docs: private static double arcAngle(Point center, Point a, Point b, Rect area, int radius) {
          double angle = threePointsAngle(center, a, b);
          Point innerPoint = findMidnormalPoint(center, a, b, area, radius);
          Point midInsectPoint = new Point((a.x + b.x) / 2, (a.y + b.y) / 2);
          double distance = pointsDistance(midInsectPoint, innerPoint);
          if (distance > radius) {
              return 360 - angle;
          }
          return angle;
      }