code: function() {
          var gl = this.context;
          gl.bindBuffer(gl.ARRAY_BUFFER, this._attributeBuffer);
          gl.bufferData(gl.ARRAY_BUFFER, this._attributeArray, gl.STATIC_DRAW);
          gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, this._indexBuffer);
          gl.bufferData(
              gl.ELEMENT_ARRAY_BUFFER,
              this._indexArray,
              gl.STATIC_DRAW
          );
          gl.drawElements(gl.TRIANGLES, this.index_pointer, gl.UNSIGNED_SHORT, 0);
      }
docs: Writes data from the attribute and index arrays to the appropriate buffers, and then calls drawElements.