function transformDirection(direction, transform, invert) {
  // Pick a base, ensure that transform result will not be (0, 0).
  var hBase = transform[4] === 0 || transform[5] === 0 || transform[0] === 0 ? 1 : Math.abs(2 * transform[4] / transform[0]);
  var vBase = transform[4] === 0 || transform[5] === 0 || transform[2] === 0 ? 1 : Math.abs(2 * transform[4] / transform[2]);
  var vertex = [direction === 'left' ? -hBase : direction === 'right' ? hBase : 0, direction === 'top' ? -vBase : direction === 'bottom' ? vBase : 0];
  vertex = graphic_applyTransform(vertex, transform, invert);
  return Math.abs(vertex[0]) > Math.abs(vertex[1]) ? vertex[0] > 0 ? 'right' : 'left' : vertex[1] > 0 ? 'bottom' : 'top';
}
@param direction 'left' 'right' 'top' 'bottom'
@param transform Transform matrix: like [1, 0, 0, 1, 0, 0]
@param invert Whether use invert matrix.
@return Transformed direction. 'left' 'right' 'top' 'bottom'