message: Fix single canvas painting.
diff: @@ -478,6 +478,9 @@ Painter.prototype = {
  * @return {module:zrender/Layer}
  */
  getLayer: function (zlevel, virtual) {
  + if (this._singleCanvas && !this._needsManuallyCompositing) {
  + zlevel = CANVAS_ZLEVEL;
  + }
  var layer = this._layers[zlevel];
  if (!layer) {
  // Create a new layer
  