X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=freeglut-1.3%2Ffreeglut_display.c;h=de198415fce2791c47d98365ea99cd0697c270f8;hb=074d49cf100b2aa810bf7086c4d7d910d5d00dfd;hp=900b9d0d39ba4f34f79350ac09aacaf01b0aa0df;hpb=4c26f132450ad50c9b5ccf43f143ff26d53722fd;p=freeglut

diff --git a/freeglut-1.3/freeglut_display.c b/freeglut-1.3/freeglut_display.c
index 900b9d0..de19841 100644
--- a/freeglut-1.3/freeglut_display.c
+++ b/freeglut-1.3/freeglut_display.c
@@ -92,6 +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 = 0.001f * (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;
+        }
+    }
 }
 
 /*