Cache the swap control setting, even on Mesa.

--HG--
branch : SDL-1.2
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%404002

src/video/x11/SDL_x11gl.c

@@ -283,15 +283,16 @@ int X11_GL_CreateContext(_THIS)
 	}
 	if ( !glXExtensionSupported(this, "GLX_MESA_swap_control") ) {
 		this->gl_data->glXSwapIntervalMESA = NULL;
-		this->gl_data->glXGetSwapIntervalMESA = NULL;
 	}
 	if ( this->gl_config.swap_control >= 0 ) {
+        int rc = -1;
 		if ( this->gl_data->glXSwapIntervalMESA ) {
-			this->gl_data->glXSwapIntervalMESA(this->gl_config.swap_control);
+			rc = this->gl_data->glXSwapIntervalMESA(this->gl_config.swap_control);
 		} else if ( this->gl_data->glXSwapIntervalSGI ) {
-			if (this->gl_data->glXSwapIntervalSGI(this->gl_config.swap_control) == 0) {
-				this->gl_data->sgi_swap_interval = this->gl_config.swap_control;
+			rc = this->gl_data->glXSwapIntervalSGI(this->gl_config.swap_control);
 		}
+		if (rc == 0) {
+			this->gl_data->swap_interval = this->gl_config.swap_control;
 		}
 	}
 #else
@@ -412,11 +413,9 @@ int X11_GL_GetAttribute(_THIS, SDL_GLattr attrib, int* value)
 		}
 		break;
 	    case SDL_GL_SWAP_CONTROL:
-		if ( this->gl_data->glXGetSwapIntervalMESA ) {
-			*value = this->gl_data->glXGetSwapIntervalMESA();
-			return 0;
-		} else if ( this->gl_data->glXSwapIntervalSGI ) {
-			*value = this->gl_data->sgi_swap_interval;
+		if ( ( this->gl_data->glXSwapIntervalMESA ) ||
+		     ( this->gl_data->glXSwapIntervalSGI ) ) {
+			*value = this->gl_data->swap_interval;
 			return 0;
 		} else {
 			unsupported = 1;
@@ -469,7 +468,6 @@ void X11_GL_UnloadLibrary(_THIS)
 		this->gl_data->glXSwapBuffers = NULL;
 		this->gl_data->glXSwapIntervalSGI = NULL;
 		this->gl_data->glXSwapIntervalMESA = NULL;
-		this->gl_data->glXGetSwapIntervalMESA = NULL;
 
 		this->gl_config.dll_handle = NULL;
 		this->gl_config.driver_loaded = 0;
@@ -530,8 +528,6 @@ int X11_GL_LoadLibrary(_THIS, const char* path)
 		(int (*)(int)) GL_LoadFunction(handle, "glXSwapIntervalSGI");
 	this->gl_data->glXSwapIntervalMESA =
 		(GLint (*)(unsigned)) GL_LoadFunction(handle, "glXSwapIntervalMESA");
-	this->gl_data->glXGetSwapIntervalMESA =
-		(GLint (*)(void)) GL_LoadFunction(handle, "glXGetSwapIntervalMESA");
 
 	if ( (this->gl_data->glXChooseVisual == NULL) || 
 	     (this->gl_data->glXCreateContext == NULL) ||

src/video/x11/SDL_x11gl_c.h

@@ -73,9 +73,7 @@ struct SDL_PrivateGLData {
 
     int (*glXSwapIntervalSGI) ( int interval );
     GLint (*glXSwapIntervalMESA) ( unsigned interval );
-    GLint (*glXGetSwapIntervalMESA) ( void );
-
-    int sgi_swap_interval;
+    int swap_interval;
 #endif /* SDL_VIDEO_OPENGL_GLX */
 };
 

src/video/x11/SDL_x11video.c

@@ -122,7 +122,7 @@ static SDL_VideoDevice *X11_CreateDevice(int devindex)
 		SDL_memset(device->gl_data, 0, (sizeof *device->gl_data));
 
 #if SDL_VIDEO_OPENGL_GLX
-		device->gl_data->sgi_swap_interval = -1;
+		device->gl_data->swap_interval = -1;
 #endif
 
 		/* Set the driver flags */