(Breaking) Default ImTextureID to use a Im64 instead of void* (#1641)

backends/imgui_impl_dx12.cpp

@@ -6,14 +6,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 //  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
 
-// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-// To build this on 32-bit systems:
-// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
-// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
-
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
 // Learn about Dear ImGui:
@@ -446,14 +438,6 @@ static void ImGui_ImplDX12_CreateFontsTexture()
     }
 
     // Store our identifier
-    // READ THIS IF THE STATIC_ASSERT() TRIGGERS:
-    // - Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-    // - This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-    // [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
-    // [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-    // [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-    // [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
-    static_assert(sizeof(ImTextureID) >= sizeof(bd->hFontSrvGpuDescHandle.ptr), "Can't pack descriptor handle into TexID, 32-bit not supported yet.");
     io.Fonts->SetTexID((ImTextureID)bd->hFontSrvGpuDescHandle.ptr);
 }
 

backends/imgui_impl_dx12.h

@@ -6,9 +6,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 //  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
 
-// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-// See imgui_impl_dx12.cpp file for details.
-
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
 // Learn about Dear ImGui:

backends/imgui_impl_vulkan.cpp

@@ -6,14 +6,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 //  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
 
-// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
-// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-// To build this on 32-bit systems and support texture changes:
-// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in our .vcxproj files)
-// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in our batch files)
-
 // The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
 // IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
 

backends/imgui_impl_vulkan.h

@@ -6,9 +6,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 //  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
 
-// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
-// See imgui_impl_vulkan.cpp file for details.
-
 // The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
 // IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
 

docs/CHANGELOG.txt

@@ -36,11 +36,25 @@ HOW TO UPDATE?
 - Please report any issue!
 
 -----------------------------------------------------------------------
- VERSION 1.91.4 WIP
+ VERSION 1.91.4 WIP (In Progress)
 -----------------------------------------------------------------------
 
 Breaking changes:
 
+- The typedef for ImTextureID now defaults to ImU64 instead of void*. (#1641)
+  - This removes the requirement to redefine it for backends which are e.g. storing
+    descriptor sets or other 64-bits structures when building on 32-bits archs.
+    It therefore simplify various building scripts/helpers.
+  - You may have compile-time issues if you were casting to 'void*' instead of 'ImTextureID'
+    when passing your types to functions taking ImTextureID values, e.g. ImGui::Image().
+    In doubt it is almost always better to do an intermediate intptr_t cast, since it
+    allows casting any pointer/integer type without warning:
+    - May warn:     ImGui::Image((void*)MyTextureData, ...);
+    - May warn:     ImGui::Image((void*)(intptr_t)MyTextureData, ...);
+    - Won't warn:   ImGui::Image((ImTextureID)(intptr_t)MyTextureData), ...);
+  - Note that you can always define ImTextureID to be your own high-level structures
+    (with dedicated constructors) if you like.
+
 Other changes:
 
 - IO: added 'void* platform_io.Renderer_RenderState' which is set during the

docs/FAQ.md

@@ -380,36 +380,37 @@ node open/closed state differently. See what makes more sense in your situation!
 Short explanation:
 - Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki).
 - You may use functions such as `ImGui::Image()`, `ImGui::ImageButton()` or lower-level `ImDrawList::AddImage()` to emit draw calls that will use your own textures.
-- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as ImTextureID (void*) value.
-- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason).
+- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as an opaque ImTextureID value.
+- By default ImTextureID can store up to 64-bits. You may `#define` it to a custom type/structure if you need.
+- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason), but the examples linked above may be useful references.
 
 **Please read documentations or tutorials on your graphics API to understand how to display textures on the screen before moving onward.**
 
 Long explanation:
 - Dear ImGui's job is to create "meshes", defined in a renderer-agnostic format made of draw commands and vertices. At the end of the frame, those meshes (ImDrawList) will be displayed by your rendering function. They are made up of textured polygons and the code to render them is generally fairly short (a few dozen lines). In the examples/ folder, we provide functions for popular graphics APIs (OpenGL, DirectX, etc.).
 - Each rendering function decides on a data type to represent "textures". The concept of what is a "texture" is entirely tied to your underlying engine/graphics API.
  We carry the information to identify a "texture" in the ImTextureID type.
-ImTextureID is nothing more than a void*, aka 4/8 bytes worth of data: just enough to store one pointer or integer of your choice.
+ImTextureID default to ImU64 aka 8 bytes worth of data: just enough to store one pointer or integer of your choice.
 Dear ImGui doesn't know or understand what you are storing in ImTextureID, it merely passes ImTextureID values until they reach your rendering function.
 - In the [examples/](https://github.com/ocornut/imgui/tree/master/examples) backends, for each graphics API we decided on a type that is likely to be a good representation for specifying an image from the end-user perspective. This is what the _examples_ rendering functions are using:
 ```cpp
 OpenGL:
-- ImTextureID = GLuint
+- ImTextureID should contains 'GLuint' (GL texture identifier).
 - See ImGui_ImplOpenGL3_RenderDrawData() function in imgui_impl_opengl3.cpp
 ```
 ```cpp
 DirectX9:
-- ImTextureID = LPDIRECT3DTEXTURE9
+- ImTextureID should contain a 'LPDIRECT3DTEXTURE9' (pointer).
 - See ImGui_ImplDX9_RenderDrawData() function in imgui_impl_dx9.cpp
 ```
 ```cpp
 DirectX11:
-- ImTextureID = ID3D11ShaderResourceView*
+- ImTextureID should contain a 'ID3D11ShaderResourceView*' (poiter)
 - See ImGui_ImplDX11_RenderDrawData() function in imgui_impl_dx11.cpp
 ```
 ```cpp
 DirectX12:
-- ImTextureID = D3D12_GPU_DESCRIPTOR_HANDLE
+- ImTextureID should contain a 'D3D12_GPU_DESCRIPTOR_HANDLE' (always 64-bits)
 - See ImGui_ImplDX12_RenderDrawData() function in imgui_impl_dx12.cpp
 ```
 For example, in the OpenGL example backend we store raw OpenGL texture identifier (GLuint) inside ImTextureID.
@@ -421,14 +422,14 @@ If you are starting with OpenGL or DirectX or Vulkan and haven't built much of a
 
 User code may do:
 ```cpp
-// Cast our texture type to ImTextureID / void*
+// Cast our texture type to ImTextureID
 MyTexture* texture = g_CoffeeTableTexture;
-ImGui::Image((void*)texture, ImVec2(texture->Width, texture->Height));
+ImGui::Image((ImTextureID)(intptr_t)texture, ImVec2(texture->Width, texture->Height));
 ```
 The renderer function called after ImGui::Render() will receive that same value that the user code passed:
 ```cpp
-// Cast ImTextureID / void* stored in the draw command as our texture type
-MyTexture* texture = (MyTexture*)pcmd->GetTexID();
+// Cast ImTextureID stored in the draw command as our texture type
+MyTexture* texture = (MyTexture*)(intptr_t)pcmd->GetTexID();
 MyEngineBindTexture2D(texture);
 ```
 Once you understand this design, you will understand that loading image files and turning them into displayable textures is not within the scope of Dear ImGui.
@@ -437,19 +438,19 @@ If you want to display an image file (e.g. PNG file) on the screen, please refer
 
 Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki) to find simplified examples for loading textures with OpenGL, DirectX9 and DirectX11.
 
-C/C++ tip: a void* is pointer-sized storage. You may safely store any pointer or integer into it by casting your value to ImTextureID / void*, and vice-versa.
-Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID / void*.
+C/C++ tip: a u64 is 8 bytes. You may safely store any pointer or integer into it by casting your value to ImTextureID, and vice-versa.
+Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID.
 Here are some examples:
 ```cpp
 GLuint my_tex = XXX;
-void* my_void_ptr;
-my_void_ptr = (void*)(intptr_t)my_tex;                  // cast a GLuint into a void* (we don't take its address! we literally store the value inside the pointer)
-my_tex = (GLuint)(intptr_t)my_void_ptr;                 // cast a void* into a GLuint
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_tex;                     // cast a GLuint into a ImTextureID (we don't take its address! we just copy the address)
+my_tex = (GLuint)(intptr_t)my_imtexid;                          // cast a ImTextureID into a GLuint
 
 ID3D11ShaderResourceView* my_dx11_srv = XXX;
-void* my_void_ptr;
-my_void_ptr = (void*)my_dx11_srv;                       // cast a ID3D11ShaderResourceView* into an opaque void*
-my_dx11_srv = (ID3D11ShaderResourceView*)my_void_ptr;   // cast a void* into a ID3D11ShaderResourceView*
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_dx11_srv;                // cast a ID3D11ShaderResourceView* into an opaque ImTextureID
+my_dx11_srv = (ID3D11ShaderResourceView*)(intptr_t)_my_imtexid; // cast a ImTextureID into a ID3D11ShaderResourceView*
 ```
 Finally, you may call `ImGui::ShowMetricsWindow()` to explore/visualize/understand how the ImDrawList are generated.
 

examples/example_glfw_vulkan/CMakeLists.txt

@@ -42,4 +42,4 @@ file(GLOB sources *.cpp)
 
 add_executable(example_glfw_vulkan ${sources} ${IMGUI_DIR}/backends/imgui_impl_glfw.cpp ${IMGUI_DIR}/backends/imgui_impl_vulkan.cpp ${IMGUI_DIR}/imgui.cpp ${IMGUI_DIR}/imgui_draw.cpp ${IMGUI_DIR}/imgui_demo.cpp ${IMGUI_DIR}/imgui_tables.cpp ${IMGUI_DIR}/imgui_widgets.cpp)
 target_link_libraries(example_glfw_vulkan ${LIBRARIES})
-target_compile_definitions(example_glfw_vulkan PUBLIC -DImTextureID=ImU64)
+

examples/example_glfw_vulkan/build_win32.bat

@@ -7,8 +7,8 @@
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
 
 @set OUT_DIR=Release
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%

examples/example_glfw_vulkan/build_win64.bat

@@ -6,8 +6,8 @@
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
 
 @set OUT_DIR=Release
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%

examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj

@@ -91,7 +91,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -107,7 +107,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -126,7 +126,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -148,7 +148,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>

examples/example_sdl2_vulkan/build_win32.bat

@@ -7,4 +7,4 @@
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console