def solve_triangular_faces(self):
"""Modify the decomposition mesh from polylines to make it a quad mesh by converting the degenerated quad faces that appear as triangular faces.
"""
mesh = self.mesh
for fkey in list(mesh.faces()):
if len(mesh.face_vertices(fkey)) == 3:
boundary_vertices = [vkey for vkey in mesh.face_vertices(fkey) if mesh.is_vertex_on_boundary(vkey)]
case = sum(mesh.is_vertex_on_boundary(vkey) for vkey in mesh.face_vertices(fkey))
if case == 1:
#convert triangular face to quad by duplicating the boundary vertex
#due to compas_singular face vertices at the same location
u = boundary_vertices[0]
v = mesh.add_vertex(attr_dict = {attr: xyz for attr, xyz in zip(['x', 'y', 'z'], mesh.vertex_coordinates(u))})
# modify adjacent faces
vertex_faces = mesh.vertex_faces(u, ordered = True)
mesh_substitute_vertex_in_faces(mesh, u, v, vertex_faces[: vertex_faces.index(fkey)])
# modify triangular face
mesh_insert_vertex_on_edge(mesh, u, mesh.face_vertex_ancestor(fkey, u), v)
elif case == 2:
# remove triangular face and merge the two boundary vertices
# due to singularities at the same location
polyline = Polyline(self.decomposition_polyline(*map(lambda x: geometric_key(mesh.vertex_coordinates(x)), boundary_vertices)))
point = polyline.point(t = .5, snap = True)
new_vkey = mesh.add_vertex(attr_dict = {'x': point.x, 'y': point.y , 'z': point.z})
# modify triangular face
mesh.delete_face(fkey)
# modify adjacent faces
for old_vkey in boundary_vertices:
mesh_substitute_vertex_in_faces(mesh, old_vkey, new_vkey, mesh.vertex_faces(old_vkey))
mesh.delete_vertex(old_vkey)
to_move = {}
# give some length to the new edge
for edge in mesh.edges():
threshold = 1e-6
if mesh.edge_length(*edge) < threshold:
for vkey in edge:
xyz = centroid_points([mesh.vertex_coordinates(nbr) for nbr in mesh.vertex_neighbors(vkey)])
xyz0 = mesh.vertex_coordinates(vkey)
to_move[vkey] = [0.1 * (a - a0) for a, a0 in zip(xyz, xyz0)]
for vkey, xyz in to_move.items():
attr = mesh.vertex[vkey]
attr['x'] += xyz[0]
attr['y'] += xyz[1]
attr['z'] += xyz[2]
def test_insert_vertex_on_edge(mesh_0):
mesh_insert_vertex_on_edge(mesh_0, 0, 1)
assert len(mesh_0.face_vertices(0)) == 4
assert len(mesh_0.face_vertices(1)) == 4
assert mesh_0.face_vertex_descendant(0, 0) == 5
assert mesh_0.face_vertex_descendant(1, 1) == 5
mesh_insert_vertex_on_edge(mesh_0, 0, 2, 4)
assert len(mesh_0.face_vertices(0)) == 5
assert mesh_0.face_vertex_descendant(0, 2) == 4