Backends: SDL_GPU3: changed ImTextureID type from SDL_GPUTextureSamplerBinding* to SDL_GPUTexture*. Added ImGui_ImplSDLGPU3_RenderState. (#8866, #8163, #7998, #7988)

backends/imgui_impl_sdlgpu3.cpp

@@ -2,7 +2,7 @@
 // This needs to be used along with the SDL3 Platform Backend
 
 // Implemented features:
-//  [X] Renderer: User texture binding. Use simply cast a reference to your SDL_GPUTextureSamplerBinding to ImTextureID.
+//  [X] Renderer: User texture binding. Use 'SDL_GPUTexture*' as texture identifier. Read the FAQ about ImTextureID/ImTextureRef! **IMPORTANT** Before 2025/08/08, ImTextureID was a reference to a SDL_GPUTextureSamplerBinding struct.
 //  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 //  [X] Renderer: Texture updates support for dynamic font atlas (ImGuiBackendFlags_RendererHasTextures).
 
@@ -22,6 +22,8 @@
 //   Calling the function is MANDATORY, otherwise the ImGui will not upload neither the vertex nor the index buffer for the GPU. See imgui_impl_sdlgpu3.cpp for more info.
 
 // CHANGELOG
+//  2025-08-08: *BREAKING* Changed ImTextureID type from SDL_GPUTextureSamplerBinding* to SDL_GPUTexture*, which is more natural and easier for user to manage. If you need to change the current sampler, you can access the ImGui_ImplSDLGPU3_RenderState struct. (#8866, #8163, #7998, #7988)
+//  2025-08-08: Expose SamplerDefault and SamplerCurrent in ImGui_ImplSDLGPU3_RenderState. Allow callback to change sampler.
 //  2025-06-25: Mapping transfer buffer for texture update use cycle=true. Fixes artifacts e.g. on Metal backend.
 //  2025-06-11: Added support for ImGuiBackendFlags_RendererHasTextures, for dynamic font atlas. Removed ImGui_ImplSDLGPU3_CreateFontsTexture() and ImGui_ImplSDLGPU3_DestroyFontsTexture().
 //  2025-04-28: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
@@ -39,7 +41,6 @@
 struct ImGui_ImplSDLGPU3_Texture
 {
     SDL_GPUTexture*              Texture = nullptr;
-    SDL_GPUTextureSamplerBinding TextureSamplerBinding = { nullptr, nullptr };
 };
 
 // Reusable buffers used for rendering 1 current in-flight frame, for ImGui_ImplSDLGPU3_RenderDrawData()
@@ -84,12 +85,13 @@ static ImGui_ImplSDLGPU3_Data* ImGui_ImplSDLGPU3_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplSDLGPU3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
-static void ImGui_ImplSDLGPU3_SetupRenderState(ImDrawData* draw_data, SDL_GPUGraphicsPipeline* pipeline, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass * render_pass, ImGui_ImplSDLGPU3_FrameData* fd, uint32_t fb_width, uint32_t fb_height)
+static void ImGui_ImplSDLGPU3_SetupRenderState(ImDrawData* draw_data, ImGui_ImplSDLGPU3_RenderState* render_state, SDL_GPUGraphicsPipeline* pipeline, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass* render_pass, ImGui_ImplSDLGPU3_FrameData* fd, uint32_t fb_width, uint32_t fb_height)
 {
-    //ImGui_ImplSDLGPU3_Data* bd = ImGui_ImplSDLGPU3_GetBackendData();
+    ImGui_ImplSDLGPU3_Data* bd = ImGui_ImplSDLGPU3_GetBackendData();
+    render_state->SamplerCurrent = render_state->SamplerCurrent = bd->TexSampler;
 
     // Bind graphics pipeline
-    SDL_BindGPUGraphicsPipeline(render_pass,pipeline);
+    SDL_BindGPUGraphicsPipeline(render_pass, pipeline);
 
     // Bind Vertex And Index Buffers
     if (draw_data->TotalVtxCount > 0)
@@ -227,12 +229,19 @@ void ImGui_ImplSDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffe
     if (pipeline == nullptr)
         pipeline = bd->Pipeline;
 
-    ImGui_ImplSDLGPU3_SetupRenderState(draw_data, pipeline, command_buffer, render_pass, fd, fb_width, fb_height);
-
     // Will project scissor/clipping rectangles into framebuffer space
     ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
     ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
 
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplSDLGPU3_RenderState render_state;
+    render_state.Device = bd->InitInfo.Device;
+    render_state.SamplerDefault = render_state.SamplerCurrent = bd->TexSampler;
+    platform_io.Renderer_RenderState = &render_state;
+
+    ImGui_ImplSDLGPU3_SetupRenderState(draw_data, &render_state, pipeline, command_buffer, render_pass, fd, fb_width, fb_height);
+
     // Render command lists
     // (Because we merged all buffers into a single one, we maintain our own offset into them)
     int global_vtx_offset = 0;
@@ -247,7 +256,7 @@ void ImGui_ImplSDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffe
                 // User callback, registered via ImDrawList::AddCallback()
                 // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
-                    ImGui_ImplSDLGPU3_SetupRenderState(draw_data, pipeline, command_buffer, render_pass, fd, fb_width, fb_height);
+                    ImGui_ImplSDLGPU3_SetupRenderState(draw_data, &render_state, pipeline, command_buffer, render_pass, fd, fb_width, fb_height);
                 else
                     pcmd->UserCallback(draw_list, pcmd);
             }
@@ -274,9 +283,14 @@ void ImGui_ImplSDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffe
                 SDL_SetGPUScissor(render_pass,&scissor_rect);
 
                 // Bind DescriptorSet with font or user texture
-                SDL_BindGPUFragmentSamplers(render_pass, 0, (SDL_GPUTextureSamplerBinding*)pcmd->GetTexID(), 1);
+                SDL_GPUTextureSamplerBinding texture_sampler_binding;
+                texture_sampler_binding.texture = (SDL_GPUTexture*)(intptr_t)pcmd->GetTexID();
+                texture_sampler_binding.sampler = render_state.SamplerCurrent;
+                SDL_BindGPUFragmentSamplers(render_pass, 0, &texture_sampler_binding, 1);
 
                 // Draw
+                // **IF YOU GET A CRASH HERE** In 1.92.2 on 2025/08/08 we have changed ImTextureID to store 'SDL_GPUTexture*' instead of storing 'SDL_GPUTextureSamplerBinding'.
+                // Any code loading custom texture using this backend needs to be updated.
                 SDL_DrawGPUIndexedPrimitives(render_pass, pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
             }
         }
@@ -334,12 +348,10 @@ void ImGui_ImplSDLGPU3_UpdateTexture(ImTextureData* tex)
         texture_info.sample_count = SDL_GPU_SAMPLECOUNT_1;
 
         backend_tex->Texture = SDL_CreateGPUTexture(v->Device, &texture_info);
-        backend_tex->TextureSamplerBinding.texture = backend_tex->Texture;
-        backend_tex->TextureSamplerBinding.sampler = bd->TexSampler;
         IM_ASSERT(backend_tex->Texture && "Failed to create font texture, call SDL_GetError() for more info");
 
         // Store identifiers
-        tex->SetTexID((ImTextureID)(intptr_t)&backend_tex->TextureSamplerBinding);
+        tex->SetTexID((ImTextureID)(intptr_t)backend_tex->Texture);
         tex->BackendUserData = backend_tex;
     }
 

backends/imgui_impl_sdlgpu3.h

@@ -2,7 +2,7 @@
 // This needs to be used along with the SDL3 Platform Backend
 
 // Implemented features:
-//  [X] Renderer: User texture binding. Use simply cast a reference to your SDL_GPUTextureSamplerBinding to ImTextureID.
+//  [X] Renderer: User texture binding. Use 'SDL_GPUTexture*' as texture identifier. Read the FAQ about ImTextureID/ImTextureRef! **IMPORTANT** Before 2025/08/08, ImTextureID was a reference to a SDL_GPUTextureSamplerBinding struct.
 //  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 //  [X] Renderer: Texture updates support for dynamic font atlas (ImGuiBackendFlags_RendererHasTextures).
 
@@ -49,4 +49,14 @@ IMGUI_IMPL_API void     ImGui_ImplSDLGPU3_DestroyDeviceObjects();
 // (Advanced) Use e.g. if you need to precisely control the timing of texture updates (e.g. for staged rendering), by setting ImDrawData::Textures = NULL to handle this manually.
 IMGUI_IMPL_API void     ImGui_ImplSDLGPU3_UpdateTexture(ImTextureData* tex);
 
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplSDLGPU3_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplSDLGPU3_RenderState
+{
+    SDL_GPUDevice*      Device;
+    SDL_GPUSampler*     SamplerDefault;     // Default sampler (bilinear filtering)
+    SDL_GPUSampler*     SamplerCurrent;     // Current sampler (may be changed by callback)
+};
+
 #endif // #ifndef IMGUI_DISABLE

docs/CHANGELOG.txt

@@ -43,6 +43,9 @@ Breaking Changes:
 
 - Tabs: Renamed ImGuiTabBarFlags_FittingPolicyResizeDown to ImGuiTabBarFlags_FittingPolicyShrink.
   Kept inline redirection enum (will obsolete). (#261, #351)
+- Backends: SDL_GPU3: changed ImTextureID type from SDL_GPUTextureSamplerBinding* to SDL_GPUTexture*,
+  which is more natural and easier for user to manage. If you need to change the current sampler,
+  you can access the ImGui_ImplSDLGPU3_RenderState struct. (#8866, #8163, #7998, #7988)
 
 Other Changes:
 
@@ -95,6 +98,8 @@ Other Changes:
   to facilitate multiple init/shutdown cycles in same process. (#8792) [@tim-rex]
 - Backends: OpenGL2, OpenGL3: set GL_UNPACK_ALIGNMENT to 1 before updating 
   textures. (#8802) [@Daandelange]
+- Backends: SDL_GPU3: expose current SDL_GPUSampler* in the ImGui_ImplSDLGPU3_RenderState
+  struct. (#8866, #8163, #7998, #7988)
 - Backends: Vulkan: Fixed texture update corruption introduced in 1.92.0,
   affecting some drivers/setups. (#8801, #8755, #8840) [@Retro52, @Miolith]
 - Backends: Vulkan: Avoid calling vkCmdBindDescriptorSets() when texture

imgui.cpp

@@ -392,6 +392,7 @@ IMPLEMENTING SUPPORT for ImGuiBackendFlags_RendererHasTextures:
  When you are not sure about an old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2025/08/08 (1.92.2) - Backends: SDL_GPU3: Changed ImTextureID type from SDL_GPUTextureSamplerBinding* to SDL_GPUTexture*, which is more natural and easier for user to manage. If you need to change the current sampler, you can access the ImGui_ImplSDLGPU3_RenderState struct. (#8866, #8163, #7998, #7988)
  - 2025/07/31 (1.92.2) - Tabs: Renamed ImGuiTabBarFlags_FittingPolicyResizeDown to ImGuiTabBarFlags_FittingPolicyShrink. Kept inline redirection enum (will obsolete).
  - 2025/06/25 (1.92.0) - Layout: commented out legacy ErrorCheckUsingSetCursorPosToExtendParentBoundaries() fallback obsoleted in 1.89 (August 2022) which allowed a SetCursorPos()/SetCursorScreenPos() call WITHOUT AN ITEM
                          to extend parent window/cell boundaries. Replaced with assert/tooltip that would already happens if previously using IMGUI_DISABLE_OBSOLETE_FUNCTIONS. (#5548, #4510, #3355, #1760, #1490, #4152, #150)

imgui.h

@@ -29,7 +29,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM >= 12345')
 #define IMGUI_VERSION       "1.92.2 WIP"
-#define IMGUI_VERSION_NUM   19213
+#define IMGUI_VERSION_NUM   19214
 #define IMGUI_HAS_TABLE             // Added BeginTable() - from IMGUI_VERSION_NUM >= 18000
 #define IMGUI_HAS_TEXTURES          // Added ImGuiBackendFlags_RendererHasTextures - from IMGUI_VERSION_NUM >= 19198