From 8d3e37eb5343d4a5aa15718ea0a1889c6e4f2d6c Mon Sep 17 00:00:00 2001 From: ocornut Date: Thu, 17 Sep 2026 14:32:33 +0200 Subject: [PATCH] Backends: SDLRenderer3: restore modified texture scale modes at the end of RenderDrawData(). (#9378, #9543) --- backends/imgui_impl_sdlrenderer3.cpp | 59 ++++++++++++++++++++++------ backends/imgui_impl_sdlrenderer3.h | 2 +- docs/CHANGELOG.txt | 3 +- 3 files changed, 51 insertions(+), 13 deletions(-) diff --git a/backends/imgui_impl_sdlrenderer3.cpp b/backends/imgui_impl_sdlrenderer3.cpp index 1a287efa6..3db26573c 100644 --- a/backends/imgui_impl_sdlrenderer3.cpp +++ b/backends/imgui_impl_sdlrenderer3.cpp @@ -25,6 +25,7 @@ // CHANGELOG // (minor and older changes stripped away, please see git history for details) +// 2026-09-17: Restore modified texture scale modes at the end of RenderDrawData(). Added CurrentScaleMode in ImGui_ImplSDLRenderer3_RenderState (#9543, #9378) // 2026-07-15: Fixed default sampler state to be linear (broken 2026-04-23). (#9470, #9378) // 2026-04-23: Added support for standard draw callbacks (in platform_io): DrawCallback_ResetRenderState, DrawCallback_SetSamplerLinear, DrawCallback_SetSamplerNearest. (#9378) // 2026-03-12: Fixed invalid assert in ImGui_ImplSDLRenderer3_UpdateTexture() if ImTextureID_Invalid is defined to be != 0, which became the default since 2026-03-12. (#9295) @@ -58,10 +59,17 @@ #endif // SDL_Renderer data +struct ImGui_ImplSDLRenderer3_TexScaleModeEntry +{ + SDL_Texture* Texture; + SDL_ScaleMode ScaleModeBackup; +}; + struct ImGui_ImplSDLRenderer3_Data { SDL_Renderer* Renderer; // Main viewport's renderer ImVector ColorBuffer; + ImVector TexScaleModeBackups; // Backup of texture scale modes ImGui_ImplSDLRenderer3_Data() { memset((void*)this, 0, sizeof(*this)); } }; @@ -82,7 +90,6 @@ static void ImGui_ImplSDLRenderer3_SetupRenderState(SDL_Renderer* renderer) // FIXME: Technically speaking there are lots of other things we could backup/setup/restore during our render process. SDL_SetRenderViewport(renderer, nullptr); SDL_SetRenderClipRect(renderer, nullptr); - render_state->CurrentScaleMode = SDL_SCALEMODE_LINEAR; } @@ -116,6 +123,38 @@ static void ImGui_ImplSDLRenderer3_DrawCallback_ResetRenderState(const ImDrawLis static void ImGui_ImplSDLRenderer3_DrawCallback_SetSamplerLinear(const ImDrawList*, const ImDrawCmd*) { ImGui_ImplSDLRenderer3_RenderState* render_state = ImGui_ImplSDLRenderer3_GetRenderState(); render_state->CurrentScaleMode = SDL_SCALEMODE_LINEAR; } static void ImGui_ImplSDLRenderer3_DrawCallback_SetSamplerNearest(const ImDrawList*, const ImDrawCmd*) { ImGui_ImplSDLRenderer3_RenderState* render_state = ImGui_ImplSDLRenderer3_GetRenderState(); render_state->CurrentScaleMode = SDL_SCALEMODE_NEAREST; } +// SDLRenderer has various design issues which makes it hard to do it compared to regular graphics API. +// - scale/filtering mode is tied to a texture. +// - scale/filtering mode is not queued as part of the SDL_RenderGeometryXXX commands, so a change in one texture requires a flush. +static void ImGui_ImplSDLRenderer3_TexScaleModeUpdate(SDL_Renderer* renderer, SDL_Texture* tex, SDL_ScaleMode desired_scale_mode) +{ + ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); + SDL_ScaleMode tex_scale_mode = desired_scale_mode; + if (!SDL_GetTextureScaleMode(tex, &tex_scale_mode) || tex_scale_mode == desired_scale_mode) + return; + SDL_FlushRenderer(renderer); + SDL_SetTextureScaleMode(tex, desired_scale_mode); + + // Store backup of old scale mode + for (ImGui_ImplSDLRenderer3_TexScaleModeEntry& entry : bd->TexScaleModeBackups) + if (entry.Texture == tex) + return; + ImGui_ImplSDLRenderer3_TexScaleModeEntry entry = { tex, tex_scale_mode }; + bd->TexScaleModeBackups.push_back(entry); +} + +static void ImGui_ImplSDLRenderer3_TexScaleModeRestoreBackups(SDL_Renderer* renderer) +{ + ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); + if (bd->TexScaleModeBackups.Size == 0) + return; + SDL_FlushRenderer(renderer); + for (ImGui_ImplSDLRenderer3_TexScaleModeEntry& entry : bd->TexScaleModeBackups) + if (entry.ScaleModeBackup != SDL_SCALEMODE_INVALID) + SDL_SetTextureScaleMode(entry.Texture, entry.ScaleModeBackup); + bd->TexScaleModeBackups.resize(0); +} + void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* renderer) { ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData(); @@ -165,11 +204,11 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* // Setup desired state ImGui_ImplSDLRenderer3_SetupRenderState(renderer); + IM_ASSERT(bd->TexScaleModeBackups.Size == 0); // Will project scissor/clipping rectangles into framebuffer space ImVec2 clip_off = draw_data->DisplayPos; // (0,0) unless using multi-viewports ImVec2 clip_scale = render_scale; - SDL_ScaleMode last_scale_mode = render_state.CurrentScaleMode; // Render command lists for (const ImDrawList* draw_list : draw_data->CmdLists) @@ -199,20 +238,17 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* if (clip_max.y > (float)fb_height) { clip_max.y = (float)fb_height; } if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y) continue; - SDL_Rect r = { (int)(clip_min.x), (int)(clip_min.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y) }; SDL_SetRenderClipRect(renderer, &r); + // Setup texture scale/filtering mode + SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID(); + ImGui_ImplSDLRenderer3_TexScaleModeUpdate(renderer, tex, render_state.CurrentScaleMode); + + // Draw const float* xy = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + offsetof(ImDrawVert, pos)); const float* uv = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + offsetof(ImDrawVert, uv)); - const SDL_Color* color = (const SDL_Color*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + offsetof(ImDrawVert, col)); // SDL 2.0.19+ - - if (last_scale_mode != render_state.CurrentScaleMode) - SDL_FlushRenderer(renderer); - - // Bind texture, Draw - SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID(); - SDL_SetTextureScaleMode(tex, render_state.CurrentScaleMode); + const SDL_Color* color = (const SDL_Color*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + offsetof(ImDrawVert, col)); SDL_RenderGeometryRaw8BitColor(renderer, bd->ColorBuffer, tex, xy, (int)sizeof(ImDrawVert), color, (int)sizeof(ImDrawVert), @@ -227,6 +263,7 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* // Restore modified SDL_Renderer state SDL_SetRenderViewport(renderer, old.ViewportEnabled ? &old.Viewport : nullptr); SDL_SetRenderClipRect(renderer, old.ClipEnabled ? &old.ClipRect : nullptr); + ImGui_ImplSDLRenderer3_TexScaleModeRestoreBackups(renderer); } void ImGui_ImplSDLRenderer3_UpdateTexture(ImTextureData* tex) diff --git a/backends/imgui_impl_sdlrenderer3.h b/backends/imgui_impl_sdlrenderer3.h index e4d483ab8..5559a5035 100644 --- a/backends/imgui_impl_sdlrenderer3.h +++ b/backends/imgui_impl_sdlrenderer3.h @@ -49,7 +49,7 @@ IMGUI_IMPL_API void ImGui_ImplSDLRenderer3_UpdateTexture(ImTextureData* tex) struct ImGui_ImplSDLRenderer3_RenderState { SDL_Renderer* Renderer; - SDL_ScaleMode CurrentScaleMode; + SDL_ScaleMode CurrentScaleMode; // Current scale mode during render. }; static inline ImGui_ImplSDLRenderer3_RenderState* ImGui_ImplSDLRenderer3_GetRenderState() { return (ImGui_ImplSDLRenderer3_RenderState*)ImGui::GetPlatformIO().Renderer_RenderState; } diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt index ce018600d..6ba8bcfdd 100644 --- a/docs/CHANGELOG.txt +++ b/docs/CHANGELOG.txt @@ -93,7 +93,7 @@ Other Changes: and various operators. - IO: restore default clipboard/ime/shell platform handlers on ClearPlatformHandlers(), fixing issues switching backends mid-session to one relying on default. (#9537, #8945, #2769) [@lstalmir] -- ImDrawList: +- DrawList: - Per-viewport FramebufferScale for Apple/Retina screen is applied to draw lists: - AA Fringe is scaled accordingly. - Circle and Curves tessellation error are scaled accordingly. @@ -106,6 +106,7 @@ Other Changes: - QNX: added QNX Screen backend. (#9492) [@mgorchak-blackberry] - SDL2: fixed querying framebuffer scale/density when using Metal without going through a SDL_Renderer. (#5592) [@lailoken] + - SDLRenderer3: restore any temporarily modified texture scale modes at the of `RenderDrawData()`. (#9378) - SDLRenderer3: expose CurrentScaleMode in ImGui_ImplSDLRenderer3_RenderState. (#9543, #9378) [@Clownacy] - Vulkan: added for support for multiple Vulkan contexts with custom loaders. (#6616) [@lstalmir] - WebGPU: fixed passing non-integer sizes to `wgpuRenderPassEncoderSetViewport()`