TransferMode transferMode

A transfer mode to apply when a shape is drawn or a layer is composited.

The source colors are from the shape being drawn (e.g. from Canvas.drawPath) or layer being composited (the graphics that were drawn between the Canvas.saveLayer and Canvas.restore calls), after applying the colorFilter, if any.

The destination colors are from the background onto which the shape or layer is being composited.

Defaults to TransferMode.srcOver.

Source 

TransferMode get transferMode {
  final int encoded = _data.getInt32(_kTransferModeOffset, _kFakeHostEndian);
  return TransferMode.values[encoded ^ _kTransferModeDefault];
}
void transferMode=(TransferMode value)

Source 

set transferMode(TransferMode value) {
  assert(value != null);
  final int encoded = value.index ^ _kTransferModeDefault;
  _data.setInt32(_kTransferModeOffset, encoded, _kFakeHostEndian);
}