public static Vector3 GetHoverPoint(Vector3 lp1, Vector3 lp2, Vector3 modelP, float attachR)
{
var _area = Geometric.GetArea(lp1, lp2, modelP); //三角形面积
var _lLength = Vector3.Distance(lp1, lp2); //lp1,lp2长度
var dis = _lLength < 1e-3 ? attachR + 1 : 2 * _area / _lLength; //modelP到lp1,lp2的距离
if (dis > attachR) //太远
{
return(default(Vector3));
}
Vector3 lDir = lp1 - lp2; //直线方向
Vector3 mDir = QuaternionUtility.Euler(0, 90, 0) * lDir; //xz平面上垂直直线方向
Vector3 __S = modelP - mDir * 999;
Vector3 __E = modelP + mDir * 999; //临时的两个线点
if (!Geometric.Meet(__S, __E, lp1, lp2)) //不相交
{
return(default(Vector3));
}
//到这里还能执行的话是相交且接近, 就要计算点
Vector3 res = Geometric.GetCorssPointOfSegment(__E, __S, lp1, lp2);
return(res);
}
public static float GetHoverDis(Vector3 lp1, Vector3 lp2, Vector3 modelP)
{
var _lp1 = new Vector3(lp1.x, 0, lp1.z);
var _lp2 = new Vector3(lp2.x, 0, lp2.z);
var _modelP = new Vector3(modelP.x, 0, modelP.z);
var _area = Geometric.GetArea(_lp1, _lp2, _modelP); //三角形面积
var _lLength = Vector3.Distance(_lp1, _lp2); //lp1,lp2长度
var dis = 2 * _area / _lLength; //modelP到lp1,lp2的距离
return(dis);
}
public static bool AlmostOnLine(Vector3 lineP1, Vector3 lineP2, float width, Vector3 toCheck)
{
Vector3 _lineDir = (lineP2 - lineP1).normalized;
lineP1 += _lineDir * 99;
lineP2 -= _lineDir * 99;
Quaternion q = QuaternionUtility.Euler(0, 90, 0);
Vector3 _rightDir = (q * _lineDir).normalized;
Vector3 lp1Right = lineP1 + _rightDir * 0.5f * width - _lineDir * 0.5f * width;
Vector3 lp1Left = lineP1 - _rightDir * 0.5f * width - _lineDir * 0.5f * width;
Vector3 lp2Right = lineP2 + _rightDir * 0.5f * width + _lineDir * 0.5f * width;
Vector3 lp2Left = lineP2 - _rightDir * 0.5f * width + _lineDir * 0.5f * width;
return(Geometric.IsPointInArea(new[] { lp1Right, lp2Right, lp2Left, lp1Left }, toCheck));
}
public static bool IsPointAlmostOnSegment(Vector3 lineP1, Vector3 lineP2, float width, Vector3 toCheck)
{
Vector3 _lineDir = (lineP2 - lineP1).normalized;
Quaternion q = QuaternionUtility.Euler(0, 90, 0);
Vector3 _rightDir = (q * _lineDir).normalized;
Vector3 diff = _rightDir * width - _lineDir * width;
Vector3 lp1Right = lineP1 + diff;
Vector3 lp1Left = lineP1 - diff;
Vector3 lp2Right = lineP2 + diff;
Vector3 lp2Left = lineP2 - diff;
var res = Geometric.IsPointInArea(new[] { lp1Right, lp2Right, lp2Left, lp1Left }, toCheck);
return(res);
}
/// <summary>
/// 使用向量叉乘来计算任意多边形面积
/// </summary>
/// <param name="points">顺序描述的点集</param>
/// <returns>面积</returns>
public static float GetArea(params Vector3[] points)
{
//去重
List <Vector3> toCalcualte = new List <Vector3>(points);
for (int i = 0; i < toCalcualte.Count; i++)
{
for (int j = 0; j < toCalcualte.Count; j++)
{
if (j != i && toCalcualte[i] == toCalcualte[j])
{
toCalcualte.RemoveAt(j);
j--;
}
}
}
int n = toCalcualte.Count;
for (int i = 0; i < n; i++)
{
if (Geometric.Meet(toCalcualte[i], toCalcualte[(i + 1) % n], toCalcualte[(i + 2) % n], toCalcualte[(i + 3) % n]))
{
var temp = toCalcualte[(i + 2) % n];
toCalcualte[(i + 2) % n] = toCalcualte[(i + 1) % n];
toCalcualte[(i + 1) % n] = temp;
}
}
points = toCalcualte.ToArray();
float area = 0f;
Vector3 ANXI = toCalcualte[0] + Vector3.one * 100;//要尽量远来补平舍入误差
for (int i = 0; i < points.Length; i++)
{
area += cross(ANXI, points[i], points[(i + 1) % points.Length]);
}
area /= 2f;
return(Mathf.Abs(area));
}
public static Vector3 GetHoverPointOfLine(Vector3 lp1, Vector3 lp2, Vector3 modelP, float attachR)
{
var _area = Geometric.GetArea(lp1, lp2, modelP); //三角形面积
var _lLength = Vector3.Distance(lp1, lp2); //lp1,lp2长度
var dis = _lLength < 1e-3 ? attachR + 1 : 2 * _area / _lLength; //modelP到lp1,lp2的距离
if (dis > attachR) //太远
{
return(default(Vector3));
}
Vector3 lDir = lp1 - lp2; //直线方向
Vector3 mDir = QuaternionUtility.Euler(0, 90, 0) * lDir; //xz平面上垂直直线方向
Vector3 __S = modelP - mDir * 99;
Vector3 __E = modelP + mDir * 99; //临时的两个线点
//if (!Geometric.Meet(__S, __E, lp1, lp2))//不相交
//{
// return default(Vector3);
//}
//到这里还能执行的话是相交且接近, 就要计算点
Vector3 res = Geometric.GetCrossPointOfLine(__E, __S, lp1, lp2);
if ((Mathf.Abs(res.x - modelP.x) < 0.01f))
{
res.x = modelP.x;
}
if ((Mathf.Abs(res.z - modelP.z) < 0.01f))
{
res.z = modelP.z;
}
return(res);
}
public static bool IsTwoLinePointPartCover(Vector3 a, Vector3 b, Vector3 c, Vector3 d, float offset = 0.03f)
{
return(Geometric.IsPointAlmostOnSegment(a, b, offset, c) || Geometric.IsPointAlmostOnSegment(a, b, offset, d) ||
Geometric.IsPointAlmostOnSegment(c, d, offset, a) || Geometric.IsPointAlmostOnSegment(c, d, offset, b));
}
public static bool Meet_crossWay(Vector3 p1, Vector3 p2, Vector3 p3, Vector3 p4)
{
Vector3 crossP = GetCrossPointOfLine(p1, p2, p3, p4);
return(Geometric.IsPointOnSegment(p1, p2, crossP) && Geometric.IsPointOnSegment(p3, p4, crossP));
}
