public static Int3 changeAbsolute2Relative(Int3 point, Int3 originPoint, ushort angle)
{
//originPoint为图中A点，directionPoint为图中B点，changePoint为图中C点
Int3 rePoint = new Int3();
Int3 directionPoint = FixMath.DecomposeAngle(1000, angle);
directionPoint.x = originPoint.x + directionPoint.x;
directionPoint.y = originPoint.y + directionPoint.y;
directionPoint.y = originPoint.z + directionPoint.z;
if (originPoint == directionPoint) //方向点跟原点重合，就用平行于原坐标的x轴来算就行了
{ //AB点重合，方向指向哪里都没所谓，肯定按原来的做方便
rePoint.x = point.x - originPoint.x;
rePoint.y = point.y - originPoint.y;
}
else
{
//计算三条边
//计算三条边
Fix64 a = (Fix64)DistanceSqr(directionPoint, point);
a = Fix64.Sqrt(a);
Fix64 b = (Fix64)DistanceSqr(point, originPoint);
b = Fix64.Sqrt(b);
Fix64 c = (Fix64)DistanceSqr(directionPoint, originPoint);
c = Fix64.Sqrt(c);
Fix64 cosA = (b * b + c * c - a * a) / ((Fix64)2 * b * c); //余弦
Fix64 xpos = a * cosA; //相对坐标x
Fix64 ypos = Fix64.Sqrt(a * a - xpos * xpos); //相对坐标y
rePoint.x = (int)xpos;
rePoint.y = (int)ypos;
}
return(rePoint);
}
private Vector3 GetU3DForwards()
{
Int3 perform = FixMath.DecomposeAngle(1000, angle);
return(perform.ToVector3());
}