#!BPY
"""
Name: 'Clean meshes'
Blender: 228
Group: 'Mesh'
Tooltip: 'Clean unused data from all selected mesh objects.'
"""
from Blender import *
from Blender.Mathutils import TriangleArea

import Blender
import BPyMesh
reload(BPyMesh)
dict2MeshWeight= BPyMesh.dict2MeshWeight
meshWeight2Dict= BPyMesh.meshWeight2Dict

def rem_free_verts(me):
	vert_users= [0] * len(me.verts)
	for f in me.faces:
		for v in f.v:
			vert_users[v.index]+=1
	
	for e in me.edges:
		for v in e: # loop on edge verts
			vert_users[v.index]+=1
	
	verts_free= []
	for i, users in enumerate(vert_users):
		if not users:
			verts_free.append(i)
	
	if verts_free:
		pass
		me.verts.delete(verts_free)
	return len(verts_free)
	
def rem_free_edges(me, limit=None):
	''' Only remove based on limit if a limit is set, else remove all '''
	def sortPair(a,b):
		return min(a,b), max(a,b)
	
	edgeDict= {} # will use a set when python 2.4 is standard.
	
	for f in me.faces:
		v= f.v
		for i in xrange(len(v)):
			edgeDict[sortPair(v[i].index, v[i-1].index)]= None
	
	edges_free= []
	for e in me.edges:
		if not edgeDict.has_key(sortPair(e.v1.index, e.v2.index)):
			edges_free.append(e)
	
	if limit != None:
		edges_free= [e for e in edges_free if (e.v1.co-e.v2.co).length <= limit]
	
	me.edges.delete(edges_free)
	return len(edges_free)

def rem_area_faces(me, limit=0.001):
	''' Faces that have an area below the limit '''
	rem_faces= [f for f in me.faces if f.area <= limit]
	if rem_faces:
		me.faces.delete( 0, rem_faces )
	return len(rem_faces)

def rem_perimeter_faces(me, limit=0.001):
	''' Faces whos combine edge length is below the limit '''
	def faceEdLen(f):
		v= f.v
		if len(v) == 3:
			return\
			(v[0].co-v[1].co).length +\
			(v[1].co-v[2].co).length +\
			(v[2].co-v[0].co).length
		else: # 4
			return\
			(v[0].co-v[1].co).length +\
			(v[1].co-v[2].co).length +\
			(v[2].co-v[3].co).length +\
			(v[3].co-v[0].co).length
	rem_faces= [f for f in me.faces if faceEdLen(f) <= limit]
	if rem_faces:
		me.faces.delete( 0, rem_faces )
	return len(rem_faces)

def rem_unused_materials(me):
	materials= me.materials
	len_materials= len(materials)
	if len_materials < 2:
		return 0
		
	rem_materials= 0
	
	material_users= dict( [(i,0) for i in xrange(len_materials)] )
	
	for f in me.faces:
		# Make sure the face index isnt too big. this happens sometimes.
		if f.mat >= len_materials:
			f.mat=0
		material_users[f.mat] += 1
	
	mat_idx_subtract= 0
	reindex_mapping= dict( [(i,0) for i in xrange(len_materials)] )
	i= len_materials
	while i:
		i-=1
		
		if material_users[i] == 0:
			mat_idx_subtract+=1
			reindex_mapping[i]= mat_idx_subtract
			materials.pop(i)
			rem_materials+=1
	
	for f in me.faces:
		f.mat= f.mat - reindex_mapping[f.mat]
	
	me.materials= materials
	return rem_materials


def rem_free_groups(me, groupNames, vWeightDict):
	''' cound how many vert users a group has and remove unsued groups '''
	rem_groups		= 0
	groupUserDict= dict([(group,0) for group in groupNames])
	
	for vertexWeight in vWeightDict:
		for group, weight in vertexWeight.iteritems():
			groupUserDict[group] += 1
	
	i=len(groupNames)
	while i:
		i-=1
		group= groupNames[i]
		if groupUserDict[group] == 0:
			del groupNames[i]
			print '\tremoving, vgroup', group
			rem_groups+=1
	return rem_groups

def rem_zero_weights(me, limit, groupNames, vWeightDict):
	''' remove verts from a group when their weight is zero.'''
	rem_vweight_count= 0
	for vertexWeight in vWeightDict:
		items= vertexWeight.items()
		for group, weight in items:
			if weight < limit:
				del vertexWeight[group]
				rem_vweight_count+= 1

	return rem_vweight_count

	
def normalize_vweight(me, groupNames, vWeightDict):
	for vertexWeight in vWeightDict:
		unit= 0.0
		for group, weight in vertexWeight.iteritems():
			unit+= weight
		
		if unit != 1.0 and unit != 0.0:
			for group, weight in vertexWeight.iteritems():
				vertexWeight[group]= weight/unit



def main():	
	scn= Scene.GetCurrent()
	obsel= Object.GetSelected()
	actob= scn.getActiveObject()
	
	is_editmode= Window.EditMode()
	
	# Edit mode object is not active, add it to the list.
	if is_editmode and (not actob.sel):
		obsel.append(actob)
	
	
	#====================================#
	# Popup menu to select the functions #
	#====================================#
	
	CLEAN_ALL_DATA= Draw.Create(0)
	CLEAN_VERTS_FREE= Draw.Create(1)
	CLEAN_EDGE_NOFACE= Draw.Create(0)
	CLEAN_EDGE_SMALL= Draw.Create(0)
	CLEAN_FACE_PERIMETER= Draw.Create(0)
	CLEAN_FACE_SMALL= Draw.Create(0)
	
	CLEAN_MATERIALS= Draw.Create(0)
	CLEAN_GROUP= Draw.Create(0)
	CLEAN_VWEIGHT= Draw.Create(0)
	CLEAN_WEIGHT_NORMALIZE= Draw.Create(0)
	limit= Draw.Create(0.01)
	# Get USER Options
	
	pup_block= [\
	('Verts: free', CLEAN_VERTS_FREE, 'Remove verts that are not used by an edge or a face.'),\
	('Edges: free', CLEAN_EDGE_NOFACE, 'Remove edges that are not in a face.'),\
	('Edges: short', CLEAN_EDGE_SMALL, 'Remove edges that are below the length limit.'),\
	('Faces: small perimeter', CLEAN_FACE_PERIMETER, 'Remove faces below the perimeter limit.'),\
	('Faces: small area', CLEAN_FACE_SMALL, 'Remove faces below the area limit (may remove faces stopping T-face artifacts).'),\
	'Materials',\
	('Material Clean', CLEAN_MATERIALS, 'Remove unused materials.'),\
	'VGroups',\
	('Group Clean', CLEAN_GROUP, 'Remove vertex groups that have no verts using them.'),\
	('Weight Clean', CLEAN_VWEIGHT, 'Remove zero weighted verts from groups (limit is zero threshold).'),\
	('Weight Normalize', CLEAN_WEIGHT_NORMALIZE, 'Make the sum total of vertex weights accross vgroups 1.0 for each vertex.'),\
	'',\
	('limit: ', limit, 0.001, 1.0, 'Limit used for the area and length tests above (a higher limit will remove more data).'),\
	'',\
	('All Mesh Data', CLEAN_ALL_DATA, 'Warning! Operate on ALL mesh objects in your Blend file. Use with care'),\
	]
	
	if not Draw.PupBlock('Clean Selected Meshes...', pup_block):
		return
	
	CLEAN_VERTS_FREE= CLEAN_VERTS_FREE.val
	CLEAN_EDGE_NOFACE= CLEAN_EDGE_NOFACE.val
	CLEAN_EDGE_SMALL= CLEAN_EDGE_SMALL.val
	CLEAN_FACE_PERIMETER= CLEAN_FACE_PERIMETER.val
	CLEAN_FACE_SMALL= CLEAN_FACE_SMALL.val
	CLEAN_MATERIALS= CLEAN_MATERIALS.val
	CLEAN_GROUP= CLEAN_GROUP.val
	CLEAN_VWEIGHT= CLEAN_VWEIGHT.val
	CLEAN_WEIGHT_NORMALIZE= CLEAN_WEIGHT_NORMALIZE.val
	limit= limit.val
	CLEAN_ALL_DATA= CLEAN_ALL_DATA.val
	
	if is_editmode: Window.EditMode(0)
	
	if CLEAN_ALL_DATA:
		if CLEAN_GROUP or CLEAN_VWEIGHT or CLEAN_WEIGHT_NORMALIZE:
			# For groups we need the objects linked to the mesh
			meshes= [ob.getData(mesh=1) for ob in Object.Get() if ob.getType() == 'Mesh']
		else:
			meshes= Mesh.Get()
	else:
		meshes= [ob.getData(mesh=1) for ob in obsel if ob.getType() == 'Mesh']
	
	rem_face_count= rem_edge_count= rem_vert_count= rem_material_count= rem_group_count= rem_vweight_count= 0
	
	for me in meshes:
		if CLEAN_FACE_SMALL:
			rem_face_count += rem_area_faces(me, limit)
			
		if CLEAN_FACE_PERIMETER:
			rem_face_count += rem_perimeter_faces(me, limit)
		
		if CLEAN_EDGE_SMALL: # for all use 2- remove all edges.
			rem_edge_count += rem_free_edges(me, limit)
		
		if CLEAN_EDGE_NOFACE:
			rem_edge_count += rem_free_edges(me)
		
		if CLEAN_VERTS_FREE:
			rem_vert_count += rem_free_verts(me)
		
		if CLEAN_MATERIALS:
			rem_material_count += rem_unused_materials(me)
		
		if CLEAN_VWEIGHT or CLEAN_GROUP or CLEAN_WEIGHT_NORMALIZE:
			groupNames, vWeightDict= meshWeight2Dict(me)
			
			if CLEAN_VWEIGHT:
				rem_vweight_count += rem_zero_weights(me, limit, groupNames, vWeightDict)
			
			if CLEAN_GROUP:
				rem_group_count += rem_free_groups(me, groupNames, vWeightDict)
				pass
			
			if CLEAN_WEIGHT_NORMALIZE:
				normalize_vweight(me, groupNames, vWeightDict)
			
			# Copy back to mesh vertex groups.
			dict2MeshWeight(me, groupNames, vWeightDict)
			
		
	if is_editmode: Window.EditMode(0)
	stat_string= 'Removed from ' + str(len(meshes)) + ' Mesh(es)%t|'
	
	if CLEAN_VERTS_FREE:							stat_string+= 'Verts: %i|' % rem_edge_count
	if CLEAN_EDGE_SMALL or CLEAN_EDGE_NOFACE:		stat_string+= 'Edges: %i|' % rem_edge_count
	if CLEAN_FACE_SMALL or CLEAN_FACE_PERIMETER:	stat_string+= 'Faces: %i|' % rem_face_count
	if CLEAN_MATERIALS:								stat_string+= 'Materials: %i|' % rem_material_count
	if CLEAN_VWEIGHT:								stat_string+= 'VWeights: %i|' % rem_vweight_count
	if CLEAN_GROUP:									stat_string+= 'VGroups: %i|' % rem_group_count
	
	Draw.PupMenu(stat_string)
	
	
if __name__ == '__main__':
	main()