[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [35202] trunk/blender/release/scripts/ modules/mesh_utils.py: port of function from 2.4x's BPyMesh.py thanks to ' merlin_' on IRC.

[Campbell Barton]

Revision: 35202
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=35202
Author:   campbellbarton
Date:     2011-02-26 16:13:14 +0000 (Sat, 26 Feb 2011)
Log Message:
-----------
port of function from 2.4x's BPyMesh.py thanks to 'merlin_' on IRC.

Added Paths:
-----------
    trunk/blender/release/scripts/modules/mesh_utils.py

Added: trunk/blender/release/scripts/modules/mesh_utils.py
===================================================================
--- trunk/blender/release/scripts/modules/mesh_utils.py	                        (rev 0)
+++ trunk/blender/release/scripts/modules/mesh_utils.py	2011-02-26 16:13:14 UTC (rev 35202)
@@ -0,0 +1,69 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+# <pep8 compliant>
+
+
+def mesh_linked_faces(me):
+    '''
+    Splits the mesh into connected parts,
+    these parts are returned as lists of faces.
+    used for seperating cubes from other mesh elements in the 1 mesh
+    '''
+
+    # Build vert face connectivity
+    vert_faces = [[] for i in range(len(mesh.vertices))]
+    for f in mesh.faces:
+        for v in f.vertices:
+            vert_faces[v].append(f)
+
+    # sort faces into connectivity groups
+    face_groups = [[f] for f in mesh.faces]
+    face_mapping = list(range(len(mesh.faces)))  # map old, new face location
+
+    # Now clump faces iterativly
+    ok = True
+    while ok:
+        ok = False
+
+        for i, f in enumerate(mesh.faces):
+            mapped_index = face_mapping[f.index]
+            mapped_group = face_groups[mapped_index]
+
+            for v in f.vertices:
+                for nxt_f in vert_faces[v]:
+                    if nxt_f != f:
+                        nxt_mapped_index = face_mapping[nxt_f.index]
+
+                        # We are not a part of the same group
+                        if mapped_index != nxt_mapped_index:
+                            ok = True
+
+                            # Assign mapping to this group so they all map to this group
+                            for grp_f in face_groups[nxt_mapped_index]:
+                                face_mapping[grp_f.index] = mapped_index
+
+                            # Move faces into this group
+                            mapped_group.extend(face_groups[nxt_mapped_index])
+
+                            # remove reference to the list
+                            face_groups[nxt_mapped_index] = None
+
+    # return all face groups that are not null
+    # this is all the faces that are connected in their own lists.
+    return [fg for fg in face_groups if fg]