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源码地址：https://download.csdn.net/download/qq_37310110/10886004
一.判断目标点是否在某一圆形区域内
定义圆形
public class Circle {
public Vector2 Center;
public float Radius;
public Circle(Vector2 center, float radius)
{
this.Center = center;
this.Radius = radius;
}
public bool Contains( Vector2 point)
{
Vector2 vector = point - this.Center;
return (vector.SqrMagnitude() <= (this.Radius * this.Radius));
}
public Vector2 Eval(float t)
{
return new Vector2(this.Center.x + (this.Radius * Mathf.Cos(t)), this.Center.y + (this.Radius * Mathf.Sin(t)));
}
}测试脚本
public class CircleTest : MonoBehaviour {
public Transform Point;
public Transform cCircle;
Circle circle;
private void OnDrawGizmos()
{
if (circle != null)
{
DrawCircle(circle);
//Gizmos.DrawSphere(Point.position, 0.11f);
}
}
private void Update()
{
if (Input.GetKeyDown(KeyCode.Q))
{
circle = new Circle(cCircle.position, cCircle.localScale.x);
bool cont = circle.Contains(Point.position);
if (cont)
{
Debug.Log("目标点在矩形范围内");
}
else
{
Debug.Log("目标点不在矩形范围内");
}
}
}
protected void DrawCircle( Circle circle)
{
Gizmos.color = Color.blue;
int count = 40;//绘制圆形基础点的个数 适当即可
float delta = 2f * Mathf.PI / count;
Vector3 prev = circle.Eval(0);
for (int i = 1; i <= count; ++i)
{
Vector3 curr = circle.Eval(i * delta);
Gizmos.DrawLine(prev, curr);
prev = curr;
}
}
}
结果
二.判断目标点是否在指定的三角形区域内
定义三角形
public class Triangle
{
public enum Orientations
{
CW,//三个点顺时针
CCW,//三个点逆时针
None//不清楚点的顺序
}
public Vector2 V0;
public Vector2 V1;
public Vector2 V2;
public Triangle(Vector2 v0, Vector2 v1, Vector2 v2)
{
this.V0 = v0;
this.V1 = v1;
this.V2 = v2;
}
public static Triangle CreateTriangle2(Transform v0, Transform v1, Transform v2)
{
return new Triangle(v0.position, v1.position, v2.position);
}
public Orientations CalcOrientation(float threshold = 1E-05f)
{
float num = this.CalcDeterminant();
if (num > threshold)
{
return Orientations.CCW;
}
if (num < -threshold)
{
return Orientations.CW;
}
return Orientations.None;
}
public float CalcDeterminant()
{
return ((((((this.V1.x * this.V2.y) + (this.V0.x * this.V1.y)) + (this.V2.x * this.V0.y)) - (this.V1.x * this.V0.y)) - (this.V2.x * this.V1.y)) - (this.V0.x * this.V2.y));
}
public bool Contains(Vector2 point)
{
bool flag = (((point.x - this.V1.x) * (this.V0.y - this.V1.y)) - ((point.y - this.V1.y) * (this.V0.x - this.V1.x))) < 0f;
bool flag2 = (((point.x - this.V2.x) * (this.V1.y - this.V2.y)) - ((point.y - this.V2.y) * (this.V1.x - this.V2.x))) < 0f;
if (flag != flag2)
{
return false;
}
bool flag3 = (((point.x - this.V0.x) * (this.V2.y - this.V0.y)) - ((point.y - this.V0.y) * (this.V2.x - this.V0.x))) < 0f;
return (flag2 == flag3);
}
/// <summary>
/// 当已经知道 三个顶点的顺序是逆时针方向的时候使用
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public bool ContainsCCW(Vector2 point)
{
if ((((point.x - this.V0.x) * (this.V1.y - this.V0.y)) - ((point.y - this.V0.y) * (this.V1.x - this.V0.x))) > 0f)
{
return false;
}
if ((((point.x - this.V1.x) * (this.V2.y - this.V1.y)) - ((point.y - this.V1.y) * (this.V2.x - this.V1.x))) > 0f)
{
return false;
}
if ((((point.x - this.V2.x) * (this.V0.y - this.V2.y)) - ((point.y - this.V2.y) * (this.V0.x - this.V2.x))) > 0f)
{
return false;
}
return true;
}
/// <summary>
/// 当已经知道 三个顶点的顺序是顺时针方向的时候使用
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public bool ContainsCW(Vector2 point)
{
if ((((point.x - this.V0.x) * (this.V1.y - this.V0.y)) - ((point.y - this.V0.y) * (this.V1.x - this.V0.x))) < 0f)
{
return false;
}
if ((((point.x - this.V1.x) * (this.V2.y - this.V1.y)) - ((point.y - this.V1.y) * (this.V2.x - this.V1.x))) < 0f)
{
return false;
}
if ((((point.x - this.V2.x) * (this.V0.y - this.V2.y)) - ((point.y - this.V2.y) * (this.V0.x - this.V2.x))) < 0f)
{
return false;
}
return true;
}
}测试脚本
public class TriangleTest : MonoBehaviour {
public Transform Point;
public Transform V0, V1, V2;
Triangle triangle;
private void Update()
{
if (Input.GetKeyDown(KeyCode.Q))
{
triangle = Triangle.CreateTriangle2(V0, V1, V2);
Triangle.Orientations orientation = triangle.CalcOrientation();
bool cont = false;
if (orientation == Triangle.Orientations.CCW)
{
cont = triangle.Contains(Point.position);
//cont1 = triangle.ContainsCCW(Point.position); // 如果你知道三角形方向(顶点顺序方向)，就用这个
}
else if (orientation == Triangle.Orientations.CW)
{
cont = triangle.Contains(Point.position);
//cont1 = triangle.ContainsCW(Point.position); // 如果你知道三角形方向(顶点顺序方向)，就用这个
}
else // Degenerate
{
Debug.LogError("Triangle is degenerate");
}
if (cont)
{
Debug.Log("目标点在矩形范围内");
}
else
{
Debug.Log("目标点不在矩形范围内");
}
}
}
private void OnDrawGizmos()
{
if (triangle!=null)
{
DrawTriangle( triangle);
}
}
void DrawTriangle( Triangle triangle)
{
Gizmos.color = Color.blue;
Gizmos.DrawLine(triangle.V0, triangle.V1);
Gizmos.DrawLine(triangle.V1, triangle.V2);
Gizmos.DrawLine(triangle.V2, triangle.V0);
}
}
结果
源码地址：https://download.csdn.net/download/qq_37310110/10886004