CGAL::compare_dihedral_angle

Comparison_result compare_dihedral_angle ( Point_3<K> a1, Point_3<K> b1, Point_3<K> c1, Point_3<K> d1, K::FT cosine)
compares the dihedral angles 1 and 2, where 1 is the dihedral angle, in [0, π], of the tetrahedron (a1, b1, c1, d1) at the edge (a1, b1), and 2 is the angle in [0, π] such that cos(2) = cosine. The result is the same as compare_dihedral_angle(b1-a1, c1-a1, d1-a1, cosine).
Precondition: a1, b1, c1 are not collinear, and a1, b1, d1 are not collinear.

Comparison_result
compare_dihedral_angle ( Point_3<K> a1,
Point_3<K> b1,
Point_3<K> c1,
Point_3<K> d1,
Point_3<K> a2,
Point_3<K> b2,
Point_3<K> c2,
Point_3<K> d2)
compares the dihedral angles 1 and 2, where i is the dihedral angle in the tetrahedron (ai, bi, ci, di) at the edge (ai, bi). These two angles are computed in [0, π]. The result is the same as compare_dihedral_angle(b1-a1, c1-a1, d1-a1, b2-a2, c2-a2, d2-a2).
Precondition: For i {1,2}, ai, bi, ci are not collinear, and ai, bi, di are not collinear.

Comparison_result compare_dihedral_angle ( K::Vector_3 u1, K::Vector_3 v1, K::Vector_3 w1, K::FT cosine)
compares the dihedral angles 1 and 2, where 1 is the dihedral angle, in [0, π], between the vectorial planes defined by (u1, v1) and (u1, w1), and 2 is the angle in [0, π] such that cos(2) = cosine.
Precondition: u1 and v1 are not collinear, and u1 and w1 are not collinear.

Comparison_result
compare_dihedral_angle ( K::Vector_3 u1,
K::Vector_3 v1,
K::Vector_3 w1,
K::Vector_3 u2,
K::Vector_3 v2,
K::Vector_3 w2)
compares the dihedral angles 1 and 2, where i is the dihedral angle between the vectorial planes defined by (ui, vi) and (ui, wi). These two angles are computed in [0, π].
Precondition: For i {1,2}, ui and vi are not collinear, and ui and wi are not collinear.