Prepare for SDL3 support

app/SDL_compat.h

@@ -0,0 +1,67 @@
+//
+// Compatibility header for older version of SDL.
+// Include this instead of SDL.h directly.
+//
+
+#pragma once
+
+#include <SDL.h>
+
+// SDL_FRect wasn't added until 2.0.10
+#if !SDL_VERSION_ATLEAST(2, 0, 10)
+typedef struct SDL_FRect
+{
+    float x;
+    float y;
+    float w;
+    float h;
+} SDL_FRect;
+#endif
+
+#ifndef SDL_HINT_VIDEO_X11_FORCE_EGL
+#define SDL_HINT_VIDEO_X11_FORCE_EGL "SDL_VIDEO_X11_FORCE_EGL"
+#endif
+
+#ifndef SDL_HINT_KMSDRM_REQUIRE_DRM_MASTER
+#define SDL_HINT_KMSDRM_REQUIRE_DRM_MASTER "SDL_KMSDRM_REQUIRE_DRM_MASTER"
+#endif
+
+#ifndef SDL_HINT_ALLOW_ALT_TAB_WHILE_GRABBED
+#define SDL_HINT_ALLOW_ALT_TAB_WHILE_GRABBED "SDL_ALLOW_ALT_TAB_WHILE_GRABBED"
+#endif
+
+#ifndef SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE
+#define SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE "SDL_JOYSTICK_HIDAPI_PS4_RUMBLE"
+#endif
+
+#ifndef SDL_HINT_JOYSTICK_HIDAPI_PS5_RUMBLE
+#define SDL_HINT_JOYSTICK_HIDAPI_PS5_RUMBLE "SDL_JOYSTICK_HIDAPI_PS5_RUMBLE"
+#endif
+
+#ifndef SDL_HINT_WINDOWS_USE_D3D9EX
+#define SDL_HINT_WINDOWS_USE_D3D9EX "SDL_WINDOWS_USE_D3D9EX"
+#endif
+
+#ifndef SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS
+#define SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS "SDL_GAMECONTROLLER_USE_BUTTON_LABELS"
+#endif
+
+#ifndef SDL_HINT_MOUSE_RELATIVE_SCALING
+#define SDL_HINT_MOUSE_RELATIVE_SCALING "SDL_MOUSE_RELATIVE_SCALING"
+#endif
+
+#ifndef SDL_HINT_AUDIO_DEVICE_APP_NAME
+#define SDL_HINT_AUDIO_DEVICE_APP_NAME "SDL_AUDIO_DEVICE_APP_NAME"
+#endif
+
+#ifndef SDL_HINT_APP_NAME
+#define SDL_HINT_APP_NAME "SDL_APP_NAME"
+#endif
+
+#ifndef SDL_HINT_MOUSE_AUTO_CAPTURE
+#define SDL_HINT_MOUSE_AUTO_CAPTURE "SDL_MOUSE_AUTO_CAPTURE"
+#endif
+
+#ifndef SDL_HINT_VIDEO_WAYLAND_EMULATE_MOUSE_WARP
+#define SDL_HINT_VIDEO_WAYLAND_EMULATE_MOUSE_WARP "SDL_VIDEO_WAYLAND_EMULATE_MOUSE_WARP"
+#endif