getFrame method

@override Rect getFrame(int index)

Returns the Rect that defines the boundaries of the frame specified by the index.

Implementation

@override
Rect getFrame(int index) {
  // Given a frame index, return the rect that describes that frame in the image.
  if (_image == null) throw ('SpriteSheet.getFrame called before isReady');
  if (index < 0) throw ('Bad index passed to SpriteSheet.getFrame');

  index = index % length;
  int x = index % _cols;
  int y = (index / _cols).floor();

  return Rect.fromLTWH(
    x * _frameWidth,
    y * _frameHeight,
    _frameWidth,
    _frameHeight,
  );
}