#!BPY
"""
Name: 'Normalize/Scale Weight...'
Blender: 241
Group: 'WeightPaint'
Tooltip: 'Normalize the weight of the active weightgroup.'
"""

__author__ = ["Campbell Barton"]
__url__ = ("blender", "elysiun", "http://members.iinet.net.au/~cpbarton/ideasman/")
__version__ = "0.1"
__bpydoc__ = """\

Normalize Weights

This Script is to be used only in weight paint mode,
It Normalizes the weights of the current group, to the desired peak
optionaly scaling groups that are shared by these verts so the
proportion of the veighting is unchanged.
"""

# ***** BEGIN GPL LICENSE BLOCK *****
#
# Script copyright (C) Campbell J Barton
#
# 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
# ***** END GPL LICENCE BLOCK *****
# --------------------------------------------------------------------------

from Blender import Scene, Draw
import BPyMesh
SMALL_NUM= 0.000001
def actWeightNormalize(me, PREF_PEAKWEIGHT, PREF_KEEP_PROPORTION):
	
	groupNames, vWeightDict= BPyMesh.meshWeight2Dict(me)
	new_weight= max_weight= -1.0
	act_group= me.activeGroup
	
	vWeightDictUsed=[False] * len(vWeightDict)
	
	for i, wd in enumerate(vWeightDict):
		try:
			new_weight= wd[act_group]
			if new_weight > max_weight:
				max_weight= new_weight
			vWeightDictUsed[i]=wd
		except:
			pass
	
	if max_weight < SMALL_NUM or new_weight == -1:
		Draw.PupMenu('No verts to normalize. exiting.')
		return
	
	if abs(max_weight-PREF_PEAKWEIGHT) < SMALL_NUM:
		Draw.PupMenu('Vert Weights are alredy normalized.')
		return
	
	max_weight= max_weight/PREF_PEAKWEIGHT
	
	if PREF_KEEP_PROPORTION:
		# TODO, PROPORTIONAL WEIGHT SCALING.
		for wd in vWeightDictUsed:
			if wd: # not false.
				if len(wd) == 1:
					# Only 1 group for thsi vert. Simple
					wd[act_group] /= max_weight
				else:
					# More then 1 group. will need to scale all users evenly.
					local_maxweight= max(wd.itervalues()) / PREF_PEAKWEIGHT
					for weight in wd.iterkeys():
						wd[weight] /= local_maxweight
				
				
	else: # Simple, just scale the weights up.
		for wd in vWeightDictUsed:
			if wd: # not false.
				wd[act_group] /= max_weight
		
	# Copy weights back to the mesh.
	BPyMesh.dict2MeshWeight(me, groupNames, vWeightDict)
	

def main():
	scn= Scene.GetCurrent()
	ob= scn.objects.active
	
	if not ob or ob.type != 'Mesh':
		Draw.PupMenu('Error, no active mesh object, aborting.')
		return
	
	me= ob.getData(mesh=1)
	
	PREF_PEAKWEIGHT= Draw.Create(1.0)
	PREF_KEEP_PROPORTION= Draw.Create(1)
	
	pup_block= [\
	('Peak Weight:', PREF_PEAKWEIGHT, 0.01, 1.0, 'Upper weight for normalizing.'),\
	('Proportional', PREF_KEEP_PROPORTION, 'Scale other weights so verts (Keep weights with other groups in proportion).'),\
	]
	
	if not Draw.PupBlock('Clean Selected Meshes...', pup_block):
		return
	
	actWeightNormalize(me, PREF_PEAKWEIGHT.val, PREF_KEEP_PROPORTION.val)
	
if __name__=='__main__':
	main()