Added properties for the swap chain in the direct3d11 and direct3d12 renderers

Fixes https://github.com/libsdl-org/SDL/issues/9775

include/SDL3/SDL_render.h

@@ -397,11 +397,13 @@ extern DECLSPEC int SDLCALL SDL_GetRendererInfo(SDL_Renderer *renderer, SDL_Rend
  *
  * - `SDL_PROP_RENDERER_D3D11_DEVICE_POINTER`: the ID3D11Device associated
  *   with the renderer
+ * - `SDL_PROP_RENDERER_D3D11_SWAPCHAIN_POINTER`: the IDXGISwapChain1 associated with the renderer. This may change when the window is resized.
  *
  * With the direct3d12 renderer:
  *
  * - `SDL_PROP_RENDERER_D3D12_DEVICE_POINTER`: the ID3D12Device associated
  *   with the renderer
+ * - `SDL_PROP_RENDERER_D3D12_SWAPCHAIN_POINTER`: the IDXGISwapChain4 associated with the renderer.
  * - `SDL_PROP_RENDERER_D3D12_COMMAND_QUEUE_POINTER`: the ID3D12CommandQueue
  *   associated with the renderer
  *
@@ -443,7 +445,9 @@ extern DECLSPEC SDL_PropertiesID SDLCALL SDL_GetRendererProperties(SDL_Renderer
 #define SDL_PROP_RENDERER_HDR_HEADROOM_FLOAT                        "SDL.renderer.HDR_headroom"
 #define SDL_PROP_RENDERER_D3D9_DEVICE_POINTER                       "SDL.renderer.d3d9.device"
 #define SDL_PROP_RENDERER_D3D11_DEVICE_POINTER                      "SDL.renderer.d3d11.device"
+#define SDL_PROP_RENDERER_D3D11_SWAPCHAIN_POINTER                   "SDL.renderer.d3d11.swap_chain"
 #define SDL_PROP_RENDERER_D3D12_DEVICE_POINTER                      "SDL.renderer.d3d12.device"
+#define SDL_PROP_RENDERER_D3D12_SWAPCHAIN_POINTER                   "SDL.renderer.d3d12.swap_chain"
 #define SDL_PROP_RENDERER_D3D12_COMMAND_QUEUE_POINTER               "SDL.renderer.d3d12.command_queue"
 #define SDL_PROP_RENDERER_VULKAN_INSTANCE_POINTER                   "SDL.renderer.vulkan.instance"
 #define SDL_PROP_RENDERER_VULKAN_SURFACE_NUMBER                     "SDL.renderer.vulkan.surface"

src/render/direct3d11/SDL_render_d3d11.c

@@ -1024,6 +1024,8 @@ static HRESULT D3D11_CreateSwapChain(SDL_Renderer *renderer, int w, int h)
         }
     }
 
+    SDL_SetProperty(SDL_GetRendererProperties(renderer), SDL_PROP_RENDERER_D3D11_SWAPCHAIN_POINTER, data->swapChain);
+
 done:
     SAFE_RELEASE(swapChain3);
     SAFE_RELEASE(coreWindow);
@@ -1612,7 +1614,7 @@ static int D3D11_UpdateTexture(SDL_Renderer *renderer, SDL_Texture *texture,
     if (textureData->nv12) {
         const Uint8 *Yplane = (const Uint8 *)srcPixels;
         const Uint8 *UVplane = Yplane + rect->h * srcPitch;
-        
+
         return D3D11_UpdateTextureNV(renderer, texture, rect, Yplane, srcPitch, UVplane, srcPitch);
 
     } else if (textureData->yuv) {

src/render/direct3d12/SDL_render_d3d12.c

@@ -1318,6 +1318,8 @@ static HRESULT D3D12_CreateSwapChain(SDL_Renderer *renderer, int w, int h)
         result = DXGI_ERROR_UNSUPPORTED;
     }
 
+    SDL_SetProperty(SDL_GetRendererProperties(renderer), SDL_PROP_RENDERER_D3D12_SWAPCHAIN_POINTER, data->swapChain);
+
 done:
     SAFE_RELEASE(swapChain);
     return result;