throttle glut requestAnimationFrames; fixes #2183

1 files changed, 4 insertions, 1 deletions

diff --git a/src/library_glut.js b/src/library_glut.js
index 167e5272..445e08a4 100644
--- a/src/library_glut.js
+++ b/src/library_glut.js
@@ -22,6 +22,7 @@ var LibraryGLUT = {
     windowY: 0,
     windowWidth: 0,
     windowHeight: 0,
+    requestedAnimationFrame: false,
 
     saveModifiers: function(event) {
       GLUT.modifiers = 0;
@@ -484,8 +485,10 @@ var LibraryGLUT = {
   glutSwapBuffers: function() {},
 
   glutPostRedisplay: function() {
-    if (GLUT.displayFunc) {
+    if (GLUT.displayFunc && !GLUT.requestedAnimationFrame) {
+      GLUT.requestedAnimationFrame = true;
       Browser.requestAnimationFrame(function() {
+        GLUT.requestedAnimationFrame = false;
         if (ABORT) return;
         Runtime.dynCall('v', GLUT.displayFunc);
       });