simplify to compatible with other codes

Author: GeneKao

src/compas/datastructures/mesh/duality.py

@@ -11,7 +11,7 @@
 PI2 = 2.0 * pi
 
 
-def mesh_dual(mesh, cls=None, include_boundary=False, preserve_boundary_vertices=False, preserve_corner_vertices=False):
+def mesh_dual(mesh, cls=None, include_boundary=False):
     """Construct the dual of a mesh.
 
     Parameters
@@ -24,12 +24,6 @@ def mesh_dual(mesh, cls=None, include_boundary=False, preserve_boundary_vertices
     include_boundary: str, optional
         Whether to include boundary faces for the dual mesh
         Default mode is False, don't create faces on boundaries.
-    preserve_boundary_vertices: str, optional
-        Whether to preserve boundary vertices from the original mesh
-        Default mode is False, include the boundary without the original vertices.
-    preserve_corner_vertices: str, optional
-        Whether to preserve corner vertices (only connect to one face) from the original mesh
-        Default mode is False, include the boundary with the original vertices only on corners.
 
     Returns
     -------
@@ -46,83 +40,67 @@ def mesh_dual(mesh, cls=None, include_boundary=False, preserve_boundary_vertices
     >>> mesh.delete_face(7)
     >>> mesh.quads_to_triangles()
     >>> mesh = mesh.subdivide('corner')
-    >>> dual = mesh.dual(include_boundary=True, preserve_boundary_vertices=True, preserve_corner_vertices=False)
+    >>> dual = mesh.dual(include_boundary=True)
 
     """
     if not cls:
         cls = type(mesh)
 
     dual = cls()
 
-    mesh.flip_cycles()
-
     face_centroid = {face: mesh.face_centroid(face) for face in mesh.faces()}
-    outer = list(flatten(mesh.vertices_on_boundaries()))
+    outer = set(flatten(mesh.vertices_on_boundaries()))
+    inner = list(set(mesh.vertices()) - outer)
     vertex_xyz = {}
     face_vertices = {}
-    edge_vertex = {}
 
-    # safe guarded if face index is arbitrary, random, not starting from 0
-    num_faces = max(max(list(mesh.faces())) + 1, mesh.number_of_faces())
-    for vertex in mesh.vertices():
+    for vertex in inner:
         faces = mesh.vertex_faces(vertex, ordered=True)
         for face in faces:
             if face not in vertex_xyz:
                 vertex_xyz[face] = face_centroid[face]
         face_vertices[vertex] = faces
 
-        if not include_boundary:
-            continue
-
-        if vertex not in outer or len(faces) < 1:
-            continue
-
-        boundary_fids = faces[:]
-        current_face = vertex
-        corner_count = 0
-        edge_count = 0
-
-        for nbr_vertex in reversed(mesh.vertex_neighbors(vertex, ordered=True)):
-
-            if not mesh.is_edge_on_boundary(vertex, nbr_vertex):
-                continue
-            pt = mesh.edge_midpoint(vertex, nbr_vertex)
-
-            if num_faces not in vertex_xyz and len(faces) == 1 and corner_count == 0 and (preserve_corner_vertices or preserve_boundary_vertices):
-                vertex_xyz[num_faces] = mesh.vertex_coordinates(vertex)
-                current_face = num_faces
-                num_faces += 1
-                corner_count += 1
-
-            if num_faces not in vertex_xyz and len(faces) != 1 and edge_count == 0 and preserve_boundary_vertices:
-                vertex_xyz[num_faces] = mesh.vertex_coordinates(vertex)
-                current_face = num_faces
-                num_faces += 1
-                edge_count += 1
-
-            if num_faces not in vertex_xyz and ((vertex, nbr_vertex) not in edge_vertex and
-                                                (nbr_vertex, vertex) not in edge_vertex):
-
-                vertex_xyz[num_faces] = pt
-                edge_vertex[vertex, nbr_vertex] = edge_vertex[nbr_vertex, vertex] = num_faces
-                boundary_fids.append(num_faces)
-                num_faces += 1
-            else:
-                boundary_fids.append(edge_vertex[vertex, nbr_vertex])
-
-        if vertex in outer and len(faces) == 1 and (preserve_corner_vertices or preserve_boundary_vertices):
-            boundary_fids.insert(len(faces) + 1, current_face)
-
-        if vertex in outer and len(faces) != 1 and preserve_boundary_vertices:
-            boundary_fids.insert(len(faces) + 1, current_face)
-
-        face_vertices[vertex] = boundary_fids
-
     for vertex in vertex_xyz:
         x, y, z = vertex_xyz[vertex]
         dual.add_vertex(vertex, x=x, y=y, z=z)
 
     for face in face_vertices:
         dual.add_face(face_vertices[face], fkey=face)
 
+    if not include_boundary:
+        return dual
+
+    for boundary in mesh.faces_on_boundaries():
+        for face in boundary:
+            if not dual.has_vertex(face):
+                x, y, z = face_centroid[face]
+                dual.add_vertex(key=face, x=x, y=y, z=z)
+
+    edge_vertex = {}
+    for boundary in mesh.edges_on_boundaries():
+        for u, v in boundary:
+            x, y, z = mesh.edge_midpoint(u, v)
+            edge_vertex[u, v] = edge_vertex[v, u] = dual.add_vertex(x=x, y=y, z=z)
+
+    vertex_vertex = {}
+    for boundary in mesh.vertices_on_boundaries():
+        if boundary[0] == boundary[-1]:
+            boundary = boundary[:-1]
+        for vertex in boundary:
+            x, y, z = mesh.vertex_coordinates(vertex)
+            vertex_vertex[vertex] = dual.add_vertex(x=x, y=y, z=z)
+
+    for boundary in mesh.vertices_on_boundaries():
+        if boundary[0] == boundary[-1]:
+            boundary = boundary[:-1]
+        for vertex in boundary:
+            vertices = [vertex_vertex[vertex]]
+            nbrs = mesh.vertex_neighbors(vertex, ordered=True)[::-1]
+            vertices.append(edge_vertex[vertex, nbrs[0]])
+            for nbr in nbrs[:-1]:
+                vertices.append(mesh.halfedge_face(vertex, nbr))
+            vertices.append(edge_vertex[vertex, nbrs[-1]])
+            dual.add_face(vertices[::-1])
+
     return dual