X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=freeglut-1.3%2Ffreeglut_display.c;h=d6ce1cb76d9797873e45bf08b504014618f47787;hb=9d66916bab11e22ff2b670638be3a50e604897a1;hp=9117a10952197bc7dd3d848ca2585afd163a6427;hpb=8fca860c3dd3f20027fc730c386047166c3b9ee7;p=freeglut

diff --git a/freeglut-1.3/freeglut_display.c b/freeglut-1.3/freeglut_display.c
index 9117a10..d6ce1cb 100644
--- a/freeglut-1.3/freeglut_display.c
+++ b/freeglut-1.3/freeglut_display.c
@@ -74,6 +74,11 @@ void FGAPIENTRY glutSwapBuffers( void )
      */
     glFlush();
 
+    /*
+     * If it's single-buffered, we shouldn't be here.
+     */
+    if ( ! fgStructure.Window->Window.DoubleBuffered ) return ;
+
 #if TARGET_HOST_UNIX_X11
     /*
      * Issue the glXSwapBuffers call and be done with it
@@ -87,6 +92,22 @@ void FGAPIENTRY glutSwapBuffers( void )
     SwapBuffers( fgStructure.Window->Window.Device );
 
 #endif
+
+    /* GLUT_FPS env var support */
+    if (fgState.FPSInterval) {
+        GLint t = glutGet(GLUT_ELAPSED_TIME);
+        fgState.SwapCount++;
+        if (fgState.SwapTime == 0)
+            fgState.SwapTime = t;
+        else if (t - fgState.SwapTime > fgState.FPSInterval) {
+            float time = 0.001 * (t - fgState.SwapTime);
+            float fps = (float) fgState.SwapCount / time;
+            fprintf(stderr, "FreeGLUT: %d frames in %.2f seconds = %.2f FPS\n",
+                    fgState.SwapCount, time, fps);
+            fgState.SwapTime = t;
+            fgState.SwapCount = 0;
+        }
+    }
 }
 
 /*