Simplify game callbacks.

1 files changed, 34 insertions, 5 deletions

diff --git a/gfx-app/include/gfx/gfx_app.h b/gfx-app/include/gfx/gfx_app.h
index 0033bde..3c544fa 100644
--- a/gfx-app/include/gfx/gfx_app.h
+++ b/gfx-app/include/gfx/gfx_app.h
@@ -2,6 +2,7 @@
 
 #include <stdbool.h>
 
+/// Application settings.
 typedef struct GfxAppDesc {
   int          argc;    // Number of application arguments.
   const char** argv;    // Application arguments.
@@ -12,12 +13,19 @@ typedef struct GfxAppDesc {
   const char*  title;             // Window title.
 } GfxAppDesc;
 
+typedef bool (*GfxAppInit)(const GfxAppDesc*, void** app_state);
+typedef void (*GfxAppUpdate)(void* app_state, double t, double dt);
+typedef void (*GfxAppRender)(void* app_state);
+typedef void (*GfxAppResize)(void* app_state, int width, int height);
+typedef void (*GfxAppShutdown)(void* app_state);
+
+/// Application callback functions.
 typedef struct GfxAppCallbacks {
-  bool (*init)(const GfxAppDesc*, void** app_state);
-  void (*update)(void* app_state, double t, double dt);
-  void (*render)(void* app_state);
-  void (*resize)(void* app_state, int width, int height);
-  void (*shutdown)(void* app_state);
+  GfxAppInit     init;
+  GfxAppUpdate   update;
+  GfxAppRender   render;
+  GfxAppResize   resize;
+  GfxAppShutdown shutdown;
 } GfxAppCallbacks;
 
 /// Create a window with an OpenGL context and run the main loop.
@@ -25,3 +33,24 @@ bool gfx_app_run(const GfxAppDesc*, const GfxAppCallbacks*);
 
 /// Get the mouse coordinates relative to the app's window.
 void gfx_app_get_mouse_position(double* x, double* y);
+
+/// Define a main function that initializes and puts the application in a loop.
+/// See also: gfx_app_run().
+#define GFX_APP_MAIN(WIDTH, HEIGHT, MAX_FPS)                                 \
+  int main(int argc, const char** argv) {                                    \
+    gfx_app_run(                                                             \
+        &(GfxAppDesc){                                                       \
+            .argc              = argc,                                       \
+            .argv              = argv,                                       \
+            .width             = WIDTH,                                      \
+            .height            = HEIGHT,                                     \
+            .max_fps           = MAX_FPS,                                    \
+            .update_delta_time = MAX_FPS > 0 ? 1.0 / (double)MAX_FPS : 0.0}, \
+        &(GfxAppCallbacks){                                                  \
+            .init     = (GfxAppInit)app_init,                                \
+            .update   = (GfxAppUpdate)app_update,                            \
+            .render   = (GfxAppRender)app_render,                            \
+            .resize   = (GfxAppResize)app_resize,                            \
+            .shutdown = (GfxAppShutdown)app_end});                           \
+    return 0;                                                                \
+  }