本文介绍了两个坐标的相对基本方向的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
定义了以下枚举:
public enum Direction
{
North,
South,
East,
West,
Northeast,
Northwest,
Southeast,
Southwest,
Undefined
}
给出二维空间中的两组坐标，我想确定从点2到1的相对基本方向.
Given two sets of coordinates in two-dimensional space, I'd like to determine the relative cardinal direction from Point 2 to 1.
示例:
- P1(1,1)和P2(0,1)返回Direction.North因为P2在P1以北
- P1(1,1)和P2(5,4)返回Direction.Southeast
- P1(1,1)和P2(1,1)返回Direction.Undefined
我当前的方法涉及很多条件，即
My current approach involves a bunch of conditions, i.e.
if (P1.X == P2.X)
{
// either North, South or Undefined
if (P1.Y < P2.Y)
return Direction.South;
else if (P1.Y > P2.Y)
return Direction.North,
else
return Direction.Undefined;
}
else if (P1.Y == P2.Y)
{
...
}
else
{
...
}
我正在寻找一个更短，更优雅的解决方案.
I'm seeking a shorter and more elegant solution.
推荐答案
我的3美分-我正在等待改善
My 3 cents - i'm waiting for improvements
这是枚举:
public enum Direction
{
North = 0,
South = 4,
East = 6,
West = 2,
Northeast = 7,
Northwest = 1,
Southeast = 5,
Southwest = 3,
Undefined = -1
}
转换为:
public static Direction GetDirection(Point p1, Point p2) {
double angle = Math.Atan2(p2.Y - p1.Y, p2.X - p1.X);
angle += Math.PI;
angle /= Math.PI / 4;
int halfQuarter = Convert.ToInt32(angle);
halfQuarter %= 8;
return (Direction)halfQuarter;
}
但是它不会返回Direction.Undefined，因为
(来自 https://msdn.microsoft .com/library/system.math.atan2(v = vs.110).aspx )
这篇关于两个坐标的相对基本方向的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！