calculateOffset method

Offset calculateOffset(
  1. double angle
)

计算椭圆轨迹的点

Implementation

Offset calculateOffset(double angle) {
  double width = widgetWidth * 0.7; //椭圆宽
  double radiusOuterX = width / 2;
  double radiusOuterY = ellipseHeight;

  double angleOuter = (2 * pi / 360) * angle;
  double x = radiusOuterX * sin(angleOuter);
  double y = radiusOuterY > 0 ? radiusOuterY * cos(angleOuter) : 0;
  return Offset(x + (widgetWidth - itemConfig.width) / 2, -y);
}