Examples: SDL3: specify SDL_WINDOW_HIGH_PIXEL_DENSITY and make centering consistent + call SDL_RenderScale().

examples/example_sdl3_opengl3/main.cpp

@@ -68,14 +68,13 @@ int main(int, char**)
     SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
     SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
     SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
-    Uint32 window_flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN;
+    SDL_WindowFlags window_flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN | SDL_WINDOW_HIGH_PIXEL_DENSITY;
     SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+OpenGL3 example", 1280, 720, window_flags);
     if (window == nullptr)
     {
         printf("Error: SDL_CreateWindow(): %s\n", SDL_GetError());
         return -1;
     }
-    SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
     if (gl_context == nullptr)
     {
@@ -85,6 +84,7 @@ int main(int, char**)
 
     SDL_GL_MakeCurrent(window, gl_context);
     SDL_GL_SetSwapInterval(1); // Enable vsync
+    SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
     SDL_ShowWindow(window);
 
     // Setup Dear ImGui context

examples/example_sdl3_sdlgpu3/main.cpp

@@ -34,12 +34,15 @@ int main(int, char**)
     }
 
     // Create SDL window graphics context
-    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+SDL_GPU example", 1280, 720, SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY);
+    SDL_WindowFlags window_flags = SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN | SDL_WINDOW_HIGH_PIXEL_DENSITY;
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+SDL_GPU example", 1280, 720, window_flags);
     if (window == nullptr)
     {
         printf("Error: SDL_CreateWindow(): %s\n", SDL_GetError());
         return -1;
     }
+    SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
+    SDL_ShowWindow(window);
 
     // Create GPU Device
     SDL_GPUDevice* gpu_device = SDL_CreateGPUDevice(SDL_GPU_SHADERFORMAT_SPIRV | SDL_GPU_SHADERFORMAT_DXIL | SDL_GPU_SHADERFORMAT_METALLIB,true,nullptr);

examples/example_sdl3_sdlrenderer3/main.cpp

@@ -32,7 +32,7 @@ int main(int, char**)
     }
 
     // Create window with SDL_Renderer graphics context
-    Uint32 window_flags = SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN;
+    SDL_WindowFlags window_flags = SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN | SDL_WINDOW_HIGH_PIXEL_DENSITY;
     SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+SDL_Renderer example", 1280, 720, window_flags);
     if (window == nullptr)
     {
@@ -164,7 +164,7 @@ int main(int, char**)
 
         // Rendering
         ImGui::Render();
-        //SDL_RenderSetScale(renderer, io.DisplayFramebufferScale.x, io.DisplayFramebufferScale.y);
+        SDL_SetRenderScale(renderer, io.DisplayFramebufferScale.x, io.DisplayFramebufferScale.y);
         SDL_SetRenderDrawColorFloat(renderer, clear_color.x, clear_color.y, clear_color.z, clear_color.w);
         SDL_RenderClear(renderer);
         ImGui_ImplSDLRenderer3_RenderDrawData(ImGui::GetDrawData(), renderer);

examples/example_sdl3_vulkan/main.cpp

@@ -353,7 +353,7 @@ int main(int, char**)
     }
 
     // Create window with Vulkan graphics context
-    SDL_WindowFlags window_flags = (SDL_WindowFlags)(SDL_WINDOW_VULKAN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY | SDL_WINDOW_HIDDEN);
+    SDL_WindowFlags window_flags = SDL_WINDOW_VULKAN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN | SDL_WINDOW_HIGH_PIXEL_DENSITY;
     SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+Vulkan example", 1280, 720, window_flags);
     if (window == nullptr)
     {