calculateScale method

double calculateScale(
  1. double angle
)

计算缩放参数

Implementation

double calculateScale(double angle) {
  angle = angle % 360;
  if (angle > 180) {
    angle = 360 - angle;
  }

  angle += 30; //修正一下，视觉效果貌似更好

  var scale = angle / 180.0;

  if (scale > 1) {
    scale = 1;
  } else if (scale < minScale) {
    scale = minScale;
  }

  return scale;
}