Rect.fromCircle constructor

Rect.fromCircle({Offset center, double radius })

Construct a rectangle that bounds the given circle.

The center argument is assumed to be an offset from the origin.

Implementation 

Rect.fromCircle({ Offset center, double radius }) {
  _value
    ..[0] = center.dx - radius
    ..[1] = center.dy - radius
    ..[2] = center.dx + radius
    ..[3] = center.dy + radius;
}