/// <summary>
/// ///计算pos到直线(lineSt, lineEnd)的最短距离
/// </summary>
/// <param name="pos"></param>
/// <param name="lineSt"></param>
/// <param name="lineEnd"></param>
/// <param name="lineIsSegment">是否为线段</param>
/// <returns></returns>
public static double LinePointDistance(Vector2_DW lineSt, Vector2_DW lineEnd, Vector2_DW pos, bool lineIsSegment)
{
double disRet = 0;
if (lineIsSegment == false)
{
disRet = Vector2_DW.Cross(lineSt, lineEnd, pos) / Vector2_DW.Distance(lineSt, lineEnd);
}
else
{
Vector2_DW ab = lineEnd - lineSt;
Vector2_DW bc = pos - lineEnd;
Vector2_DW ac = pos - lineSt;
if (Vector2_DW.Dot(ab, bc) > 0)//pos在lineEnd外侧
{
disRet = Vector2_DW.Distance(pos, lineEnd);
}
else if (Vector2_DW.Dot(ab, ac) > 0)//pos在lineEnd外侧
{
disRet = Vector2_DW.Distance(pos, lineSt);
}
else//pos在lineSt与lineEnd之间
{
disRet = Vector2_DW.Cross(lineSt, lineEnd, pos) / Vector2_DW.Distance(lineSt, lineEnd);
}
}
return(Math.Abs(disRet));
}
//返回两个向量之间的夹角(角度制)(0-180)
static public double Angle(Vector2_DW from, Vector2_DW to)
{
return(Math.Acos(ToolsMath_DW.Clamp(Vector2_DW.Dot(from.Normalize(), to.Normalize()), -1f, 1f)) * 57.29578f);
}
