[#18694] Added support for Wavefront OBJ groups for both the import and export scripts

from Paolo Ciccone (pciccone) 

Im not that keen on this functionality since vertex groups in blender are for weight painting and OBJ's groups are more like sub-objects, The conversion between these is a poor approximation (one vertex group per face).
But this is still useful for using blender with poser so accepting these 2 patches.

Made some changes from the patch
*Export*
- vgroup off by default, since this is mainly useful for corner cases
- findVertexGroupName() - changed how exporting selects a vertex group for a face, use the highest combind weight for each group instead of  the number of checking how many times the verts are in a group because they could have a zero weight.
- findVertexGroupName() - would fail if a faces verts were not in any groups, now return a (null) group
- Allow modifiers to export with vgroups

*Import*
- disable by default
- ignore (null) groups
- fixed a problem where the patch broke SPLIT_GROUPS
- move the group definition out of global namespace, breaks importing as a module.

--- Patch submission info
The import/export scripts included with Blender 2.48 don't save/preserve groups defined in OBJ file. This presents a
couple of issues: users loading an obj file with groups are not able to use a rather important set of data. When the
file is then saved the groups are lost bringing up both the issue of data loss and loss of functionality as groups are
used for rigging and morph target creation for Poser/DAZ Studio and all compatible applications. Of course other
animation/modeling packages that use OBJ files might be affected.

The solution that I present here simply patches the excellent python scripts written by Campbell Barton and Jiri Hnidek.
The new code implements the preservation of groups by creating Blender vertex groups during import and by re-writing
those groups in the OBJ file during export. Of course group ownership is idetermined at the face/polygon level and not
at the vertex level.

This rather simple solution makes Blender instantly one of the better tools to create Poser Morph targets (Full Body
Morphs) and conforming figures and clothing.  Of course it's also adding a more complete support for the whole OBJ spec.

The patches are fitting well inside the established logic, have a minimal impact and are totally transparent to the
user. See the attached video (about 7 minutes long) for more details.

I noticed that the original scripts are formatted with tabs. I think it would be a good idea to follow the standard
Python recommendation and convert the scripts to use spaces. I didn't want to do it on my side as it would generate
a patch that replaces the whole file, not something that I wanted to do with my first submission :) But it would help
if people with access to SVN could do it.

Here is a short video that demonstrates the updates:
http://www.paolociccone.com/blender_obj_scripts.html

Cheers!
----
This commit is contained in:
2009-05-13 00:20:14 +00:00
parent 9147124ac2
commit c19baf85cc
2 changed files with 133 additions and 41 deletions

View File

@@ -7,9 +7,9 @@ Group: 'Export'
Tooltip: 'Save a Wavefront OBJ File'
"""
__author__ = "Campbell Barton, Jiri Hnidek"
__author__ = "Campbell Barton, Jiri Hnidek, Paolo Ciccone"
__url__ = ['http://wiki.blender.org/index.php/Scripts/Manual/Export/wavefront_obj', 'www.blender.org', 'blenderartists.org']
__version__ = "1.2"
__version__ = "1.21"
__bpydoc__ = """\
This script is an exporter to OBJ file format.
@@ -185,7 +185,8 @@ def write(filename, objects,\
EXPORT_TRI=False, EXPORT_EDGES=False, EXPORT_NORMALS=False, EXPORT_NORMALS_HQ=False,\
EXPORT_UV=True, EXPORT_MTL=True, EXPORT_COPY_IMAGES=False,\
EXPORT_APPLY_MODIFIERS=True, EXPORT_ROTX90=True, EXPORT_BLEN_OBS=True,\
EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=False):
EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=False,\
EXPORT_POLYGROUPS=False):
'''
Basic write function. The context and options must be alredy set
This can be accessed externaly
@@ -199,6 +200,29 @@ EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=Fal
def veckey2d(v):
return round(v.x, 6), round(v.y, 6)
def findVertexGroupName(face, vWeightMap):
"""
Searches the vertexDict to see what groups is assigned to a given face.
We use a frequency system in order to sort out the name because a given vetex can
belong to two or more groups at the same time. To find the right name for the face
we list all the possible vertex group names with their frequency and then sort by
frequency in descend order. The top element is the one shared by the highest number
of vertices is the face's group
"""
weightDict = {}
for vert in face:
vWeights = vWeightMap[vert.index]
for vGroupName, weight in vWeights:
weightDict[vGroupName] = weightDict.get(vGroupName, 0) + weight
if weightDict:
alist = [(weight,vGroupName) for vGroupName, weight in weightDict.iteritems()] # sort least to greatest amount of weight
alist.sort()
return(alist[-1][1]) # highest value last
else:
return '(null)'
print 'OBJ Export path: "%s"' % filename
temp_mesh_name = '~tmp-mesh'
@@ -239,12 +263,12 @@ EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=Fal
globalNormals = {}
# Get all meshs
# Get all meshes
for ob_main in objects:
for ob, ob_mat in BPyObject.getDerivedObjects(ob_main):
# Will work for non meshes now! :)
# getMeshFromObject(ob, container_mesh=None, apply_modifiers=True, vgroups=True, scn=None)
me= BPyMesh.getMeshFromObject(ob, containerMesh, EXPORT_APPLY_MODIFIERS, False, scn)
me= BPyMesh.getMeshFromObject(ob, containerMesh, EXPORT_APPLY_MODIFIERS, EXPORT_POLYGROUPS, scn)
if not me:
continue
@@ -397,6 +421,17 @@ EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=Fal
if not faceuv:
f_image = None
if EXPORT_POLYGROUPS:
# Retrieve the list of vertex groups
vertGroupNames = me.getVertGroupNames()
currentVGroup = ''
# Create a dictionary keyed by face id and listing, for each vertex, the vertex groups it belongs to
vgroupsMap = [[] for _i in xrange(len(me.verts))]
for vertexGroupName in vertGroupNames:
for vIdx, vWeight in me.getVertsFromGroup(vertexGroupName, 1):
vgroupsMap[vIdx].append((vertexGroupName, vWeight))
for f_index, f in enumerate(faces):
f_v= f.v
f_smooth= f.smooth
@@ -411,9 +446,18 @@ EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=Fal
else:
key = materialNames[f_mat], None # No image, use None instead.
# Write the vertex group
if EXPORT_POLYGROUPS:
if vertGroupNames:
# find what vertext group the face belongs to
theVGroup = findVertexGroupName(f,vgroupsMap)
if theVGroup != currentVGroup:
currentVGroup = theVGroup
file.write('g %s\n' % theVGroup)
# CHECK FOR CONTEXT SWITCH
if key == contextMat:
pass # Context alredy switched, dont do anythoing
pass # Context alredy switched, dont do anything
else:
if key[0] == None and key[1] == None:
# Write a null material, since we know the context has changed.
@@ -438,6 +482,7 @@ EXPORT_GROUP_BY_OB=False, EXPORT_GROUP_BY_MAT=False, EXPORT_KEEP_VERT_ORDER=Fal
if EXPORT_GROUP_BY_MAT:
file.write('g %s_%s_%s\n' % (fixName(ob.name), fixName(ob.getData(1)), mat_data[0]) ) # can be mat_image or (null)
file.write('usemtl %s\n' % mat_data[0]) # can be mat_image or (null)
contextMat = key
@@ -539,7 +584,8 @@ def write_ui(filename):
EXPORT_NORMALS, EXPORT_NORMALS_HQ, EXPORT_UV,\
EXPORT_MTL, EXPORT_SEL_ONLY, EXPORT_ALL_SCENES,\
EXPORT_ANIMATION, EXPORT_COPY_IMAGES, EXPORT_BLEN_OBS,\
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER,\
EXPORT_POLYGROUPS
EXPORT_APPLY_MODIFIERS = Draw.Create(0)
EXPORT_ROTX90 = Draw.Create(1)
@@ -557,6 +603,8 @@ def write_ui(filename):
EXPORT_GROUP_BY_OB = Draw.Create(0)
EXPORT_GROUP_BY_MAT = Draw.Create(0)
EXPORT_KEEP_VERT_ORDER = Draw.Create(1)
EXPORT_POLYGROUPS = Draw.Create(0)
# Old UI
'''
@@ -607,7 +655,7 @@ def write_ui(filename):
GLOBALS['EVENT'] = e
def do_split(e,v):
global EXPORT_BLEN_OBS, EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_APPLY_MODIFIERS, KEEP_VERT_ORDER
global EXPORT_BLEN_OBS, EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_APPLY_MODIFIERS, KEEP_VERT_ORDER, EXPORT_POLYGROUPS
if EXPORT_BLEN_OBS.val or EXPORT_GROUP_BY_OB.val or EXPORT_GROUP_BY_MAT.val or EXPORT_APPLY_MODIFIERS.val:
EXPORT_KEEP_VERT_ORDER.val = 0
else:
@@ -621,6 +669,7 @@ def write_ui(filename):
if not (EXPORT_BLEN_OBS.val or EXPORT_GROUP_BY_OB.val or EXPORT_GROUP_BY_MAT.val or EXPORT_APPLY_MODIFIERS.val):
EXPORT_KEEP_VERT_ORDER.val = 1
def do_help(e,v):
url = __url__[0]
print 'Trying to open web browser with documentation at this address...'
@@ -637,43 +686,45 @@ def write_ui(filename):
# Center based on overall pup size
ui_x -= 165
ui_y -= 110
ui_y -= 140
global EXPORT_APPLY_MODIFIERS, EXPORT_ROTX90, EXPORT_TRI, EXPORT_EDGES,\
EXPORT_NORMALS, EXPORT_NORMALS_HQ, EXPORT_UV,\
EXPORT_MTL, EXPORT_SEL_ONLY, EXPORT_ALL_SCENES,\
EXPORT_ANIMATION, EXPORT_COPY_IMAGES, EXPORT_BLEN_OBS,\
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER,\
EXPORT_POLYGROUPS
Draw.Label('Context...', ui_x+9, ui_y+209, 220, 20)
Draw.Label('Context...', ui_x+9, ui_y+239, 220, 20)
Draw.BeginAlign()
EXPORT_SEL_ONLY = Draw.Toggle('Selection Only', EVENT_NONE, ui_x+9, ui_y+189, 110, 20, EXPORT_SEL_ONLY.val, 'Only export objects in visible selection. Else export whole scene.')
EXPORT_ALL_SCENES = Draw.Toggle('All Scenes', EVENT_NONE, ui_x+119, ui_y+189, 110, 20, EXPORT_ALL_SCENES.val, 'Each scene as a separate OBJ file.')
EXPORT_ANIMATION = Draw.Toggle('Animation', EVENT_NONE, ui_x+229, ui_y+189, 110, 20, EXPORT_ANIMATION.val, 'Each frame as a numbered OBJ file.')
EXPORT_SEL_ONLY = Draw.Toggle('Selection Only', EVENT_NONE, ui_x+9, ui_y+219, 110, 20, EXPORT_SEL_ONLY.val, 'Only export objects in visible selection. Else export whole scene.')
EXPORT_ALL_SCENES = Draw.Toggle('All Scenes', EVENT_NONE, ui_x+119, ui_y+219, 110, 20, EXPORT_ALL_SCENES.val, 'Each scene as a separate OBJ file.')
EXPORT_ANIMATION = Draw.Toggle('Animation', EVENT_NONE, ui_x+229, ui_y+219, 110, 20, EXPORT_ANIMATION.val, 'Each frame as a numbered OBJ file.')
Draw.EndAlign()
Draw.Label('Output Options...', ui_x+9, ui_y+159, 220, 20)
Draw.Label('Output Options...', ui_x+9, ui_y+189, 220, 20)
Draw.BeginAlign()
EXPORT_APPLY_MODIFIERS = Draw.Toggle('Apply Modifiers', EVENT_REDRAW, ui_x+9, ui_y+140, 110, 20, EXPORT_APPLY_MODIFIERS.val, 'Use transformed mesh data from each object. May break vert order for morph targets.', do_split)
EXPORT_ROTX90 = Draw.Toggle('Rotate X90', EVENT_NONE, ui_x+119, ui_y+140, 110, 20, EXPORT_ROTX90.val, 'Rotate on export so Blenders UP is translated into OBJs UP')
EXPORT_COPY_IMAGES = Draw.Toggle('Copy Images', EVENT_NONE, ui_x+229, ui_y+140, 110, 20, EXPORT_COPY_IMAGES.val, 'Copy image files to the export directory, never overwrite.')
EXPORT_APPLY_MODIFIERS = Draw.Toggle('Apply Modifiers', EVENT_REDRAW, ui_x+9, ui_y+170, 110, 20, EXPORT_APPLY_MODIFIERS.val, 'Use transformed mesh data from each object. May break vert order for morph targets.', do_split)
EXPORT_ROTX90 = Draw.Toggle('Rotate X90', EVENT_NONE, ui_x+119, ui_y+170, 110, 20, EXPORT_ROTX90.val, 'Rotate on export so Blenders UP is translated into OBJs UP')
EXPORT_COPY_IMAGES = Draw.Toggle('Copy Images', EVENT_NONE, ui_x+229, ui_y+170, 110, 20, EXPORT_COPY_IMAGES.val, 'Copy image files to the export directory, never overwrite.')
Draw.EndAlign()
Draw.Label('Export...', ui_x+9, ui_y+109, 220, 20)
Draw.Label('Export...', ui_x+9, ui_y+139, 220, 20)
Draw.BeginAlign()
EXPORT_EDGES = Draw.Toggle('Edges', EVENT_NONE, ui_x+9, ui_y+90, 50, 20, EXPORT_EDGES.val, 'Edges not connected to faces.')
EXPORT_TRI = Draw.Toggle('Triangulate', EVENT_NONE, ui_x+59, ui_y+90, 70, 20, EXPORT_TRI.val, 'Triangulate quads.')
EXPORT_EDGES = Draw.Toggle('Edges', EVENT_NONE, ui_x+9, ui_y+120, 50, 20, EXPORT_EDGES.val, 'Edges not connected to faces.')
EXPORT_TRI = Draw.Toggle('Triangulate', EVENT_NONE, ui_x+59, ui_y+120, 70, 20, EXPORT_TRI.val, 'Triangulate quads.')
Draw.EndAlign()
Draw.BeginAlign()
EXPORT_MTL = Draw.Toggle('Materials', EVENT_NONE, ui_x+139, ui_y+90, 70, 20, EXPORT_MTL.val, 'Write a separate MTL file with the OBJ.')
EXPORT_UV = Draw.Toggle('UVs', EVENT_NONE, ui_x+209, ui_y+90, 31, 20, EXPORT_UV.val, 'Export texface UV coords.')
EXPORT_MTL = Draw.Toggle('Materials', EVENT_NONE, ui_x+139, ui_y+120, 70, 20, EXPORT_MTL.val, 'Write a separate MTL file with the OBJ.')
EXPORT_UV = Draw.Toggle('UVs', EVENT_NONE, ui_x+209, ui_y+120, 31, 20, EXPORT_UV.val, 'Export texface UV coords.')
Draw.EndAlign()
Draw.BeginAlign()
EXPORT_NORMALS = Draw.Toggle('Normals', EVENT_NONE, ui_x+250, ui_y+90, 59, 20, EXPORT_NORMALS.val, 'Export vertex normal data (Ignored on import).')
EXPORT_NORMALS_HQ = Draw.Toggle('HQ', EVENT_NONE, ui_x+309, ui_y+90, 31, 20, EXPORT_NORMALS_HQ.val, 'Calculate high quality normals for rendering.')
EXPORT_NORMALS = Draw.Toggle('Normals', EVENT_NONE, ui_x+250, ui_y+120, 59, 20, EXPORT_NORMALS.val, 'Export vertex normal data (Ignored on import).')
EXPORT_NORMALS_HQ = Draw.Toggle('HQ', EVENT_NONE, ui_x+309, ui_y+120, 31, 20, EXPORT_NORMALS_HQ.val, 'Calculate high quality normals for rendering.')
Draw.EndAlign()
EXPORT_POLYGROUPS = Draw.Toggle('Polygroups', EVENT_REDRAW, ui_x+9, ui_y+95, 120, 20, EXPORT_POLYGROUPS.val, 'Export vertex groups as OBJ groups (one group per face approximation).')
Draw.Label('Blender Objects as OBJ:', ui_x+9, ui_y+59, 220, 20)
@@ -727,7 +778,7 @@ def write_ui(filename):
EXPORT_GROUP_BY_OB = EXPORT_GROUP_BY_OB.val
EXPORT_GROUP_BY_MAT = EXPORT_GROUP_BY_MAT.val
EXPORT_KEEP_VERT_ORDER = EXPORT_KEEP_VERT_ORDER.val
EXPORT_POLYGROUPS = EXPORT_POLYGROUPS.val
base_name, ext = splitExt(filename)
@@ -776,7 +827,8 @@ def write_ui(filename):
EXPORT_NORMALS_HQ, EXPORT_UV, EXPORT_MTL,\
EXPORT_COPY_IMAGES, EXPORT_APPLY_MODIFIERS,\
EXPORT_ROTX90, EXPORT_BLEN_OBS,\
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER)
EXPORT_GROUP_BY_OB, EXPORT_GROUP_BY_MAT, EXPORT_KEEP_VERT_ORDER,\
EXPORT_POLYGROUPS)
Blender.Set('curframe', orig_frame)