circlePoint function

Offset circlePoint(
  1. num radius,
  2. num angle, [
  3. Offset center = Offset.zero
])

给定一个半径和圆心计算给定角度对应的位置坐标

Implementation

Offset circlePoint(num radius, num angle, [Offset center = Offset.zero]) {
  double x = center.dx + radius * cos(angle * Constants.angleUnit);
  double y = center.dy + radius * sin(angle * Constants.angleUnit);
  return Offset(x, y);
}