port: hard cap FPS to 200 for now

port/fast3d/gfx_sdl2.cpp

@@ -291,7 +291,7 @@ static void gfx_sdl_set_target_fps(int fps) {
 }
 
 static bool gfx_sdl_can_disable_vsync(void) {
-    return false;
+    return true;
 }
 
 static void *gfx_sdl_get_window_handle(void) {
@@ -302,9 +302,13 @@ static void gfx_sdl_set_window_title(const char *title) {
     SDL_SetWindowTitle(wnd, title);
 }
 
-static void gfx_sdl_set_swap_interval(int interval) {
-    SDL_GL_SetSwapInterval(interval);
-    vsync_enabled = (interval != 0);
+static bool gfx_sdl_set_swap_interval(int interval) {
+    const bool success = SDL_GL_SetSwapInterval(interval) >= 0;
+    vsync_enabled = success && (interval != 0);
+    if (!success) {
+        sysLogPrintf(LOG_WARNING, "SDL: failed to set vsync %d: %s", interval, SDL_GetError());
+    }
+    return success;
 }
 
 struct GfxWindowManagerAPI gfx_sdl = { 

port/fast3d/gfx_window_manager_api.h

@@ -22,7 +22,7 @@ struct GfxWindowManagerAPI {
     bool (*can_disable_vsync)(void);
     void *(*get_window_handle)(void);
     void (*set_window_title)(const char *);
-    void (*set_swap_interval)(int);
+    bool (*set_swap_interval)(int);
 };
 
 #endif

port/include/video.h

@@ -4,6 +4,9 @@
 #include <PR/ultratypes.h>
 #include <PR/gbi.h>
 
+// maximum framerate; if the game runs faster than this, things will break
+#define VIDEO_MAX_FPS 200
+
 s32 videoInit(void);
 void videoStartFrame(void);
 void videoSubmitCommands(Gfx *cmds);

port/src/video.c

@@ -46,7 +46,15 @@ s32 videoInit(void)
 
 	gfx_init(wmAPI, renderingAPI, "PD", vidFullscreen, vidWidth, vidHeight, 100, 100);
 
-	wmAPI->set_swap_interval(vidVsync);
+	if (!wmAPI->set_swap_interval(vidVsync)) {
+		vidVsync = 0;
+	}
+
+	if (vidVsync == 0 && vidFramerateLimit == 0) {
+		// cap FPS if there's no vsync to prevent the game from exploding
+		vidFramerateLimit = VIDEO_MAX_FPS;
+	}
+
 	wmAPI->set_target_fps(vidFramerateLimit); // disabled because vsync is on
 	renderingAPI->set_texture_filter((enum FilteringMode)texFilter);
 
@@ -228,7 +236,7 @@ PD_CONSTRUCTOR static void videoConfigInit(void)
 	configRegisterInt("Video.DefaultHeight", &vidHeight, 0, 32767);
 	configRegisterInt("Video.VSync", &vidVsync, -1, 10);
 	configRegisterInt("Video.FramebufferEffects", &vidFramebuffers, 0, 1);
-	configRegisterInt("Video.FramerateLimit", &vidFramerateLimit, 0, 10000);
+	configRegisterInt("Video.FramerateLimit", &vidFramerateLimit, 0, VIDEO_MAX_FPS);
 	configRegisterInt("Video.MSAA", &vidMSAA, 1, 16);
 	configRegisterInt("Video.TextureFilter", &texFilter, 0, 2);
 	configRegisterInt("Video.TextureFilter2D", &texFilter2D, 0, 1);