显示FPS

定制主题 - 内嵌Html内容（body）

<!-- 显示FPS，非桌面设备下不会显示 -->
<script>
  $('body').before('<div id="fps" class="is-hidden-not-desktop" style="color:green;z-index:99999;position:fixed;top:12px;left:10px;font-weight:bold;"></div>');
  var showFPS = (function() {
      var requestAnimationFrame = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(callback) {
        window.setTimeout(callback, 1000 / 60);
      }

      var e, pe, pid, fps, last, offset, step, appendFps;
      fps = 0;
      last = Date.now();
      step = function() {
        offset = Date.now() - last;
        fps += 1;
        if (offset >= 1000) {
          last += offset;
          appendFps(fps);
          fps = 0;
        }
        requestAnimationFrame(step);
      };
      
      appendFps = function(fps) {
        $('#fps').html(fps + ' FPS ');
      };
      
      step();
    }
  )();
</script>
<!-- 显示FPS -->