getDerivativeOnArc function

Offset getDerivativeOnArc(
  1. Rect rect,
  2. double t
)

Implementation

Offset getDerivativeOnArc(Rect rect, double t) {
  double rx = rect.width / 2, ry = rect.height / 2;
  return Offset(-rx * sin(t), ry * cos(t));
}