comment

mandelbrot.c

@@ -51,10 +51,11 @@ void drawmandelbrot(SDL_Surface *surface) {
     }
   }
 
+  /* Update the screen a final time. */
+  SDL_Flip(surface);
   if (SDL_MUSTLOCK(surface)) {
     SDL_UnlockSurface(surface);
   }
-  SDL_Flip(surface);
 }
 
 int main(int argc, char *argv[]) {