code: function(rect, fillStyle, useSketch) {
          if (!this.useCanvas) {
              return;
          }
  
          var context = this._getContext( useSketch );
          context.save();
          context.fillStyle = fillStyle;
          context.fillRect(rect.x, rect.y, rect.width, rect.height);
          context.restore();
      }
docs: private