message: Add comment about modulo operator
diff: @@ -188,6 +188,8 @@ export default class ImageView extends React.Component<IProps, IState> {
  // relative to the center of the image, accounting for rotation.
  let offsetX;
  let offsetY;
  + // The modulo operator can return negative values for some
  + // rotations, so we have to do some extra work to normalize it
  switch (((this.state.rotation % 360) + 360) % 360) {
  case 0:
  offsetX = this.image.current.clientWidth / 2 - anchorX;
  