project method

  1. @override
Shape project(
  1. Transform2D transform, [
  2. Shape? target
])
override

Returns the result of applying an affine transformation to the shape.

Certain shapes may be transformed into shapes of a different kind during the projection. For example, a Circle may transform into an Ellipse, and Rectangle into a Polygon.

If target is provided and it has a proper type, then this method should modify the target in-place and return it. If target is null, or if its type is not compatible with the requested transform, then the method should create and return a new Shape.

Implementation

@override
Shape project(Transform2D transform, [Shape? target]) {
  if (transform.isConformal) {
    final newCenter = transform.localToGlobal(_center);
    final newRadius = transform.scale.x.abs() * _radius;
    if (target is Circle) {
      target._center.setFrom(newCenter);
      target._radius = newRadius;
      _aabb = null;
      return target;
    } else {
      return Circle(newCenter, newRadius);
    }
  }
  throw UnimplementedError();
}