Returns 6x the signed volume of the tetrahedron defined by given 3D points.
remarks
Returns positive or negative value if d lies below/above the plane defined by a,b,c respectively (where "below" is defined such that a,b,c are counterclockwise if viewed from above). Returns zero if all points are coplanar.
Returns 6x the signed volume of the tetrahedron defined by given 3D points.
Returns positive or negative value if
d
lies below/above the plane defined by a,b,c respectively (where "below" is defined such that a,b,c are counterclockwise if viewed from above). Returns zero if all points are coplanar.Based on code by Jonathan R. Shewchuk http://www.cs.cmu.edu/afs/cs/project/quake/public/code/predicates.c