docs: function(frames, timestep) {
                  timestep = timestep || milliSecPerFrame;
                  while (frames-- > 0) {
                      var frameData = {
                          frame: frame++,
                          dt: timestep
                      };
                      Crafty.trigger("EnterFrame", frameData);
                      Crafty.trigger("UpdateFrame", frameData);
                      Crafty.trigger("ExitFrame", frameData);
                  }
                  Crafty.trigger("PreRender");
                  Crafty.trigger("RenderScene");
                  Crafty.trigger("PostRender");
              }