Function

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 theta1 and theta2, where theta1 is the dihedral angle, in [0, π], of the tetrahedron (a1, b1, c1, d1) at the edge (a1, b1), and theta2 is the angle in [0, π] such that cos(theta2) = 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 theta1 and theta2, where thetai 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 theta1 and theta2, where theta1 is the dihedral angle, in [0, π], between the vectorial planes defined by (u1, v1) and (u1, w1), and theta2 is the angle in [0, π] such that cos(theta2) = 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 theta1 and theta2, where thetai 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.