code: function transform(mat2d) {
           this.currentTransform.multiply(mat2d);
  
           if (this.settings.subPixel === false) {
             // snap position values to pixel grid
             var a = this.currentTransform.val;
             a[6] = ~~a[6];
             a[7] = ~~a[7];
           }
         }
docs: Multiply given matrix into the renderer tranformation matrix
  @name transform
  @memberOf me.WebGLRenderer.prototype
  @function
  @param {me.Matrix2d} mat2d Matrix to transform by