Exemple #1
0
        public static Vector3m PlaneNormal(Vector3m v0, Vector3m v1, Vector3m v2)
        {
            Vector3m a = v1 - v0;
            Vector3m b = v2 - v0;

            return(a.Cross(b));
        }
Exemple #2
0
        public bool RaySegmentIntersection(out Vector3m intersection, out Rational distanceSquared, Vector3m linePoint1, Vector3m lineVec1, Vector3m linePoint3, Vector3m linePoint4, Vector3m direction)
        {
            var      lineVec2      = linePoint4 - linePoint3;
            Vector3m lineVec3      = linePoint3 - linePoint1;
            Vector3m crossVec1and2 = lineVec1.Cross(lineVec2);
            Vector3m crossVec3and2 = lineVec3.Cross(lineVec2);

            var res = Misc.PointLineDistance(linePoint3, linePoint4, linePoint1);

            if (res == 0) // line and ray are collinear
            {
                var p    = linePoint1 + lineVec1;
                var res2 = Misc.PointLineDistance(linePoint3, linePoint4, p);
                if (res2 == 0)
                {
                    var s = linePoint3 - linePoint1;
                    if (s.X == direction.X && s.Y == direction.Y && s.Z == direction.Z)
                    {
                        intersection    = linePoint3;
                        distanceSquared = s.LengthSquared();
                        return(true);
                    }
                }
            }
            //is coplanar, and not parallel
            if (/*planarFactor == 0.0f && */ crossVec1and2.LengthSquared() > 0)
            {
                var s = crossVec3and2.Dot(crossVec1and2) / crossVec1and2.LengthSquared();
                if (s >= 0)
                {
                    intersection    = linePoint1 + (lineVec1 * s);
                    distanceSquared = (lineVec1 * s).LengthSquared();
                    if ((intersection - linePoint3).LengthSquared() + (intersection - linePoint4).LengthSquared() <=
                        lineVec2.LengthSquared())
                    {
                        return(true);
                    }
                }
            }
            intersection    = Vector3m.Zero();
            distanceSquared = 0;
            return(false);
        }