typedef int PK_FACE_coi_t; PK_FACE_coi_t will be one of the following PK_FACE_coi_yes_c Two faces are coincident to the given tolerance. PK_FACE_coi_yes_reversed_c Two faces are coincident to the given tolerance but their normals are reversed. PK_FACE_coi_no_topol_c The two faces are not coincident. The numbers of holes are different. Note that isolated loops and wire edges are ignored. PK_FACE_coi_no_bound_1_c The two faces are not coincident. At least one point on the boundary of face No. 1 is not coincident with the boundary of face No. 2. The point is returned. PK_FACE_coi_no_bound_2_c The two faces are not coincident. At least one point on the boundary of face No. 2 is not coincident with the boundary of face No. 1. The point is returned. PK_FACE_coi_no_face_1_c The two faces are not coincident. At least one point on face No. 1 is not coincident with face No. 2. The point is returned. PK_FACE_coi_no_face_2_c The two faces are not coincident. At least a point on face No. 2 is not coincident with face No. 1. The point is returned. PK_FACE_coi_no_rubber_c At least one of the faces does not have a surface attached.