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got cc working

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Stephen M. McQuay 2012-05-18 00:59:04 -06:00
parent dd6148ef52
commit 7d89a5778b
1 changed files with 63 additions and 43 deletions
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106
surf/subd/cc.py
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@ -5,46 +5,45 @@ from surf.geometry import PolygonMesh, centroid
def refine(mesh):
new_vertices = list(mesh.vertices)
# this can be used to both get to fvid in new_vertices and to offest
# mesh.faces to be dealing with the fvid generated from that face
f_vert_offset = len(new_vertices)
edge_vids_for_face = defaultdict(list)
face_ids_for_v = defaultdict(list)
# this doesn't need to be calculated, but it is conceptually convenient to
# have along the way. Alternatively one could get this by doing a:
# >>> [e + e_vert_offset for e in mesh.edges_for_face[fvid]
# (fvid for all faces)
evid_for_fvid = defaultdict(list)
# TODO: not completely populated yet:
new_edges = []
# TODO: must be populated:
new_faces = []
# For each face, add a face point
for cur_face_id, cur_face in enumerate(mesh.faces):
# Set each face point to be the centroid of all original points for the
# respective face.
# For each face, add a face Vertex
for old_fid, old_face in enumerate(mesh.faces):
# Set each face Vertex to be the centroid of all original Vertices for
# the respective face.
# here we have already created a list that is a copy of the original
# verts. we append the new face points to that same list, and simply
# keep track of offsets into the new vert list ... see e_vert_offset
# below
new_face_point = mesh.centroid(cur_face)
new_vertices.append(new_face_point)
for i in cur_face:
face_ids_for_v[i].append(cur_face_id)
# verts. we append the new face Vertices to that same list, and simply
# keep track of offsets into the new vert list ... see f_vert_offset
# above and e_vert_offset below
new_face_vertex = mesh.centroid(old_face)
new_vertices.append(new_face_vertex)
# edge verts will be new_vertices[e_vert_offset:]. Also, this can be used
# to both get to evid in new_vertices and to offest mesh.edges to be
# dealing with the evid generated from that edge
e_vert_offset = len(new_vertices)
# For each edge, add an edge point.
for old_edge_id, old_edge in enumerate(mesh.edges):
# make mapping from edge -> new_face_vert for later
old_face_ids_for_old_edge = mesh.faces_for_edge[old_edge_id]
for fid in old_face_ids_for_old_edge:
edge_vids_for_face[fid].append(old_edge_id)
# For each edge, add an edge Vertex.
for old_eid, old_edge in enumerate(mesh.edges):
tmp_verts = []
# Set each edge point to be the average of the two neighbouring, (very
# recently calculated) face points ...
# Set each edge Vertex to be the average of the two neighbouring, (very
# recently calculated) face Vertices ...
tmp_verts.extend([new_vertices[f + f_vert_offset]
for f in old_face_ids_for_old_edge])
for f in mesh.faces_for_edge[old_eid]])
# ... and its two original endpoints.
tmp_verts.extend([mesh.vertices[vid] for vid in old_edge])
@ -52,25 +51,23 @@ def refine(mesh):
# centroid == average
new_vertices.append(centroid(tmp_verts))
# For each face point, add an edge connecting the new face point to each
# new edge point
new_face_vert_ids = new_vertices[f_vert_offset:e_vert_offset]
for trunc_vid in xrange(len(new_face_vert_ids)):
overall_vid = f_vert_offset + trunc_vid
for edge_vid in edge_vids_for_face[trunc_vid]:
new_edges.append([edge_vid, overall_vid])
# make mapping from evid -> fvid for later
for old_fid in mesh.faces_for_edge[old_eid]:
fvid = old_fid + f_vert_offset
evid = old_eid + e_vert_offset
evid_for_fvid[fvid].append(evid)
# For each original point P, move the original point to a new location
# For each original Vertex P, move the original Vertex to a new location
# Here we mimic the F, R, and P spelling in the wiki article
for old_vid in xrange(f_vert_offset):
# take the average F of all n face points for faces touching P ...
# take the average F of all n face Vertices for faces touching P ...
F_verts = []
for old_fid in mesh.faces_for_vert[old_vid]:
F_verts.append(new_vertices[f_vert_offset + old_fid])
F = centroid(F_verts)
# and take the average R of all n edge midpoints for edges touching P
# wiki is wrong ... it should be the edge points, not midpoints ...
# and take the average R of all n new edge Vertices for edges adjacent
# to P
edges = [mesh.edges[eid] for eid in mesh.edges_for_vert[old_vid]]
e_verts = []
for edge in edges:
@ -78,16 +75,39 @@ def refine(mesh):
R = centroid(e_verts)
# where each edge midpoint is the average of its two endpoint vertices.
# **Move** each original point to the point (or add it to new_verts)
# *Move* each original point to the point (or replace it in new_verts)
new_vertex_point = (F + 2 * R
+ (len(edges) - 3) * new_vertices[old_vid]
+ (len(edges) - 3) * new_vertices[old_vid]
) / len(edges)
new_vertices[old_vid] = new_vertex_point
# Connect each new Vertex point to the new edge points of all original
# edges incident on the original vertex.
for eid in mesh.edges_for_vert[old_vid]:
new_edges.append([old_vid, eid])
# Connect each new Vertex point (with original id) to the new edge
# points of all original edges incident on the original vertex.
for old_eid in mesh.edges_for_vert[old_vid]:
new_edges.append([old_vid, old_eid + e_vert_offset])
# For each face point, add an edge connecting the new face point to each
# new edge point
for fvid, evids in evid_for_fvid.iteritems():
for evid in evids:
new_edges.append([fvid, evid])
# to define new faces need to know the following for each new face:
for fvid in xrange(f_vert_offset, e_vert_offset):
# new face_vid (1 vid)
# vid connected to fvid (iterate over, use 1 vid periteration)
connected_vids = mesh.faces[fvid - f_vert_offset]
evids_for_current_face = evid_for_fvid[fvid]
for connected_vid in connected_vids:
# evid connected to both the vid and the fvid (2 vids)
evids_for_vid = [e + e_vert_offset for e in
mesh.edges_for_vert[connected_vid]]
assert len(evids_for_vid) == 3
common_ids = list(set(evids_for_vid) & set(evids_for_current_face))
assert len(common_ids) == 2
# then connect the (4) vids together ...
new_faces.append([fvid, common_ids[0], connected_vid, common_ids[1]])
return PolygonMesh(vertices=new_vertices, edges=new_edges, faces=new_faces)