Initial Commit

thirdparty/SDL3-3.4.0/examples/save-rendering-to-bitmaps.h

@@ -0,0 +1,49 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/*
+This is for generating thumbnails and videos of examples. Just include it
+temporarily and let it override SDL_RenderPresent, etc, and it'll dump each
+frame rendered to a new .png file.
+*/
+
+static bool SAVERENDERING_SDL_RenderPresent(SDL_Renderer *renderer)
+{
+    static unsigned int framenum = 0;
+    SDL_Surface *surface = SDL_RenderReadPixels(renderer, NULL);
+    if (!surface) {
+        SDL_LogError(SDL_LOG_CATEGORY_RENDER, "Failed to read pixels for frame #%u! (%s)", framenum, SDL_GetError());
+    } else {
+        char fname[64];
+        SDL_snprintf(fname, sizeof (fname), "frame%05u.png", framenum);
+        if (!SDL_SavePNG(surface, fname)) {
+            SDL_LogError(SDL_LOG_CATEGORY_RENDER, "Failed to save png for frame #%u! (%s)", framenum, SDL_GetError());
+        }
+        SDL_DestroySurface(surface);
+    }
+
+    framenum++;
+
+    return SDL_RenderPresent(renderer);
+}
+
+#define SDL_RenderPresent SAVERENDERING_SDL_RenderPresent
+