewportFlags_Minimized flag set. May be reimplemented by user for custom rendering needs. IMGUI_API void DestroyPlatformWindows(); // call DestroyWindow platform functions for all viewports. call from back-end Shutdown() if you need to close platform windows before imgui shutdown. otherwise will be called by DestroyContext(). IMGUI_API ImGuiViewport* FindViewportByID(ImGuiID id); // this is a helper for back-ends. IMGUI_API ImGuiViewport* FindViewportByPlatformHandle(void* platform_handle); // this is a helper for back-ends. the type platform_handle is decided by the back-end (e.g. HWND, MyWindow*, GLFWwindow* etc.) @@ -2392,32 +2393,54 @@ struct ImFont //----------------------------------------------------------------------------- // [BETA] Platform interface for multi-viewport support -// - completely optional, for advanced users! -// - this is used for back-ends aiming to support the seamless creation of multiple viewport (= multiple Platform/OS windows) -// dear imgui manages the viewports, and the back-end create one Platform/OS windows for each secondary viewport. -// - if you are new to dear imgui and trying to integrate it into your engine, you should probably ignore this for now. +//----------------------------------------------------------------------------- +// (Optional) This is completely optional, for advanced users! +// If you are new to Dear ImGui and trying to integrate it into your engine, you can probably ignore this for now. +// +// This feature allows you to seamlessly drag Dear ImGui windows outside of your application viewport. +// This is achieved by creating new Platform/OS windows on the fly, and rendering into them. +// Dear ImGui manages the viewport structures, and the back-end create and maintain one Platform/OS window for each of those viewports. +// +// See Glossary https://github.com/ocornut/imgui/wiki/Glossary for details about some of the terminology. +// See Thread https://github.com/ocornut/imgui/issues/1542 for gifs, news and questions about this evolving feature. +// +// About the coordinates system: +// - When multi-viewports are enabled, all Dear ImGui coordinates become absolute coordinates (same as OS coordinates!) +// - So e.g. ImGui::SetNextWindowPos(ImVec2(0,0)) will position a window relative to your primary monitor! +// - If you want to position windows relative to your main application viewport, use ImGui::GetMainViewport()->Pos as a base position. +// +// Steps to use multi-viewports in your application, when using a default back-end from the examples/ folder: +// - Application: Enable feature with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'. +// - Back-end: The back-end initialization will setup all necessary ImGuiPlatformIO's functions and update monitors info every frame. +// - Application: In your main loop, call ImGui::UpdatePlatformWindows(), ImGui::RenderPlatformWindowsDefault() after EndFrame() or Render(). +// - Application: Fix absolute coordinates used in ImGui::SetWindowPos() or ImGui::SetNextWindowPos() calls. +// +// Steps to use multi-viewports in your application, when using a custom back-end: +// - Important: THIS IS NOT EASY TO DO and comes with many subtleties not described here! +// It's also an experimental feature, so some of the requirements may evolve. +// Consider using default back-ends if you can. Either way, carefully follow and refer to examples/ back-ends for details. +// - Application: Enable feature with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'. +// - Back-end: Hook ImGuiPlatformIO's Platform_* and Renderer_* callbacks (see below). +// Set 'io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports' and 'io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports'. +// Update ImGuiPlatformIO's Monitors list every frame. +// Update MousePos every frame, in absolute coordinates. +// - Application: In your main loop, call ImGui::UpdatePlatformWindows(), ImGui::RenderPlatformWindowsDefault() after EndFrame() or Render(). +// You may skip calling RenderPlatformWindowsDefault() if its API is not convenient for your needs. Read comments below. +// - Application: Fix absolute coordinates used in ImGui::SetWindowPos() or ImGui::SetNextWindowPos() calls. +// +// About ImGui::RenderPlatformWindowsDefault(): +// - This function is a mostly a _helper_ for the common-most cases, and to facilitate using default back-ends. +// - You can check its simple source code to understand what it does. +// It basically iterates secondary viewports and call 4 functions that are setup in ImGuiPlatformIO, if available: +// Platform_RenderWindow(), Renderer_RenderWindow(), Platform_SwapBuffers(), Renderer_SwapBuffers() +// Those functions pointers exists only for the benefit of RenderPlatformWindowsDefault(). +// - If you have very specific rendering needs (e.g. flipping multiple swap-chain simultaneously, unusual sync/threading issues, etc.), +// you may be tempted to ignore RenderPlatformWindowsDefault() and write customized code to perform your renderingg. +// You may decide to setup the platform_io's *RenderWindow and *SwapBuffers pointers and call your functions through those pointers, +// or you may decide to never setup those pointers and call your code directly. They are a convenience, not an obligatory interface. //----------------------------------------------------------------------------- -// (Optional) This is required when enabling multi-viewport. Represent the bounds of each connected monitor/display and their DPI. -// We use this information for multiple DPI support + clamping the position of popups and tooltips so they don't straddle multiple monitors. -struct ImGuiPlatformMonitor -{ - ImVec2 MainPos, MainSize; // Coordinates of the area displayed on this monitor (Min = upper left, Max = bottom right) - ImVec2 WorkPos, WorkSize; // (Optional) Coordinates without task bars / side bars / menu bars. imgui uses this to avoid positioning popups/tooltips inside this region. - float DpiScale; // 1.0f = 96 DPI - ImGuiPlatformMonitor() { MainPos = MainSize = WorkPos = WorkSize = ImVec2(0,0); DpiScale = 1.0f; } -}; - -// (Optional) Setup required only if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) is enabled. -// Access via ImGui::GetPlatformIO(). This is designed so we can mix and match two imgui_impl_xxxx files, -// one for the Platform (~window handling), one for Renderer. Custom engine back-ends will often provide -// both Platform and Renderer interfaces and so may not need to use all functions. -// Platform functions are typically called before their Renderer counterpart, -// apart from Destroy which are called the other way. -// RenderPlatformWindowsDefault() is that helper that iterate secondary viewports and call, in this order: -// Platform_RenderWindow(), Renderer_RenderWindow(), Platform_SwapBuffers(), Renderer_SwapBuffers() -// You may skip using RenderPlatformWindowsDefault() and call your draw/swap functions yourself if you need -// specific behavior for your multi-window rendering. +// (Optional) Access via ImGui::GetPlatformIO() struct ImGuiPlatformIO { //------------------------------------------------------------------ @@ -2425,47 +2448,72 @@ struct ImGuiPlatformIO //------------------------------------------------------------------ // (Optional) Platform functions (e.g. Win32, GLFW, SDL2) - // Most of them are called by ImGui::UpdatePlatformWindows() and ImGui::RenderPlatformWindowsDefault(). - void (*Platform_CreateWindow)(ImGuiViewport* vp); // Create a new platform window for the given viewport - void (*Platform_DestroyWindow)(ImGuiViewport* vp); - void (*Platform_ShowWindow)(ImGuiViewport* vp); // Newly created windows are initially hidden so SetWindowPos/Size/Title can be called on them first - void (*Platform_SetWindowPos)(ImGuiViewport* vp, ImVec2 pos); - ImVec2 (*Platform_GetWindowPos)(ImGuiViewport* vp); - void (*Platform_SetWindowSize)(ImGuiViewport* vp, ImVec2 size); - ImVec2 (*Platform_GetWindowSize)(ImGuiViewport* vp); - void (*Platform_SetWindowFocus)(ImGuiViewport* vp); // Move window to front and set input focus - bool (*Platform_GetWindowFocus)(ImGuiViewport* vp); - bool (*Platform_GetWindowMinimized)(ImGuiViewport* vp); - void (*Platform_SetWindowTitle)(ImGuiViewport* vp, const char* title); - void (*Platform_SetWindowAlpha)(ImGuiViewport* vp, float alpha); // (Optional) Setup window transparency - void (*Platform_UpdateWindow)(ImGuiViewport* vp); // (Optional) Called in UpdatePlatforms(). Optional hook to allow the platform back-end from doing general book-keeping every frame. - void (*Platform_RenderWindow)(ImGuiViewport* vp, void* render_arg); // (Optional) Setup for render - void (*Platform_SwapBuffers)(ImGuiViewport* vp, void* render_arg); // (Optional) Call Present/SwapBuffers (platform side) - float (*Platform_GetWindowDpiScale)(ImGuiViewport* vp); // (Optional) [BETA] (FIXME-DPI) DPI handling: Return DPI scale for this viewport. 1.0f = 96 DPI. - void (*Platform_OnChangedViewport)(ImGuiViewport* vp); // (Optional) [BETA] (FIXME-DPI) DPI handling: Called during Begin() every time the viewport we are outputting into changes, so back-end has a chance to swap fonts to adjust style. - void (*Platform_SetImeInputPos)(ImGuiViewport* vp, ImVec2 pos); // (Optional) Set IME (Input Method Editor, e.g. for Asian languages) input position, so text preview appears over the imgui input box. - int (*Platform_CreateVkSurface)(ImGuiViewport* vp, ImU64 vk_inst, const void* vk_allocators, ImU64* out_vk_surface); // (Optional) For Renderer to call into Platform code + // For reference, the second column shows which function are generally calling the Platform Functions: + // N = ImGui::NewFrame() ~ beginning of the dear imgui frame: read info from platform/OS windows (latest size/position) + // F = ImGui::Begin(), ImGui::EndFrame() ~ during the dear imgui frame + // U = ImGui::UpdatePlatformWindows() ~ after the dear imgui frame: create and update all platform/OS windows + // R = ImGui::RenderPlatformWindowsDefault() ~ render + // D = ImGui::DestroyPlatformWindows() ~ shutdown + // The general idea is that NewFrame() we will read the current Platform/OS state, and UpdatePlatformWindows() will write to it. + // + // The functions are designed so we can mix and match 2 imgui_impl_xxxx files, one for the Platform (~window/input handling), one for Renderer. + // Custom engine back-ends will often provide both Platform and Renderer interfaces and so may not need to use all functions. + // Platform functions are typically called before their Renderer counterpart, apart from Destroy which are called the other way. - // (Optional) Renderer functions (e.g. DirectX, OpenGL3, Vulkan) - void (*Renderer_CreateWindow)(ImGuiViewport* vp); // Create swap chains, frame buffers etc. - void (*Renderer_DestroyWindow)(ImGuiViewport* vp); - void (*Renderer_SetWindowSize)(ImGuiViewport* vp, ImVec2 size); // Resize swap chain, frame buffers etc. - void (*Renderer_RenderWindow)(ImGuiViewport* vp, void* render_arg); // (Optional) Clear targets, Render viewport->DrawData - void (*Renderer_SwapBuffers)(ImGuiViewport* vp, void* render_arg); // (Optional) Call Present/SwapBuffers (renderer side) + // Platform function --------------------------------------------------- Called by ----- + void (*Platform_CreateWindow)(ImGuiViewport* vp); // . . U . . // Create a new platform window for the given viewport + void (*Platform_DestroyWindow)(ImGuiViewport* vp); // N . U . D // + void (*Platform_ShowWindow)(ImGuiViewport* vp); // . . U . . // Newly created windows are initially hidden so SetWindowPos/Size/Title can be called on them before showing the window + void (*Platform_SetWindowPos)(ImGuiViewport* vp, ImVec2 pos); // . . U . . // Set platform window position (given the upper-left corner of client area) + ImVec2 (*Platform_GetWindowPos)(ImGuiViewport* vp); // N . . . . // + void (*Platform_SetWindowSize)(ImGuiViewport* vp, ImVec2 size); // . . U . . // Set platform window client area size (ignoring OS decorations such as OS title bar etc.) + ImVec2 (*Platform_GetWindowSize)(ImGuiViewport* vp); // N . . . . // Get platform window client area size + void (*Platform_SetWindowFocus)(ImGuiViewport* vp); // N . . . . // Move window to front and set input focus + bool (*Platform_GetWindowFocus)(ImGuiViewport* vp); // . . U . . // + bool (*Platform_GetWindowMinimized)(ImGuiViewport* vp); // N . . . . // Get platform window minimized state. When minimized, we generally won't attempt to get/set size and contents will be culled more easily + void (*Platform_SetWindowTitle)(ImGuiViewport* vp, const char* str); // . . U . . // Set platform window title (given an UTF-8 string) + void (*Platform_SetWindowAlpha)(ImGuiViewport* vp, float alpha); // . . U . . // (Optional) Setup window transparency + void (*Platform_UpdateWindow)(ImGuiViewport* vp); // . . U . . // (Optional) Called by UpdatePlatformWindows(). Optional hook to allow the platform back-end from doing general book-keeping every frame. + void (*Platform_RenderWindow)(ImGuiViewport* vp, void* render_arg); // . . . R . // (Optional) Main rendering (platform side! This is often unused, or just setting a "current" context for OpenGL bindings). 'render_arg' is the value passed to RenderPlatformWindowsDefault(). + void (*Platform_SwapBuffers)(ImGuiViewport* vp, void* render_arg); // . . . R . // (Optional) Call Present/SwapBuffers (platform side! This is often unused!). 'render_arg' is the value passed to RenderPlatformWindowsDefault(). + float (*Platform_GetWindowDpiScale)(ImGuiViewport* vp); // N . . . . // (Optional) [BETA] FIXME-DPI: DPI handling: Return DPI scale for this viewport. 1.0f = 96 DPI. + void (*Platform_OnChangedViewport)(ImGuiViewport* vp); // . F . . . // (Optional) [BETA] FIXME-DPI: DPI handling: Called during Begin() every time the viewport we are outputting into changes, so back-end has a chance to swap fonts to adjust style. + void (*Platform_SetImeInputPos)(ImGuiViewport* vp, ImVec2 pos); // . F . . . // (Optional) Set IME (Input Method Editor, e.g. for Asian languages) input position, so text preview appears over the imgui input box. FIXME: The call timing of this is inconsistent because we want to support without multi-viewports. + int (*Platform_CreateVkSurface)(ImGuiViewport* vp, ImU64 vk_inst, const void* vk_allocators, ImU64* out_vk_surface); // (Optional) For a Vulkan Renderer to call into Platform code (since the surface creation needs to tie them both). - // (Optional) List of monitors (updated by: app/back-end, used by: imgui to clamp popups/tooltips within same monitor and not have them straddle monitors) + // (Optional) Renderer functions (e.g. DirectX, OpenGL, Vulkan) + void (*Renderer_CreateWindow)(ImGuiViewport* vp); // . . U . . // Create swap chain, frame buffers etc. (called after Platform_CreateWindow) + void (*Renderer_DestroyWindow)(ImGuiViewport* vp); // N . U . D // Destroy swap chain, frame buffers etc. (called before Platform_DestroyWindow) + void (*Renderer_SetWindowSize)(ImGuiViewport* vp, ImVec2 size); // . . U . . // Resize swap chain, frame buffers etc. (called after Platform_SetWindowSize) + void (*Renderer_RenderWindow)(ImGuiViewport* vp, void* render_arg); // . . . R . // (Optional) Clear framebuffer, setup render target, then render the viewport->DrawData. 'render_arg' is the value passed to RenderPlatformWindowsDefault(). + void (*Renderer_SwapBuffers)(ImGuiViewport* vp, void* render_arg); // . . . R . // (Optional) Call Present/SwapBuffers. 'render_arg' is the value passed to RenderPlatformWindowsDefault(). + + // (Optional) Monitor list + // - Updated by: app/back-end. Update every frame to dynamically support changing monitor or DPI configuration. + // - Used by: dear imgui to query DPI info, clamp popups/tooltips within same monitor and not have them straddle monitors. ImVector Monitors; //------------------------------------------------------------------ // Output - List of viewports to render into platform windows //------------------------------------------------------------------ - // List of viewports (the list is updated by calling ImGui::EndFrame or ImGui::Render) + // Viewports list (the list is updated by calling ImGui::EndFrame or ImGui::Render) + // (in the future we will attempt to organize this feature to remove the need for a "main viewport") ImGuiViewport* MainViewport; // Guaranteed to be == Viewports[0] ImVector Viewports; // Main viewports, followed by all secondary viewports. ImGuiPlatformIO() { memset(this, 0, sizeof(*this)); } // Zero clear }; +// (Optional) This is required when enabling multi-viewport. Represent the bounds of each connected monitor/display and their DPI. +// We use this information for multiple DPI support + clamping the position of popups and tooltips so they don't straddle multiple monitors. +struct ImGuiPlatformMonitor +{ + ImVec2 MainPos, MainSize; // Coordinates of the area displayed on this monitor (Min = upper left, Max = bottom right) + ImVec2 WorkPos, WorkSize; // (Optional) Coordinates without task bars / side bars / menu bars. imgui uses this to avoid positioning popups/tooltips inside this region. + float DpiScale; // 1.0f = 96 DPI + ImGuiPlatformMonitor() { MainPos = MainSize = WorkPos = WorkSize = ImVec2(0, 0); DpiScale = 1.0f; } +}; + // Flags stored in ImGuiViewport::Flags, giving indications to the platform back-ends. enum ImGuiViewportFlags_ { @@ -2498,9 +2546,11 @@ struct ImGuiViewport ImGuiID ParentViewportId; // (Advanced) 0: no parent. Instruct the platform back-end to setup a parent/child relationship between platform windows. // Our design separate the Renderer and Platform back-ends to facilitate combining default back-ends with each others. - // When our create your own back-end for a custom engine, it is possible that both Renderer and Platform will be handled by the same system and you may not need to use all the UserData/Handle fields. - void* RendererUserData; // void* to hold custom data structure for the renderer (e.g. swap chain, framebuffers etc.). - void* PlatformUserData; // void* to hold custom data structure for the OS / platform (e.g. windowing info, render context). + // When our create your own back-end for a custom engine, it is possible that both Renderer and Platform will be handled + // by the same system and you may not need to use all the UserData/Handle fields. + // The library never uses those fields, they are merely storage to facilitate back-end implementation. + void* RendererUserData; // void* to hold custom data structure for the renderer (e.g. swap chain, framebuffers etc.). generally set by your Renderer_CreateWindow function. + void* PlatformUserData; // void* to hold custom data structure for the OS / platform (e.g. windowing info, render context). generally set by your Platform_CreateWindow function. void* PlatformHandle; // void* for FindViewportByPlatformHandle(). (e.g. suggested to use natural platform handle such as HWND, GLFWWindow*, SDL_Window*) void* PlatformHandleRaw; // void* to hold lower-level, platform-native window handle (e.g. the HWND) when using an abstraction layer like GLFW or SDL (where PlatformHandle would be a SDL_Window*) bool PlatformRequestMove; // Platform window requested move (e.g. window was moved by the OS / host window manager, authoritative position will be OS window position)