GPU: Add swapchain dimension out params (#11003)

include/SDL3/SDL_gpu.h

@@ -3316,7 +3316,7 @@ extern SDL_DECLSPEC void SDLCALL SDL_ReleaseWindowFromGPUDevice(
  * \param window an SDL_Window that has been claimed.
  * \param swapchain_composition the desired composition of the swapchain.
  * \param present_mode the desired present mode for the swapchain.
- * \returns true if successful, false on error.
+ * \returns true if successful, false on error; call SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
@@ -3350,20 +3350,22 @@ extern SDL_DECLSPEC SDL_GPUTextureFormat SDLCALL SDL_GetGPUSwapchainTextureForma
  * When a swapchain texture is acquired on a command buffer, it will
  * automatically be submitted for presentation when the command buffer is
  * submitted. The swapchain texture should only be referenced by the command
- * buffer used to acquire it. The swapchain texture handle can be NULL under
+ * buffer used to acquire it. The swapchain texture handle can be filled in with NULL under
  * certain conditions. This is not necessarily an error. If this function
- * returns false then there is an error. The swapchain texture is managed by
- * the implementation and must not be freed by the user. The texture
- * dimensions will be the width and height of the claimed window. You can
- * obtain these dimensions by calling SDL_GetWindowSizeInPixels. You MUST NOT
+ * returns false then there is an error.
+ *
+ * The swapchain texture is managed by
+ * the implementation and must not be freed by the user. You MUST NOT
  * call this function from any thread other than the one that created the
  * window.
  *
  * \param command_buffer a command buffer.
  * \param window a window that has been claimed.
- * \param swapchainTexture a pointer filled in with a swapchain texture
+ * \param swapchain_texture a pointer filled in with a swapchain texture
  *                         handle.
- * \returns true on success, false on error.
+ * \param swapchain_texture_width a pointer filled in with the swapchain texture width, may be NULL.
+ * \param swapchain_texture_height a pointer filled in with the swapchain texture height, may be NULL.
+ * \returns true on success, false on error; call SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
@@ -3375,7 +3377,9 @@ extern SDL_DECLSPEC SDL_GPUTextureFormat SDLCALL SDL_GetGPUSwapchainTextureForma
 extern SDL_DECLSPEC bool SDLCALL SDL_AcquireGPUSwapchainTexture(
     SDL_GPUCommandBuffer *command_buffer,
     SDL_Window *window,
-    SDL_GPUTexture **swapchainTexture);
+    SDL_GPUTexture **swapchain_texture,
+    Uint32 *swapchain_texture_width,
+    Uint32 *swapchain_texture_height);
 
 /**
  * Submits a command buffer so its commands can be processed on the GPU.

src/dynapi/SDL_dynapi_procs.h

@@ -50,7 +50,7 @@ SDL_DYNAPI_PROC(int,SDL_swprintf,(SDL_OUT_Z_CAP(b) wchar_t *a, size_t b, SDL_PRI
 // New API symbols are added at the end
 SDL_DYNAPI_PROC(SDL_Surface*,SDL_AcquireCameraFrame,(SDL_Camera *a, Uint64 *b),(a,b),return)
 SDL_DYNAPI_PROC(SDL_GPUCommandBuffer*,SDL_AcquireGPUCommandBuffer,(SDL_GPUDevice *a),(a),return)
-SDL_DYNAPI_PROC(bool,SDL_AcquireGPUSwapchainTexture,(SDL_GPUCommandBuffer *a, SDL_Window *b, SDL_GPUTexture **c),(a,b,c),return)
+SDL_DYNAPI_PROC(bool,SDL_AcquireGPUSwapchainTexture,(SDL_GPUCommandBuffer *a, SDL_Window *b, SDL_GPUTexture **c, Uint32 *d, Uint32 *e),(a,b,c,d,e),return)
 SDL_DYNAPI_PROC(int,SDL_AddAtomicInt,(SDL_AtomicInt *a, int b),(a,b),return)
 SDL_DYNAPI_PROC(bool,SDL_AddEventWatch,(SDL_EventFilter a, void *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_AddGamepadMapping,(const char *a),(a),return)

src/gpu/SDL_gpu.c

@@ -2613,7 +2613,9 @@ SDL_GPUTextureFormat SDL_GetGPUSwapchainTextureFormat(
 bool SDL_AcquireGPUSwapchainTexture(
     SDL_GPUCommandBuffer *command_buffer,
     SDL_Window *window,
-    SDL_GPUTexture **swapchainTexture)
+    SDL_GPUTexture **swapchain_texture,
+    Uint32 *swapchain_texture_width,
+    Uint32 *swapchain_texture_height)
 {
     if (command_buffer == NULL) {
         SDL_InvalidParamError("command_buffer");
@@ -2623,8 +2625,8 @@ bool SDL_AcquireGPUSwapchainTexture(
         SDL_InvalidParamError("window");
         return false;
     }
-    if (swapchainTexture == NULL) {
-        SDL_InvalidParamError("swapchainTexture");
+    if (swapchain_texture == NULL) {
+        SDL_InvalidParamError("swapchain_texture");
         return false;
     }
 
@@ -2636,7 +2638,9 @@ bool SDL_AcquireGPUSwapchainTexture(
     return COMMAND_BUFFER_DEVICE->AcquireSwapchainTexture(
         command_buffer,
         window,
-        swapchainTexture);
+        swapchain_texture,
+        swapchain_texture_width,
+        swapchain_texture_height);
 }
 
 bool SDL_SubmitGPUCommandBuffer(

src/gpu/SDL_sysgpu.h

@@ -651,7 +651,9 @@ struct SDL_GPUDevice
     bool (*AcquireSwapchainTexture)(
         SDL_GPUCommandBuffer *commandBuffer,
         SDL_Window *window,
-        SDL_GPUTexture **swapchainTexture);
+        SDL_GPUTexture **swapchainTexture,
+        Uint32 *swapchainTextureWidth,
+        Uint32 *swapchainTextureHeight);
 
     bool (*Submit)(
         SDL_GPUCommandBuffer *commandBuffer);

src/gpu/d3d11/SDL_gpu_d3d11.c

@@ -480,6 +480,8 @@ typedef struct D3D11WindowData
     SDL_GPUSwapchainComposition swapchainComposition;
     DXGI_FORMAT swapchainFormat;
     DXGI_COLOR_SPACE_TYPE swapchainColorSpace;
+    Uint32 width;
+    Uint32 height;
     SDL_GPUFence *inFlightFences[MAX_FRAMES_IN_FLIGHT];
     Uint32 frameCounter;
     bool needsSwapchainRecreate;
@@ -5250,6 +5252,8 @@ static bool D3D11_INTERNAL_CreateSwapchain(
     windowData->texture.container = &windowData->textureContainer;
     windowData->texture.containerIndex = 0;
 
+    windowData->width = w;
+    windowData->height = h;
     return true;
 }
 
@@ -5288,6 +5292,8 @@ static bool D3D11_INTERNAL_ResizeSwapchain(
 
     windowData->textureContainer.header.info.width = w;
     windowData->textureContainer.header.info.height = h;
+    windowData->width = w;
+    windowData->height = h;
     windowData->needsSwapchainRecreate = !result;
     return result;
 }
@@ -5469,7 +5475,9 @@ static void D3D11_ReleaseWindow(
 static bool D3D11_AcquireSwapchainTexture(
     SDL_GPUCommandBuffer *commandBuffer,
     SDL_Window *window,
-    SDL_GPUTexture **swapchainTexture)
+    SDL_GPUTexture **swapchainTexture,
+    Uint32 *swapchainTextureWidth,
+    Uint32 *swapchainTextureHeight)
 {
     D3D11CommandBuffer *d3d11CommandBuffer = (D3D11CommandBuffer *)commandBuffer;
     D3D11Renderer *renderer = (D3D11Renderer *)d3d11CommandBuffer->renderer;
@@ -5477,6 +5485,12 @@ static bool D3D11_AcquireSwapchainTexture(
     HRESULT res;
 
     *swapchainTexture = NULL;
+    if (swapchainTextureWidth) {
+        *swapchainTextureWidth = 0;
+    }
+    if (swapchainTextureHeight) {
+        *swapchainTextureHeight = 0;
+    }
 
     windowData = D3D11_INTERNAL_FetchWindowData(window);
     if (windowData == NULL) {
@@ -5489,6 +5503,13 @@ static bool D3D11_AcquireSwapchainTexture(
         }
     }
 
+    if (swapchainTextureWidth) {
+        *swapchainTextureWidth = windowData->width;
+    }
+    if (swapchainTextureHeight) {
+        *swapchainTextureHeight = windowData->height;
+    }
+
     if (windowData->inFlightFences[windowData->frameCounter] != NULL) {
         if (windowData->presentMode == SDL_GPU_PRESENTMODE_VSYNC) {
             // In VSYNC mode, block until the least recent presented frame is done

src/gpu/d3d12/SDL_gpu_d3d12.c

@@ -554,6 +554,8 @@ typedef struct D3D12WindowData
 
     D3D12TextureContainer textureContainers[MAX_FRAMES_IN_FLIGHT];
     SDL_GPUFence *inFlightFences[MAX_FRAMES_IN_FLIGHT];
+    Uint32 width;
+    Uint32 height;
     bool needsSwapchainRecreate;
 } D3D12WindowData;
 
@@ -6331,6 +6333,8 @@ static bool D3D12_INTERNAL_ResizeSwapchain(
         }
     }
 
+    windowData->width = w;
+    windowData->height = h;
     windowData->needsSwapchainRecreate = false;
     return true;
 }
@@ -6382,6 +6386,9 @@ static bool D3D12_INTERNAL_CreateSwapchain(
 
     swapchainFormat = SwapchainCompositionToTextureFormat[swapchainComposition];
 
+    int w, h;
+    SDL_GetWindowSizeInPixels(windowData->window, &w, &h);
+
     // Initialize the swapchain buffer descriptor
     swapchainDesc.Width = 0;
     swapchainDesc.Height = 0;
@@ -6477,6 +6484,8 @@ static bool D3D12_INTERNAL_CreateSwapchain(
     windowData->swapchainComposition = swapchainComposition;
     windowData->swapchainColorSpace = SwapchainCompositionToColorSpace[swapchainComposition];
     windowData->frameCounter = 0;
+    windowData->width = w;
+    windowData->height = h;
 
     // Precache blit pipelines for the swapchain format
     for (Uint32 i = 0; i < 5; i += 1) {
@@ -6907,7 +6916,9 @@ static SDL_GPUCommandBuffer *D3D12_AcquireCommandBuffer(
 static bool D3D12_AcquireSwapchainTexture(
     SDL_GPUCommandBuffer *commandBuffer,
     SDL_Window *window,
-    SDL_GPUTexture **swapchainTexture)
+    SDL_GPUTexture **swapchainTexture,
+    Uint32 *swapchainTextureWidth,
+    Uint32 *swapchainTextureHeight)
 {
     D3D12CommandBuffer *d3d12CommandBuffer = (D3D12CommandBuffer *)commandBuffer;
     D3D12Renderer *renderer = d3d12CommandBuffer->renderer;
@@ -6916,6 +6927,12 @@ static bool D3D12_AcquireSwapchainTexture(
     HRESULT res;
 
     *swapchainTexture = NULL;
+    if (swapchainTextureWidth) {
+        *swapchainTextureWidth = 0;
+    }
+    if (swapchainTextureHeight) {
+        *swapchainTextureHeight = 0;
+    }
 
     windowData = D3D12_INTERNAL_FetchWindowData(window);
     if (windowData == NULL) {
@@ -6928,6 +6945,13 @@ static bool D3D12_AcquireSwapchainTexture(
         }
     }
 
+    if (swapchainTextureWidth) {
+        *swapchainTextureWidth = windowData->width;
+    }
+    if (swapchainTextureHeight) {
+        *swapchainTextureHeight = windowData->height;
+    }
+
     if (windowData->inFlightFences[windowData->frameCounter] != NULL) {
         if (windowData->present_mode == SDL_GPU_PRESENTMODE_VSYNC) {
             // In VSYNC mode, block until the least recent presented frame is done

src/gpu/metal/SDL_gpu_metal.m

@@ -3590,7 +3590,9 @@ static void METAL_ReleaseWindow(
 static bool METAL_AcquireSwapchainTexture(
     SDL_GPUCommandBuffer *commandBuffer,
     SDL_Window *window,
-    SDL_GPUTexture **texture)
+    SDL_GPUTexture **texture,
+    Uint32 *swapchainTextureWidth,
+    Uint32 *swapchainTextureHeight)
 {
     @autoreleasepool {
         MetalCommandBuffer *metalCommandBuffer = (MetalCommandBuffer *)commandBuffer;
@@ -3599,6 +3601,12 @@ static bool METAL_AcquireSwapchainTexture(
         CGSize drawableSize;
 
         *texture = NULL;
+        if (swapchainTextureWidth) {
+            *swapchainTextureWidth = 0;
+        }
+        if (swapchainTextureHeight) {
+            *swapchainTextureHeight = 0;
+        }
 
         windowData = METAL_INTERNAL_FetchWindowData(window);
         if (windowData == NULL) {
@@ -3613,6 +3621,12 @@ static bool METAL_AcquireSwapchainTexture(
         drawableSize = windowData->layer.drawableSize;
         windowData->textureContainer.header.info.width = (Uint32)drawableSize.width;
         windowData->textureContainer.header.info.height = (Uint32)drawableSize.height;
+        if (swapchainTextureWidth) {
+            *swapchainTextureWidth = (Uint32)drawableSize.width;
+        }
+        if (swapchainTextureHeight) {
+            *swapchainTextureHeight = (Uint32)drawableSize.height;
+        }
 
         // Set up presentation
         if (metalCommandBuffer->windowDataCount == metalCommandBuffer->windowDataCapacity) {

src/render/gpu/SDL_render_gpu.c

@@ -957,7 +957,8 @@ static bool GPU_RenderPresent(SDL_Renderer *renderer)
     GPU_RenderData *data = (GPU_RenderData *)renderer->internal;
 
     SDL_GPUTexture *swapchain;
-    bool result = SDL_AcquireGPUSwapchainTexture(data->state.command_buffer, renderer->window, &swapchain);
+    Uint32 swapchain_texture_width, swapchain_texture_height;
+    bool result = SDL_AcquireGPUSwapchainTexture(data->state.command_buffer, renderer->window, &swapchain, &swapchain_texture_width, &swapchain_texture_height);
 
     if (!result) {
         SDL_LogError(SDL_LOG_CATEGORY_RENDER, "Failed to acquire swapchain texture: %s", SDL_GetError());
@@ -967,8 +968,6 @@ static bool GPU_RenderPresent(SDL_Renderer *renderer)
         goto submit;
     }
 
-    SDL_GPUTextureFormat swapchain_fmt = SDL_GetGPUSwapchainTextureFormat(data->device, renderer->window);
-
     SDL_GPUBlitInfo blit_info;
     SDL_zero(blit_info);
 
@@ -976,18 +975,13 @@ static bool GPU_RenderPresent(SDL_Renderer *renderer)
     blit_info.source.w = data->backbuffer.width;
     blit_info.source.h = data->backbuffer.height;
     blit_info.destination.texture = swapchain;
-    blit_info.destination.w = renderer->output_pixel_w;
-    blit_info.destination.h = renderer->output_pixel_h;
+    blit_info.destination.w = swapchain_texture_width;
+    blit_info.destination.h = swapchain_texture_height;
     blit_info.load_op = SDL_GPU_LOADOP_DONT_CARE;
     blit_info.filter = SDL_GPU_FILTER_LINEAR;
 
     SDL_BlitGPUTexture(data->state.command_buffer, &blit_info);
 
-    if (renderer->output_pixel_w != data->backbuffer.width || renderer->output_pixel_h != data->backbuffer.height || swapchain_fmt != data->backbuffer.format) {
-        SDL_ReleaseGPUTexture(data->device, data->backbuffer.texture);
-        CreateBackbuffer(data, renderer->output_pixel_w, renderer->output_pixel_h, swapchain_fmt);
-    }
-
 // *** FIXME ***
 // This is going to block if there is ever a frame in flight.
 // We should do something similar to FNA3D
@@ -1006,6 +1000,11 @@ submit:
     SDL_SubmitGPUCommandBuffer(data->state.command_buffer);
 #endif
 
+    if (swapchain != NULL && (swapchain_texture_width != data->backbuffer.width || swapchain_texture_height != data->backbuffer.height)) {
+        SDL_ReleaseGPUTexture(data->device, data->backbuffer.texture);
+        CreateBackbuffer(data, swapchain_texture_width, swapchain_texture_height, SDL_GetGPUSwapchainTextureFormat(data->device, renderer->window));
+    }
+
     data->state.command_buffer = SDL_AcquireGPUCommandBuffer(data->device);
 
     return true;

test/testgpu_simple_clear.c

@@ -82,7 +82,7 @@ SDL_AppResult SDL_AppIterate(void *appstate)
 	}
 
     SDL_GPUTexture *swapchainTexture;
-	if (!SDL_AcquireGPUSwapchainTexture(cmdbuf, state->windows[0], &swapchainTexture)) {
+	if (!SDL_AcquireGPUSwapchainTexture(cmdbuf, state->windows[0], &swapchainTexture, NULL, NULL)) {
         SDL_Log("SDL_AcquireGPUSwapchainTexture failed: %s", SDL_GetError());
         return SDL_APP_FAILURE;
     }

test/testgpu_spinning_cube.c

@@ -333,7 +333,7 @@ Render(SDL_Window *window, const int windownum)
     SDL_GPURenderPass *pass;
     SDL_GPUBufferBinding vertex_binding;
     SDL_GPUBlitInfo blit_info;
-    int drawablew, drawableh;
+    Uint32 drawablew, drawableh;
 
     /* Acquire the swapchain texture */
 
@@ -342,7 +342,7 @@ Render(SDL_Window *window, const int windownum)
         SDL_Log("Failed to acquire command buffer :%s", SDL_GetError());
         quit(2);
     }
-    if (!SDL_AcquireGPUSwapchainTexture(cmd, state->windows[windownum], &swapchainTexture)) {
+    if (!SDL_AcquireGPUSwapchainTexture(cmd, state->windows[windownum], &swapchainTexture, &drawablew, &drawableh)) {
         SDL_Log("Failed to acquire swapchain texture: %s", SDL_GetError());
         quit(2);
     }
@@ -353,8 +353,6 @@ Render(SDL_Window *window, const int windownum)
         return;
     }
 
-    SDL_GetWindowSizeInPixels(window, &drawablew, &drawableh);
-
     /*
     * Do some rotation with Euler angles. It is not a fixed axis as
     * quaterions would be, but the effect is cool.