diff --git a/backends/imgui_impl_sdlrenderer3.cpp b/backends/imgui_impl_sdlrenderer3.cpp index 42fefa0cd..ef6f0441c 100644 --- a/backends/imgui_impl_sdlrenderer3.cpp +++ b/backends/imgui_impl_sdlrenderer3.cpp @@ -10,8 +10,9 @@ // and it might be difficult to step out of those boundaries. // Implemented features: -// [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID! +// [X] Renderer: User texture binding. Use 'SDL_Texture*' as texture identifier. Read the FAQ about ImTextureID/ImTextureRef! // [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset). +// [X] Renderer: Texture updates support for dynamic font system (ImGuiBackendFlags_RendererHasTextures). // [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'. // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. @@ -23,6 +24,7 @@ // - Introduction, links and more at the top of imgui.cpp // CHANGELOG +// 2025-06-11: Added support for ImGuiBackendFlags_RendererHasTextures, for dynamic font atlas. Removed ImGui_ImplSDLRenderer3_CreateFontsTexture() and ImGui_ImplSDLRenderer3_DestroyFontsTexture(). // 2025-01-18: Use endian-dependent RGBA32 texture format, to match SDL_Color. // 2024-10-09: Expose selected render state in ImGui_ImplSDLRenderer3_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks. // 2024-07-01: Update for SDL3 api changes: SDL_RenderGeometryRaw() uint32 version was removed (SDL#9009). @@ -51,7 +53,6 @@ struct ImGui_ImplSDLRenderer3_Data { SDL_Renderer* Renderer; // Main viewport's renderer - SDL_Texture* FontTexture; ImVector ColorBuffer; ImGui_ImplSDLRenderer3_Data() { memset((void*)this, 0, sizeof(*this)); } @@ -77,6 +78,7 @@ bool ImGui_ImplSDLRenderer3_Init(SDL_Renderer* renderer) io.BackendRendererUserData = (void*)bd; io.BackendRendererName = "imgui_impl_sdlrenderer3"; io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. + io.BackendFlags |= ImGuiBackendFlags_RendererHasTextures; // We can honor ImGuiPlatformIO::Textures[] requests during render. bd->Renderer = renderer; @@ -93,7 +95,7 @@ void ImGui_ImplSDLRenderer3_Shutdown() io.BackendRendererName = nullptr; io.BackendRendererUserData = nullptr; - io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset; + io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasTextures); IM_DELETE(bd); } @@ -109,9 +111,7 @@ void ImGui_ImplSDLRenderer3_NewFrame() { ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplSDLRenderer3_Init()?"); - - if (!bd->FontTexture) - ImGui_ImplSDLRenderer3_CreateDeviceObjects(); + IM_UNUSED(bd); } // https://github.com/libsdl-org/SDL/issues/9009 @@ -152,6 +152,13 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* if (fb_width == 0 || fb_height == 0) return; + // Catch up with texture updates. Most of the times, the list will have 1 element with an OK status, aka nothing to do. + // (This almost always points to ImGui::GetPlatformIO().Textures[] but is part of ImDrawData to allow overriding or disabling texture updates). + if (draw_data->Textures != nullptr) + for (ImTextureData* tex : *draw_data->Textures) + if (tex->Status != ImTextureStatus_OK) + ImGui_ImplSDLRenderer3_UpdateTexture(tex); + // Backup SDL_Renderer state that will be modified to restore it afterwards struct BackupSDLRendererState { @@ -235,55 +242,67 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* SDL_SetRenderClipRect(renderer, old.ClipEnabled ? &old.ClipRect : nullptr); } -// Called by Init/NewFrame/Shutdown -bool ImGui_ImplSDLRenderer3_CreateFontsTexture() +void ImGui_ImplSDLRenderer3_UpdateTexture(ImTextureData* tex) { - ImGuiIO& io = ImGui::GetIO(); ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); - // Build texture atlas - unsigned char* pixels; - int width, height; - io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory. - - // Upload texture to graphics system - // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling) - bd->FontTexture = SDL_CreateTexture(bd->Renderer, SDL_PIXELFORMAT_RGBA32, SDL_TEXTUREACCESS_STATIC, width, height); - if (bd->FontTexture == nullptr) + if (tex->Status == ImTextureStatus_WantCreate) { - SDL_Log("error creating texture"); - return false; + // Create and upload new texture to graphics system + //IMGUI_DEBUG_LOG("UpdateTexture #%03d: WantCreate %dx%d\n", tex->UniqueID, tex->Width, tex->Height); + IM_ASSERT(tex->TexID == 0 && tex->BackendUserData == nullptr); + IM_ASSERT(tex->Format == ImTextureFormat_RGBA32); + + // Create texture + // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling) + SDL_Texture* sdl_texture = SDL_CreateTexture(bd->Renderer, SDL_PIXELFORMAT_RGBA32, SDL_TEXTUREACCESS_STATIC, tex->Width, tex->Height); + IM_ASSERT(sdl_texture != nullptr && "Backend failed to create texture!"); + SDL_UpdateTexture(sdl_texture, nullptr, tex->GetPixels(), tex->GetPitch()); + SDL_SetTextureBlendMode(sdl_texture, SDL_BLENDMODE_BLEND); + SDL_SetTextureScaleMode(sdl_texture, SDL_SCALEMODE_LINEAR); + + // Store identifiers + tex->SetTexID((ImTextureID)(intptr_t)sdl_texture); + tex->SetStatus(ImTextureStatus_OK); } - SDL_UpdateTexture(bd->FontTexture, nullptr, pixels, 4 * width); - SDL_SetTextureBlendMode(bd->FontTexture, SDL_BLENDMODE_BLEND); - SDL_SetTextureScaleMode(bd->FontTexture, SDL_SCALEMODE_LINEAR); - - // Store our identifier - io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture); - - return true; -} - -void ImGui_ImplSDLRenderer3_DestroyFontsTexture() -{ - ImGuiIO& io = ImGui::GetIO(); - ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); - if (bd->FontTexture) + else if (tex->Status == ImTextureStatus_WantUpdates) { - io.Fonts->SetTexID(0); - SDL_DestroyTexture(bd->FontTexture); - bd->FontTexture = nullptr; + // Update selected blocks. We only ever write to textures regions which have never been used before! + // This backend choose to use tex->Updates[] but you can use tex->UpdateRect to upload a single region. + SDL_Texture* sdl_texture = (SDL_Texture*)(intptr_t)tex->TexID; + for (ImTextureRect& r : tex->Updates) + { + SDL_Rect sdl_r = { r.x, r.y, r.w, r.h }; + SDL_UpdateTexture(sdl_texture, &sdl_r, tex->GetPixelsAt(r.x, r.y), tex->GetPitch()); + } + tex->SetStatus(ImTextureStatus_OK); + } + else if (tex->Status == ImTextureStatus_WantDestroy) + { + SDL_Texture* sdl_texture = (SDL_Texture*)(intptr_t)tex->TexID; + if (sdl_texture == nullptr) + return; + SDL_DestroyTexture(sdl_texture); + + // Clear identifiers and mark as destroyed (in order to allow e.g. calling InvalidateDeviceObjects while running) + tex->SetTexID(ImTextureID_Invalid); + tex->SetStatus(ImTextureStatus_Destroyed); } } -bool ImGui_ImplSDLRenderer3_CreateDeviceObjects() +void ImGui_ImplSDLRenderer3_CreateDeviceObjects() { - return ImGui_ImplSDLRenderer3_CreateFontsTexture(); } void ImGui_ImplSDLRenderer3_DestroyDeviceObjects() { - ImGui_ImplSDLRenderer3_DestroyFontsTexture(); + // Destroy all textures + for (ImTextureData* tex : ImGui::GetPlatformIO().Textures) + if (tex->RefCount == 1) + { + tex->SetStatus(ImTextureStatus_WantDestroy); + ImGui_ImplSDLRenderer3_UpdateTexture(tex); + } } //----------------------------------------------------------------------------- diff --git a/backends/imgui_impl_sdlrenderer3.h b/backends/imgui_impl_sdlrenderer3.h index 3473bcc77..170560fdc 100644 --- a/backends/imgui_impl_sdlrenderer3.h +++ b/backends/imgui_impl_sdlrenderer3.h @@ -10,8 +10,9 @@ // and it might be difficult to step out of those boundaries. // Implemented features: -// [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID! +// [X] Renderer: User texture binding. Use 'SDL_Texture*' as texture identifier. Read the FAQ about ImTextureID/ImTextureRef! // [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset). +// [X] Renderer: Texture updates support for dynamic font system (ImGuiBackendFlags_RendererHasTextures). // [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'. // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. @@ -35,11 +36,12 @@ IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_NewFrame(); IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* renderer); // Called by Init/NewFrame/Shutdown -IMGUI_IMPL_API bool ImGui_ImplSDLRenderer3_CreateFontsTexture(); -IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_DestroyFontsTexture(); -IMGUI_IMPL_API bool ImGui_ImplSDLRenderer3_CreateDeviceObjects(); +IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_CreateDeviceObjects(); IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_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_ImplSDLRenderer3_UpdateTexture(ImTextureData* tex); + // [BETA] Selected render state data shared with callbacks. // This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplSDLRenderer3_RenderDrawData() call. // (Please open an issue if you feel you need access to more data)