//New 已测
/// <summary>
/// 计算点到经过两点的直线的距离
/// </summary>
/// <param name="sPos"></param>
/// <param name="sPos1"></param>
/// <param name="sPos2"></param>
/// <returns></returns>
public static FP DistanceFromPointToLine(TSVector2 sPos, TSVector2 sPos1, TSVector2 sPos2)
{
TSVector2 line1 = sPos2 - sPos1;
TSVector2 line2 = sPos - sPos1;
if (line1 == TSVector2.zero)
{
return(line2.magnitude);
}
return(TSMath.Abs(line2.x * line1.y - line2.y * line1.x) / line1.magnitude);
}
//New 已测
/// <summary>
/// 检测圆与线段是否相交
/// </summary>
/// <param name="sOrgPos"></param>
/// <param name="sOffset"></param>
/// <param name="sCenter"></param>
/// <param name="nRadius"></param>
/// <param name="sCrossPoint"></param>
/// <returns></returns>
public static bool CheckCicleAndLine(TSVector2 sOrgPos, TSVector2 sOffset, TSVector2 sCenter, FP nRadius, out TSVector2 sCrossPoint)
{
//推导过程
//http://blog.csdn.net/rabbit729/article/details/4285119
sCrossPoint = sCenter;
FP nDis = sOffset.magnitude;
TSVector2 d = sOffset.normalized;
TSVector2 e = sCenter - sOrgPos;
FP a = (e.x * d.x + e.y * d.y);
FP f = a * a + nRadius * nRadius - e.LengthSquared();
if (f >= 0)
{
FP s = TSMath.Sqrt(f);
FP t1 = a - s;
FP t2 = a + s;
if (TSMath.Abs(t1) > TSMath.Abs(t2))
{
FP fTemp = t1;
t1 = t2;
t2 = fTemp;
}
//射线原点在圆外
if ((t1 >= 0) && (t1 - nDis) <= 0)
{
sCrossPoint.x = sOrgPos.x + t1 * d.x;
sCrossPoint.y = sOrgPos.y + t1 * d.y;
return(true);
}
//这里说明射线原点在圆内
if (t2 >= 0)
{
//如果与圆有碰撞
if ((t2 - nDis) <= 0)
{
sCrossPoint.x = sOrgPos.x + t2 * d.x;
sCrossPoint.y = sOrgPos.y + t2 * d.y;
return(true);
}
//如果两个点都在圆内
else
{
sCrossPoint = sOrgPos;
return(true);
}
}
}
return(false);
}
//NEW已测
/// <summary>
/// 检测一个点的xz平面投影是否处于2DAabb内
/// </summary>
/// <param name="sCenter"></param>
/// <param name="nHalfWidth"></param>
/// <param name="nHalfHeight"></param>
/// <param name="sPos"></param>
/// <returns></returns>
public static bool CheckAabbAndPos(TSVector2 sCenter, FP nHalfWidth, FP nHalfHeight, TSVector2 sPos)
{
TSVector2 sOffset = sPos - sCenter;
if (TSMath.Abs(sOffset.x) > nHalfWidth)
{
return(false);
}
if (TSMath.Abs(sOffset.y) > nHalfHeight)
{
return(false);
}
return(true);
}
