io_import_scene_mhx.py

# ##### 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 #####

# Project Name:        MakeHuman
# Product Home Page:   http://www.makehuman.org/
# Code Home Page:      http://code.google.com/p/makehuman/
# Authors:             Thomas Larsson
# Script copyright (C) MakeHuman Team 2001-2011
# Coding Standards:    See http://sites.google.com/site/makehumandocs/developers-guide

"""
Abstract
MHX (MakeHuman eXchange format) importer for Blender 2.5x.
Version 1.4.0

This script should be distributed with Blender.
If not, place it in the .blender/scripts/addons dir
Activate the script in the "Add-Ons" tab (user preferences).
Access from the File > Import menu.

Alternatively, run the script in the script editor (Alt-P), and access from the File > Import menu
"""

bl_info = {
    'name': 'Import: MakeHuman (.mhx)',
    'author': 'Thomas Larsson',
    'version': (1, 4, 0),
    "blender": (2, 5, 7),
    "api": 35774,
    'location': "File > Import > MakeHuman (.mhx)",
    'description': 'Import files in the MakeHuman eXchange format (.mhx)',
    'warning': '',
    'wiki_url': 'http://sites.google.com/site/makehumandocs/blender-export-and-mhx',
    'tracker_url': 'https://projects.blender.org/tracker/index.php?'\
        'func=detail&aid=21872',
    'category': 'Import-Export'}

MAJOR_VERSION = 1
MINOR_VERSION = 4
SUB_VERSION = 0
BLENDER_VERSION = (2, 57, 0)

#
#
#

import bpy
import os
import time
import mathutils
from mathutils import Matrix
#import geometry
#import string

MHX249 = False
Blender24 = False
Blender25 = True
TexDir = "~/makehuman/exports"

#
#
#

theScale = 1.0
One = 1.0/theScale
useMesh = 1
verbosity = 2
warnedTextureDir = False
warnedVersion = False

true = True
false = False
Epsilon = 1e-6
nErrors = 0
theTempDatum = None

todo = []

#
#    toggle flags
#

T_EnforceVersion = 0x01
T_Clothes = 0x02
T_Stretch = 0x04
T_Bend = 0x08

T_Diamond = 0x10
T_Replace = 0x20
T_Face = 0x40
T_Shape = 0x80

T_Mesh = 0x100
T_Armature = 0x200
T_Proxy = 0x400
T_Cage = 0x800

T_Rigify = 0x1000
T_Opcns = 0x2000
T_Symm = 0x4000

toggle = T_EnforceVersion + T_Replace + T_Mesh + T_Armature + T_Face + T_Shape + T_Proxy + T_Clothes

#
#    Blender versions
#

BLENDER_GRAPHICALL = 0
BLENDER_256a = 1

BlenderVersions = ['Graphicall', 'Blender256a']
theBlenderVersion = BLENDER_GRAPHICALL

#
#    setFlagsAndFloats(rigFlags):
#
#    Global floats
#fFingerPanel = 0.0
#fFingerIK = 0.0
fNoStretch = 0.0

#    rigLeg and rigArm flags
T_Toes = 0x0001
#T_GoboFoot = 0x0002

#T_InvFoot = 0x0010
#T_InvFootPT = 0x0020
#T_InvFootNoPT = 0x0040

#T_FingerPanel = 0x100
#T_FingerRot = 0x0200
#T_FingerIK = 0x0400


#T_LocalFKIK = 0x8000

#rigLeg = 0
#rigArm = 0

def setFlagsAndFloats():
    '''
    global toggle, rigLeg, rigArm

    (footRig, fingerRig) = rigFlags
    rigLeg = 0
    if footRig == 'Reverse foot': 
        rigLeg |= T_InvFoot
        if toggle & T_PoleTar:
            rigLeg |= T_InvFootPT
        else:
            rigLeg |= T_InvFootNoPT
    elif footRig == 'Gobo': rigLeg |= T_GoboFoot        

    rigArm = 0
    if fingerRig == 'Panel': rigArm |= T_FingerPanel
    elif fingerRig == 'Rotation': rigArm |= T_FingerRot
    elif fingerRig == 'IK': rigArm |= T_FingerIK

    toggle |= T_Panel
    '''
    global fNoStretch
    if toggle&T_Stretch: fNoStretch == 0.0
    else: fNoStretch = 1.0

    return


#
#    Dictionaries
#

loadedData = {
    'NONE' : {},

    'Object' : {},
    'Mesh' : {},
    'Armature' : {},
    'Lamp' : {},
    'Camera' : {},
    'Lattice' : {},
    'Curve' : {},
    'Text' : {},

    'Material' : {},
    'Image' : {},
    'MaterialTextureSlot' : {},
    'Texture' : {},
    
    'Bone' : {},
    'BoneGroup' : {},
    'Rigify' : {},

    'Action' : {},
    'Group' : {},

    'MeshTextureFaceLayer' : {},
    'MeshColorLayer' : {},
    'VertexGroup' : {},
    'ShapeKey' : {},
    'ParticleSystem' : {},

    'ObjectConstraints' : {},
    'ObjectModifiers' : {},
    'MaterialSlot' : {},
}

Plural = {
    'Object' : 'objects',
    'Mesh' : 'meshes',
    'Lattice' : 'lattices',
    'Curve' : 'curves',
    'Text' : 'texts',
    'Group' : 'groups',
    'Empty' : 'empties',
    'Armature' : 'armatures',
    'Bone' : 'bones',
    'BoneGroup' : 'bone_groups',
    'Pose' : 'poses',
    'PoseBone' : 'pose_bones',
    'Material' : 'materials',
    'Texture' : 'textures',
    'Image' : 'images',
    'Camera' : 'cameras',
    'Lamp' : 'lamps',
    'World' : 'worlds',
}

#
#    checkBlenderVersion()
#

def checkBlenderVersion():
    print("Found Blender", bpy.app.version)
    (A, B, C) = bpy.app.version
    (a, b, c) = BLENDER_VERSION
    if a <= A: return
    if b <= B: return
    if c <= C: return
    msg = (
"This version of the MHX importer only works with Blender (%d, %d, %d) or later. " % (a, b, c) +
"Download a more recent Blender from www.blender.org or www.graphicall.org.\n"
    )
    raise NameError(msg)
    return

#
#    readMhxFile(filePath):
#

def readMhxFile(filePath):
    global todo, nErrors, theScale, defaultScale, One, toggle

    #checkBlenderVersion()    
    
    defaultScale = theScale
    One = 1.0/theScale

    fileName = os.path.expanduser(filePath)
    (shortName, ext) = os.path.splitext(fileName)
    if ext.lower() != ".mhx":
        print("Error: Not a mhx file: " + fileName)
        return
    print( "Opening MHX file "+ fileName )
    time1 = time.clock()

    ignore = False
    stack = []
    tokens = []
    key = "toplevel"
    level = 0
    nErrors = 0
    comment = 0
    nesting = 0

    setFlagsAndFloats()

    file= open(fileName, "rU")
    print( "Tokenizing" )
    lineNo = 0
    for line in file: 
        # print(line)
        lineSplit= line.split()
        lineNo += 1
        if len(lineSplit) == 0:
            pass
        elif lineSplit[0][0] == '#':
            if lineSplit[0] == '#if':
                if comment == nesting:
                    try:
                        res = eval(lineSplit[1])
                    except:
                        res = False
                    if res:
                        comment += 1
                nesting += 1
            elif lineSplit[0] == '#else':
                if comment == nesting-1:
                    comment += 1
                elif comment == nesting:
                    comment -= 1
            elif lineSplit[0] == '#endif':
                if comment == nesting:
                    comment -= 1
                nesting -= 1
        elif comment < nesting:
            pass
        elif lineSplit[0] == 'end':
            try:
                sub = tokens
                tokens = stack.pop()
                if tokens:
                    tokens[-1][2] = sub
                level -= 1
            except:
                print( "Tokenizer error at or before line %d" % lineNo )
                print( line )
                dummy = stack.pop()
        elif lineSplit[-1] == ';':
            if lineSplit[0] == '\\':
                key = lineSplit[1]
                tokens.append([key,lineSplit[2:-1],[]])
            else:
                key = lineSplit[0]
                tokens.append([key,lineSplit[1:-1],[]])
        else:
            key = lineSplit[0]
            tokens.append([key,lineSplit[1:],[]])
            stack.append(tokens)
            level += 1
            tokens = []
    file.close()

    if level != 0:
        raise NameError("Tokenizer out of kilter %d" % level)    
    clearScene()
    print( "Parsing" )
    parse(tokens)
    
    for (expr, glbals, lcals) in todo:
        try:
            print("Doing %s" % expr)
            exec(expr, glbals, lcals)
        except:
            msg = "Failed: "+expr
            print( msg )
            nErrors += 1
            #raise NameError(msg)

    time2 = time.clock()
    print("toggle = %x" % toggle)
    msg = "File %s loaded in %g s" % (fileName, time2-time1)
    if nErrors:
        msg += " but there where %d errors. " % (nErrors)
    print(msg)
    return

#
#    getObject(name, var, glbals, lcals):
#

def getObject(name, var, glbals, lcals):
    try:
        ob = loadedData['Object'][name]
    except:
        if name != "None":
            pushOnTodoList(None, "ob = loadedData['Object'][name]" % globals(), locals())
        ob = None
    return ob

#
#    checkMhxVersion(major, minor):
#

def checkMhxVersion(major, minor):
    global warnedVersion
    print((major,minor), (MAJOR_VERSION, MINOR_VERSION), warnedVersion)
    if  major != MAJOR_VERSION or minor != MINOR_VERSION:
        if warnedVersion:
            return
        else:
            msg = (
"Wrong MHX version\n" +
"Expected MHX %d.%d but the loaded file has version MHX %d.%d\n" % (MAJOR_VERSION, MINOR_VERSION, major, minor) +
"You can disable this error message by deselecting the Enforce version option when importing. " +
"Alternatively, you can try to download the most recent nightly build from www.makehuman.org. " +
"The current version of the import script is located in the importers/mhx/blender25x folder and is called import_scene_mhx.py. " +
"The version distributed with Blender builds from www.graphicall.org may be out of date.\n"
)
        if toggle & T_EnforceVersion:
            raise NameError(msg)
        else:
            print(msg)
            warnedVersion = True
    return

#
#    parse(tokens):
#

ifResult = False

def parse(tokens):
    global MHX249, ifResult, theScale, defaultScale, One
    
    for (key, val, sub) in tokens:    
        print("Parse %s" % key)
        data = None
        if key == 'MHX':
            checkMhxVersion(int(val[0]), int(val[1]))
        elif key == 'MHX249':
            MHX249 = eval(val[0])
            print("Blender 2.49 compatibility mode is %s\n" % MHX249)
        elif MHX249:
            pass
        elif key == 'print':
            msg = concatList(val)
            print(msg)
        elif key == 'warn':
            msg = concatList(val)
            print(msg)
        elif key == 'error':
            msg = concatList(val)
            raise NameError(msg)    
        elif key == 'NoScale':
            if eval(val[0]):
                theScale = 1.0
            else:
                theScale = defaultScale        
            One = 1.0/theScale
        elif key == "Object":
            parseObject(val, sub)
        elif key == "Mesh":
            data = parseMesh(val, sub)
        elif key == "Armature":
            data = parseArmature(val, sub)
        elif key == "Pose":
            data = parsePose(val, sub)
        elif key == "Action":
            data = parseAction(val, sub)
        elif key == "Material":
            data = parseMaterial(val, sub)
        elif key == "Texture":
            data = parseTexture(val, sub)
        elif key == "Image":
            data = parseImage(val, sub)
        elif key == "Curve":
            data = parseCurve(val, sub)
        elif key == "TextCurve":
            data = parseTextCurve(val, sub)
        elif key == "Lattice":
            data = parseLattice(val, sub)
        elif key == "Group":
            data = parseGroup(val, sub)
        elif key == "Lamp":
            data = parseLamp(val, sub)
        elif key == "World":
            data = parseWorld(val, sub)
        elif key == "Scene":
            data = parseScene(val, sub)
        elif key == "DefineProperty":
            parseDefineProperty(val, sub)
        elif key == "Process":
            parseProcess(val, sub)
        elif key == "PostProcess":
            postProcess(val)
            hideLayers(val)
        elif key == "CorrectRig":
            correctRig(val)
        elif key == 'AnimationData':
            try:
                ob = loadedData['Object'][val[0]]
            except:
                ob = None
            if ob:
                bpy.context.scene.objects.active = ob
                parseAnimationData(ob, val, sub)
        elif key == 'MaterialAnimationData':
            try:
                ob = loadedData['Object'][val[0]]
            except:
                ob = None
            if ob:
                bpy.context.scene.objects.active = ob
                mat = ob.data.materials[int(val[2])]
                print("matanim", ob, mat)
                parseAnimationData(mat, val, sub)
        elif key == 'ShapeKeys':
            try:
                ob = loadedData['Object'][val[0]]
            except:
                raise NameError("ShapeKeys object %s does not exist" % val[0])
            if ob:
                bpy.context.scene.objects.active = ob
                parseShapeKeys(ob, ob.data, val, sub)        
        else:
            data = parseDefaultType(key, val, sub)                

        if data and key != 'Mesh':
            print( data )
    return

#
#    parseDefaultType(typ, args, tokens):
#

def parseDefaultType(typ, args, tokens):
    global todo

    name = args[0]
    data = None
    expr = "bpy.data.%s.new('%s')" % (Plural[typ], name)
    # print(expr)
    data = eval(expr)
    # print("  ok", data)

    bpyType = typ.capitalize()
    print(bpyType, name, data)
    loadedData[bpyType][name] = data
    if data is None:
        return None

    for (key, val, sub) in tokens:
        #print("%s %s" % (key, val))
        defaultKey(key, val, sub, 'data', [], globals(), locals())
    print("Done ", data)
    return data
    
#
#    concatList(elts)
#

def concatList(elts):
    string = ""
    for elt in elts:
        string += " %s" % elt
    return string

#
#    parseAction(args, tokens):
#    parseFCurve(fcu, args, tokens):
#    parseKeyFramePoint(pt, args, tokens):
#

def parseAction(args, tokens):
    name = args[0]
    if invalid(args[1]):
        return

    ob = bpy.context.object
    bpy.ops.object.mode_set(mode='POSE')
    if ob.animation_data:
        ob.animation_data.action = None
    created = {}
    for (key, val, sub) in tokens:
        if key == 'FCurve':
            prepareActionFCurve(ob, created, val, sub)
        
    act = ob.animation_data.action
    loadedData['Action'][name] = act
    if act is None:
        print("Ignoring action %s" % name)
        return act
    act.name = name
    print("Action", name, act, ob)
    
    for (key, val, sub) in tokens:
        if key == 'FCurve':
            fcu = parseActionFCurve(act, ob, val, sub)
        else:
            defaultKey(key, val, sub, 'act', [], globals(), locals())
    ob.animation_data.action = None
    bpy.ops.object.mode_set(mode='OBJECT')
    return act

def prepareActionFCurve(ob, created, args, tokens):            
    dataPath = args[0]
    index = args[1]
    (expr, channel) = channelFromDataPath(dataPath, index)
    try:
        if channel in created[expr]:
            return
        else:
            created[expr].append(channel)
    except:
        created[expr] = [channel]

    times = []
    for (key, val, sub) in tokens:
        if key == 'kp':
            times.append(int(val[0]))

    try:
        data = eval(expr)
    except:
        print("Ignoring illegal expression: %s" % expr)
        return

    n = 0
    for t in times:
        #bpy.context.scene.current_frame = t
        bpy.ops.anim.change_frame(frame = t)
        try:
            data.keyframe_insert(channel)
            n += 1
        except:
            pass
            #print("failed", data, expr, channel)
    if n != len(times):
        print("Mismatch", n, len(times), expr, channel)
    return

def channelFromDataPath(dataPath, index):
    words = dataPath.split(']')
    if len(words) == 1:
        # location
        expr = "ob"
        channel = dataPath
    elif len(words) == 2:
        # pose.bones["tongue"].location
        expr = "ob.%s]" % (words[0])
        cwords = words[1].split('.')
        channel = cwords[1]
    elif len(words) == 3:
        # pose.bones["brow.R"]["mad"]
        expr = "ob.%s]" % (words[0])
        cwords = words[1].split('"')
        channel = cwords[1]
    # print(expr, channel, index)
    return (expr, channel)

def parseActionFCurve(act, ob, args, tokens):
    dataPath = args[0]
    index = args[1]
    (expr, channel) = channelFromDataPath(dataPath, index)
    index = int(args[1])

    success = False
    for fcu in act.fcurves:
        (expr1, channel1) = channelFromDataPath(fcu.data_path, fcu.array_index)
        if expr1 == expr and channel1 == channel and fcu.array_index == index:
            success = True
            break
    if not success:
        return None

    n = 0
    for (key, val, sub) in tokens:
        if key == 'kp':
            try:
                pt = fcu.keyframe_points[n]
                pt.interpolation = 'LINEAR'
                pt = parseKeyFramePoint(pt, val, sub)
                n += 1
            except:
                pass
                #print(tokens)
                #raise NameError("kp", fcu, n, len(fcu.keyframe_points), val)
        else:
            defaultKey(key, val, sub, 'fcu', [], globals(), locals())
    return fcu

def parseKeyFramePoint(pt, args, tokens):
    pt.co = (float(args[0]), float(args[1]))
    if len(args) > 2:
        pt.handle1 = (float(args[2]), float(args[3]))
        pt.handle2 = (float(args[3]), float(args[5]))
    return pt

#
#    parseAnimationData(rna, args, tokens):
#    parseDriver(drv, args, tokens):
#    parseDriverVariable(var, args, tokens):
#

def parseAnimationData(rna, args, tokens):
    if not eval(args[1]):
        return
    print("Parse Animation data")
    if rna.animation_data is None:    
        rna.animation_data_create()
    adata = rna.animation_data
    for (key, val, sub) in tokens:
        if key == 'FCurve':
            fcu = parseAnimDataFCurve(adata, rna, val, sub)            
        else:
            defaultKey(key, val, sub, 'adata', [], globals(), locals())
    print(adata)
    return adata

def parseAnimDataFCurve(adata, rna, args, tokens):
    global theBlenderVersion
    if invalid(args[2]):
        return
    dataPath = args[0]
    index = int(args[1])
    n = 1
    for (key, val, sub) in tokens:
        if key == 'Driver':
            fcu = parseDriver(adata, dataPath, index, rna, val, sub)
            fmod = fcu.modifiers[0]
            fcu.modifiers.remove(fmod)
        elif key == 'FModifier':
            parseFModifier(fcu, val, sub)
        elif key == 'kp':
            if theBlenderVersion >= BLENDER_256a:
                pt = fcu.keyframe_points.add(n, 0)
            else:
                pt = fcu.keyframe_points.insert(n, 0)
            pt.interpolation = 'LINEAR'
            pt = parseKeyFramePoint(pt, val, sub)
            n += 1
        else:
            defaultKey(key, val, sub, 'fcu', [], globals(), locals())
    return fcu

"""
        fcurve = con.driver_add("influence", 0)
        driver = fcurve.driver
        driver.type = 'AVERAGE'
"""
def parseDriver(adata, dataPath, index, rna, args, tokens):
    if dataPath[-1] == ']':
        words = dataPath.split(']')
        expr = "rna." + words[0] + ']'
        pwords = words[1].split('"')
        prop = pwords[1]
        #print("prop", expr, prop)
        bone = eval(expr)
        return None
    else:
        words = dataPath.split('.')
        channel = words[-1]
        expr = "rna"
        for n in range(len(words)-1):
            expr += "." + words[n]
        expr += ".driver_add('%s', index)" % channel
    
    #print("expr", rna, expr)
    fcu = eval(expr)
    drv = fcu.driver
    #print("   Driver type", drv, args[0])
    drv.type = args[0]
    #print("   ->", drv.type)
    for (key, val, sub) in tokens:
        if key == 'DriverVariable':
            var = parseDriverVariable(drv, rna, val, sub)
        else:
            defaultKey(key, val, sub, 'drv', [], globals(), locals())
    return fcu

def parseDriverVariable(drv, rna, args, tokens):
    var = drv.variables.new()
    var.name = args[0]
    #print("   Var type", var, args[1])
    var.type = args[1]
    #print("   ->", var.type)
    nTarget = 0
    for (key, val, sub) in tokens:
        if key == 'Target':
            parseDriverTarget(var, nTarget, rna, val, sub)
            nTarget += 1
        else:
            defaultKey(key, val, sub, 'var', [], globals(), locals())
    return var

def parseFModifier(fcu, args, tokens):
    fmod = fcu.modifiers.new(args[0])
    #fmod = fcu.modifiers[0]
    for (key, val, sub) in tokens:
        defaultKey(key, val, sub, 'fmod', [], globals(), locals())
    return fmod

"""
        var = driver.variables.new()
        var.name = target_bone
        var.targets[0].id_type = 'OBJECT'
        var.targets[0].id = obj
        var.targets[0].rna_path = driver_path
"""
def parseDriverTarget(var, nTarget, rna, args, tokens):
    targ = var.targets[nTarget]
    ob = loadedData['Object'][args[0]]
    #print("    targ id", targ, ob)
    targ.id = ob
    #print("    ->", targ.id)
    for (key, val, sub) in tokens:
        defaultKey(key, val, sub, 'targ', [], globals(), locals())
    return targ

    
#
#    parseMaterial(args, ext, tokens):
#    parseMTex(mat, args, tokens):
#    parseTexture(args, tokens):
#

def parseMaterial(args, tokens):
    global todo
    name = args[0]
    mat = bpy.data.materials.new(name)
    if mat is None:
        return None
    loadedData['Material'][name] = mat
    for (key, val, sub) in tokens:
        if key == 'MTex':
            parseMTex(mat, val, sub)
        elif key == 'Ramp':
            parseRamp(mat, val, sub)
        elif key == 'RaytraceTransparency':
            parseDefault(mat.raytrace_transparency, sub, {}, [])
        elif key == 'Halo':
            parseDefault(mat.halo, sub, {}, [])
        elif key == 'SSS':
            parseDefault(mat.subsurface_scattering, sub, {}, [])
        elif key == 'Strand':
            parseDefault(mat.strand, sub, {}, [])
        elif key == 'NodeTree':
            mat.use_nodes = True
            parseNodeTree(mat.node_tree, val, sub)
        else:
            exclude = ['specular_intensity', 'tangent_shading']
            defaultKey(key, val, sub, 'mat', [], globals(), locals())
    
    return mat

def parseMTex(mat, args, tokens):
    global todo
    index = int(args[0])
    texname = args[1]
    texco = args[2]
    mapto = args[3]
    tex = loadedData['Texture'][texname]
    mtex = mat.texture_slots.add()
    mtex.texture_coords = texco
    mtex.texture = tex

    for (key, val, sub) in tokens:
        defaultKey(key, val, sub, "mtex", [], globals(), locals())

    return mtex

def parseTexture(args, tokens):
    global todo
    if verbosity > 2:
        print( "Parsing texture %s" % args )
    name = args[0]
    tex = bpy.data.textures.new(name=name, type=args[1])
    loadedData['Texture'][name] = tex
    
    for (key, val, sub) in tokens:
        if key == 'Image':
            try:
                imgName = val[0]
                img = loadedData['Image'][imgName]
                tex.image = img
            except:
                msg = "Unable to load image '%s'" % val[0]
        elif key == 'Ramp':
            parseRamp(tex, val, sub)
        elif key == 'NodeTree':
            tex.use_nodes = True
            parseNodeTree(tex.node_tree, val, sub)
        else:
            defaultKey(key, val,  sub, "tex", ['use_nodes', 'use_textures', 'contrast'], globals(), locals())

    return tex

def parseRamp(data, args, tokens):
    nvar = "data.%s" % args[0]
    use = "data.use_%s = True" % args[0]
    exec(use)
    ramp = eval(nvar)
    elts = ramp.elements
    n = 0
    for (key, val, sub) in tokens:
        # print("Ramp", key, val)
        if key == 'Element':
            elts[n].color = eval(val[0])
            elts[n].position = eval(val[1])
            n += 1
        else:
            defaultKey(key, val,  sub, "tex", ['use_nodes', 'use_textures', 'contrast'], globals(), locals())
    
def parseSSS(mat, args, tokens):
    sss = mat.subsurface_scattering
    for (key, val, sub) in tokens:
        defaultKey(key, val, sub, "sss", [], globals(), locals())

def parseStrand(mat, args, tokens):
    strand = mat.strand
    for (key, val, sub) in tokens:
        defaultKey(key, val, sub, "strand", [], globals(), locals())

#
#    parseNodeTree(tree, args, tokens):
#    parseNode(node, args, tokens):
#    parseSocket(socket, args, tokens):
#

def parseNodeTree(tree, args, tokens):
    return
    print("Tree", tree, args)
    print(list(tree.nodes))
    tree.name = args[0]
    for (key, val, sub) in tokens:
        if key == 'Node':
            parseNodes(tree.nodes, val, sub)
        else:
            defaultKey(key, val, sub, "tree", [], globals(), locals())

def parseNodes(nodes, args, tokens):
    print("Nodes", nodes, args)
    print(list(nodes))
    node.name = args[0]
    for (key, val, sub) in tokens:
        if key == 'Inputs':
            parseSocket(node.inputs, val, sub)
        elif key == 'Outputs':
            parseSocket(node.outputs, val, sub)
        else:
            defaultKey(key, val, sub, "node", [], globals(), locals())

def parseNode(node, args, tokens):
    print("Node", node, args)
    print(list(node.inputs), list(node.outputs))
    node.name = args[0]
    for (key, val, sub) in tokens:
        if key == 'Inputs':
            parseSocket(node.inputs, val, sub)
        elif key == 'Outputs':
            parseSocket(node.outputs, val, sub)
        else:
            defaultKey(key, val, sub, "node", [], globals(), locals())

def parseSocket(socket, args, tokens):
    print("Socket", socket, args)
    socket.name = args[0]
    for (key, val, sub) in tokens:
        if key == 'Node':
            parseNode(tree.nodes, val, sub)
        else:
            defaultKey(key, val, sub, "tree", [], globals(), locals())



#
#    doLoadImage(filepath):
#    loadImage(filepath):
#    parseImage(args, tokens):
#

def doLoadImage(filepath):        
    path1 = os.path.expanduser(filepath)
    file1 = os.path.realpath(path1)
    if os.path.isfile(file1):
        print( "Found file "+file1 )
        try:
            img = bpy.data.images.load(file1)
            return img
        except:
            print( "Cannot read image" )
            return None
    else:
        print( "No file "+file1 )
        return None


def loadImage(filepath):
    global TexDir, warnedTextureDir, loadedData

    texDir = os.path.expanduser(TexDir)
    path1 = os.path.expanduser(filepath)
    file1 = os.path.realpath(path1)
    (path, filename) = os.path.split(file1)
    (name, ext) = os.path.splitext(filename)
    print( "Loading ", filepath, " = ", filename )

    # img = doLoadImage(texDir+"/"+name+".png")
    # if img:
    #    return img

    img = doLoadImage(texDir+"/"+filename)
    if img:
        return img