m3eGradientSpanRect function

Rect m3eGradientSpanRect({ required GlobalKey<State<StatefulWidget>> hostKey, required BuildContext context, required Rect local, })

Maps local into the box of hostKey so siblings share one gradient span.

Returns local untouched until both boxes are laid out.

Implementation

Rect m3eGradientSpanRect({
  required GlobalKey hostKey,
  required BuildContext context,
  required Rect local,
}) {
  final host = hostKey.currentContext?.findRenderObject() as RenderBox?;
  final box = context.findRenderObject() as RenderBox?;
  if (host == null || box == null || !host.hasSize || !box.hasSize) {
    return local;
  }
  final Offset origin = box.localToGlobal(Offset.zero, ancestor: host);
  return Rect.fromLTWH(
    -origin.dx,
    -origin.dy,
    host.size.width,
    host.size.height,
  );
}