uvcalc_smart_project.py

# --------------------------------------------------------------------------
# Smart Projection UV Projection Unwrapper v1.2 by Campbell Barton (AKA Ideasman)
# --------------------------------------------------------------------------
# ***** 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 LICENCE BLOCK *****
# --------------------------------------------------------------------------

# <pep8 compliant>

from mathutils import Matrix, Vector, geometry
import time
import bpy
from math import cos, radians

DEG_TO_RAD = 0.017453292519943295 # pi/180.0
SMALL_NUM = 0.000000001
BIG_NUM = 1e15

global USER_FILL_HOLES
global USER_FILL_HOLES_QUALITY
USER_FILL_HOLES = None
USER_FILL_HOLES_QUALITY = None

dict_matrix = {}

def pointInTri2D(v, v1, v2, v3):
    global dict_matrix

    key = v1.x, v1.y, v2.x, v2.y, v3.x, v3.y

    # Commented because its slower to do teh bounds check, we should realy cache the bounds info for each face.
    '''
    # BOUNDS CHECK
    xmin= 1000000
    ymin= 1000000

    xmax= -1000000
    ymax= -1000000

    for i in (0,2,4):
        x= key[i]
        y= key[i+1]

        if xmax<x:	xmax= x
        if ymax<y:	ymax= y
        if xmin>x:	xmin= x
        if ymin>y:	ymin= y

    x= v.x
    y= v.y

    if x<xmin or x>xmax or y < ymin or y > ymax:
        return False
    # Done with bounds check
    '''
    try:
        mtx = dict_matrix[key]
        if not mtx:
            return False
    except:
        side1 = v2 - v1
        side2 = v3 - v1

        nor = side1.cross(side2)

        l1 = [side1[0], side1[1], side1[2]]
        l2 = [side2[0], side2[1], side2[2]]
        l3 = [nor[0], nor[1], nor[2]]

        mtx = Matrix(l1, l2, l3)

        # Zero area 2d tri, even tho we throw away zerop area faces
        # the projection UV can result in a zero area UV.
        if not mtx.determinant():
            dict_matrix[key] = None
            return False

        mtx.invert()

        dict_matrix[key] = mtx

    uvw = (v - v1) * mtx
    return 0 <= uvw[0] and 0 <= uvw[1] and uvw[0] + uvw[1] <= 1


def boundsIsland(faces):
    minx = maxx = faces[0].uv[0][0] # Set initial bounds.
    miny = maxy = faces[0].uv[0][1]
    # print len(faces), minx, maxx, miny , maxy
    for f in faces:
        for uv in f.uv:
            x= uv.x
            y= uv.y
            if x<minx: minx= x
            if y<miny: miny= y
            if x>maxx: maxx= x
            if y>maxy: maxy= y

    return minx, miny, maxx, maxy

"""
def boundsEdgeLoop(edges):
    minx = maxx = edges[0][0] # Set initial bounds.
    miny = maxy = edges[0][1]
    # print len(faces), minx, maxx, miny , maxy
    for ed in edges:
        for pt in ed:
            print 'ass'
            x= pt[0]
            y= pt[1]
            if x<minx: x= minx
            if y<miny: y= miny
            if x>maxx: x= maxx
            if y>maxy: y= maxy

    return minx, miny, maxx, maxy
"""

# Turns the islands into a list of unpordered edges (Non internal)
# Onlt for UV's
# only returns outline edges for intersection tests. and unique points.

def island2Edge(island):

    # Vert index edges
    edges = {}

    unique_points= {}

    for f in island:
        f_uvkey= map(tuple, f.uv)


        for vIdx, edkey in enumerate(f.edge_keys):
            unique_points[f_uvkey[vIdx]] = f.uv[vIdx]

            if f.v[vIdx].index > f.v[vIdx-1].index:
                i1= vIdx-1;	i2= vIdx
            else:
                i1= vIdx;	i2= vIdx-1

            try:	edges[ f_uvkey[i1], f_uvkey[i2] ] *= 0 # sets eny edge with more then 1 user to 0 are not returned.
            except:	edges[ f_uvkey[i1], f_uvkey[i2] ] = (f.uv[i1] - f.uv[i2]).length,

    # If 2 are the same then they will be together, but full [a,b] order is not correct.

    # Sort by length


    length_sorted_edges = [(Vector(key[0]), Vector(key[1]), value) for key, value in edges.items() if value != 0]

    try:	length_sorted_edges.sort(key = lambda A: -A[2]) # largest first
    except:	length_sorted_edges.sort(lambda A, B: cmp(B[2], A[2]))

    # Its okay to leave the length in there.
    #for e in length_sorted_edges:
    #	e.pop(2)

    # return edges and unique points
    return length_sorted_edges, [v.__copy__().resize3D() for v in unique_points.values()]

# ========================= NOT WORKING????
# Find if a points inside an edge loop, un-orderd.
# pt is and x/y
# edges are a non ordered loop of edges.
# #offsets are the edge x and y offset.
"""
def pointInEdges(pt, edges):
    #
    x1 = pt[0]
    y1 = pt[1]

    # Point to the left of this line.
    x2 = -100000
    y2 = -10000
    intersectCount = 0
    for ed in edges:
        xi, yi = lineIntersection2D(x1,y1, x2,y2, ed[0][0], ed[0][1], ed[1][0], ed[1][1])
        if xi != None: # Is there an intersection.
            intersectCount+=1

    return intersectCount % 2
"""

def pointInIsland(pt, island):
    vec1, vec2, vec3 = Vector(), Vector(), Vector()
    for f in island:
        vec1.x, vec1.y = f.uv[0]
        vec2.x, vec2.y = f.uv[1]
        vec3.x, vec3.y = f.uv[2]

        if pointInTri2D(pt, vec1, vec2, vec3):
            return True

        if len(f.v) == 4:
            vec1.x, vec1.y = f.uv[0]
            vec2.x, vec2.y = f.uv[2]
            vec3.x, vec3.y = f.uv[3]
            if pointInTri2D(pt, vec1, vec2, vec3):
                return True
    return False


# box is (left,bottom, right, top)
def islandIntersectUvIsland(source, target, SourceOffset):
    # Is 1 point in the box, inside the vertLoops
    edgeLoopsSource = source[6] # Pretend this is offset
    edgeLoopsTarget = target[6]

    # Edge intersect test
    for ed in edgeLoopsSource:
        for seg in edgeLoopsTarget:
            i = geometry.LineIntersect2D(\
            seg[0], seg[1], SourceOffset+ed[0], SourceOffset+ed[1])
            if i:
                return 1 # LINE INTERSECTION

    # 1 test for source being totally inside target
    SourceOffset.resize3D()
    for pv in source[7]:
        if pointInIsland(pv+SourceOffset, target[0]):
            return 2 # SOURCE INSIDE TARGET

    # 2 test for a part of the target being totaly inside the source.
    for pv in target[7]:
        if pointInIsland(pv-SourceOffset, source[0]):
            return 3 # PART OF TARGET INSIDE SOURCE.

    return 0 # NO INTERSECTION




# Returns the X/y Bounds of a list of vectors.
def testNewVecLs2DRotIsBetter(vecs, mat=-1, bestAreaSoFar = -1):

    # UV's will never extend this far.
    minx = miny = BIG_NUM
    maxx = maxy = -BIG_NUM

    for i, v in enumerate(vecs):

        # Do this allong the way
        if mat != -1:
            v = vecs[i] = v*mat
            x= v.x
            y= v.y
            if x<minx: minx= x
            if y<miny: miny= y
            if x>maxx: maxx= x
            if y>maxy: maxy= y

        # Spesific to this algo, bail out if we get bigger then the current area
        if bestAreaSoFar != -1 and (maxx-minx) * (maxy-miny) > bestAreaSoFar:
            return (BIG_NUM, None), None
    w = maxx-minx
    h = maxy-miny
    return (w*h, w,h), vecs # Area, vecs

# Takes a list of faces that make up a UV island and rotate
# until they optimally fit inside a square.
ROTMAT_2D_POS_90D = Matrix.Rotation( radians(90.0), 2)
ROTMAT_2D_POS_45D = Matrix.Rotation( radians(45.0), 2)

RotMatStepRotation = []
rot_angle = 22.5 #45.0/2
while rot_angle > 0.1:
    RotMatStepRotation.append([\
     Matrix.Rotation( radians(rot_angle), 2),\
     Matrix.Rotation( radians(-rot_angle), 2)])

    rot_angle = rot_angle/2.0


def optiRotateUvIsland(faces):
    global currentArea

    # Bestfit Rotation
    def best2dRotation(uvVecs, MAT1, MAT2):
        global currentArea

        newAreaPos, newfaceProjectionGroupListPos =\
        testNewVecLs2DRotIsBetter(uvVecs[:], MAT1, currentArea[0])


        # Why do I use newpos here? May as well give the best area to date for an early bailout
        # some slight speed increase in this.
        # If the new rotation is smaller then the existing, we can
        # avoid copying a list and overwrite the old, crappy one.

        if newAreaPos[0] < currentArea[0]:
            newAreaNeg, newfaceProjectionGroupListNeg =\
            testNewVecLs2DRotIsBetter(uvVecs, MAT2, newAreaPos[0])  # Reuse the old bigger list.
        else:
            newAreaNeg, newfaceProjectionGroupListNeg =\
            testNewVecLs2DRotIsBetter(uvVecs[:], MAT2, currentArea[0])  # Cant reuse, make a copy.


        # Now from the 3 options we need to discover which to use
        # we have cerrentArea/newAreaPos/newAreaNeg
        bestArea = min(currentArea[0], newAreaPos[0], newAreaNeg[0])

        if currentArea[0] == bestArea:
            return uvVecs
        elif newAreaPos[0] == bestArea:
            uvVecs = newfaceProjectionGroupListPos
            currentArea = newAreaPos
        elif newAreaNeg[0] == bestArea:
            uvVecs = newfaceProjectionGroupListNeg
            currentArea = newAreaNeg

        return uvVecs


    # Serialized UV coords to Vectors
    uvVecs = [uv for f in faces  for uv in f.uv]

    # Theres a small enough number of these to hard code it
    # rather then a loop.

    # Will not modify anything
    currentArea, dummy =\
    testNewVecLs2DRotIsBetter(uvVecs)


    # Try a 45d rotation
    newAreaPos, newfaceProjectionGroupListPos = testNewVecLs2DRotIsBetter(uvVecs[:], ROTMAT_2D_POS_45D, currentArea[0])

    if newAreaPos[0] < currentArea[0]:
        uvVecs = newfaceProjectionGroupListPos
        currentArea = newAreaPos
    # 45d done

    # Testcase different rotations and find the onfe that best fits in a square
    for ROTMAT in RotMatStepRotation:
        uvVecs = best2dRotation(uvVecs, ROTMAT[0], ROTMAT[1])

    # Only if you want it, make faces verticle!
    if currentArea[1] > currentArea[2]:
        # Rotate 90d
        # Work directly on the list, no need to return a value.
        testNewVecLs2DRotIsBetter(uvVecs, ROTMAT_2D_POS_90D)


    # Now write the vectors back to the face UV's
    i = 0 # count the serialized uv/vectors
    for f in faces:
        #f.uv = [uv for uv in uvVecs[i:len(f)+i] ]
        for j, k in enumerate(range(i, len(f.v)+i)):
            f.uv[j][:] = uvVecs[k]
        i += len(f.v)


# Takes an island list and tries to find concave, hollow areas to pack smaller islands into.
def mergeUvIslands(islandList):
    global USER_FILL_HOLES
    global USER_FILL_HOLES_QUALITY


    # Pack islands to bottom LHS
    # Sync with island

    #islandTotFaceArea = [] # A list of floats, each island area
    #islandArea = [] # a list of tuples ( area, w,h)


    decoratedIslandList = []

    islandIdx = len(islandList)
    while islandIdx:
        islandIdx-=1
        minx, miny, maxx, maxy = boundsIsland(islandList[islandIdx])
        w, h = maxx-minx, maxy-miny

        totFaceArea = 0
        offset= Vector((minx, miny))
        for f in islandList[islandIdx]:
            for uv in f.uv:
                uv -= offset

            totFaceArea += f.area

        islandBoundsArea = w*h
        efficiency = abs(islandBoundsArea - totFaceArea)

        # UV Edge list used for intersections as well as unique points.
        edges, uniqueEdgePoints = island2Edge(islandList[islandIdx])

        decoratedIslandList.append([islandList[islandIdx], totFaceArea, efficiency, islandBoundsArea, w,h, edges, uniqueEdgePoints])


    # Sort by island bounding box area, smallest face area first.
    # no.. chance that to most simple edge loop first.
    decoratedIslandListAreaSort =decoratedIslandList[:]

    decoratedIslandListAreaSort.sort(key = lambda A: A[3])

    # sort by efficiency, Least Efficient first.
    decoratedIslandListEfficSort = decoratedIslandList[:]
    # decoratedIslandListEfficSort.sort(lambda A, B: cmp(B[2], A[2]))

    decoratedIslandListEfficSort.sort(key = lambda A: -A[2])

    # ================================================== THESE CAN BE TWEAKED.
    # This is a quality value for the number of tests.
    # from 1 to 4, generic quality value is from 1 to 100
    USER_STEP_QUALITY =   ((USER_FILL_HOLES_QUALITY - 1) / 25.0) + 1

    # If 100 will test as long as there is enough free space.
    # this is rarely enough, and testing takes a while, so lower quality speeds this up.

    # 1 means they have the same quality
    USER_FREE_SPACE_TO_TEST_QUALITY = 1 + (((100 - USER_FILL_HOLES_QUALITY)/100.0) *5)

    #print 'USER_STEP_QUALITY', USER_STEP_QUALITY
    #print 'USER_FREE_SPACE_TO_TEST_QUALITY', USER_FREE_SPACE_TO_TEST_QUALITY

    removedCount = 0

    areaIslandIdx = 0
    ctrl = Window.Qual.CTRL
    BREAK= False
    while areaIslandIdx < len(decoratedIslandListAreaSort) and not BREAK:
        sourceIsland = decoratedIslandListAreaSort[areaIslandIdx]
        # Alredy packed?
        if not sourceIsland[0]:
            areaIslandIdx+=1
        else:
            efficIslandIdx = 0
            while efficIslandIdx < len(decoratedIslandListEfficSort) and not BREAK:

                if Window.GetKeyQualifiers() & ctrl:
                    BREAK= True
                    break

                # Now we have 2 islands, is the efficience of the islands lowers theres an
                # increasing likely hood that we can fit merge into the bigger UV island.
                # this ensures a tight fit.

                # Just use figures we have about user/unused area to see if they might fit.

                targetIsland = decoratedIslandListEfficSort[efficIslandIdx]


                if sourceIsland[0] == targetIsland[0] or\
                not targetIsland[0] or\
                not sourceIsland[0]:
                    pass
                else:

                    # ([island, totFaceArea, efficiency, islandArea, w,h])
                    # Waisted space on target is greater then UV bounding island area.


                    # if targetIsland[3] > (sourceIsland[2]) and\ #
                    # print USER_FREE_SPACE_TO_TEST_QUALITY, 'ass'
                    if targetIsland[2] > (sourceIsland[1] * USER_FREE_SPACE_TO_TEST_QUALITY) and\
                    targetIsland[4] > sourceIsland[4] and\
                    targetIsland[5] > sourceIsland[5]:

                        # DEBUG # print '%.10f  %.10f' % (targetIsland[3], sourceIsland[1])

                        # These enough spare space lets move the box until it fits

                        # How many times does the source fit into the target x/y
                        blockTestXUnit = targetIsland[4]/sourceIsland[4]
                        blockTestYUnit = targetIsland[5]/sourceIsland[5]

                        boxLeft = 0


                        # Distllllance we can move between whilst staying inside the targets bounds.
                        testWidth = targetIsland[4] - sourceIsland[4]
                        testHeight = targetIsland[5] - sourceIsland[5]

                        # Increment we move each test. x/y
                        xIncrement = (testWidth / (blockTestXUnit * ((USER_STEP_QUALITY/50)+0.1)))
                        yIncrement = (testHeight / (blockTestYUnit * ((USER_STEP_QUALITY/50)+0.1)))

                        # Make sure were not moving less then a 3rg of our width/height
                        if xIncrement<sourceIsland[4]/3:
                            xIncrement= sourceIsland[4]
                        if yIncrement<sourceIsland[5]/3:
                            yIncrement= sourceIsland[5]


                        boxLeft = 0 # Start 1 back so we can jump into the loop.
                        boxBottom= 0 #-yIncrement

                        ##testcount= 0

                        while boxBottom <= testHeight:
                            # Should we use this? - not needed for now.
                            #if Window.GetKeyQualifiers() & ctrl:
                            #	BREAK= True
                            #	break

                            ##testcount+=1
                            #print 'Testing intersect'
                            Intersect = islandIntersectUvIsland(sourceIsland, targetIsland, Vector((boxLeft, boxBottom)))
                            #print 'Done', Intersect
                            if Intersect == 1:  # Line intersect, dont bother with this any more
                                pass

                            if Intersect == 2:  # Source inside target
                                '''
                                We have an intersection, if we are inside the target
                                then move us 1 whole width accross,
                                Its possible this is a bad idea since 2 skinny Angular faces
                                could join without 1 whole move, but its a lot more optimal to speed this up
                                since we have already tested for it.

                                It gives about 10% speedup with minimal errors.
                                '''
                                #print 'ass'
                                # Move the test allong its width + SMALL_NUM
                                #boxLeft += sourceIsland[4] + SMALL_NUM
                                boxLeft += sourceIsland[4]
                            elif Intersect == 0: # No intersection?? Place it.
                                # Progress
                                removedCount +=1
#XXX								Window.DrawProgressBar(0.0, 'Merged: %i islands, Ctrl to finish early.' % removedCount)

                                # Move faces into new island and offset
                                targetIsland[0].extend(sourceIsland[0])
                                offset= Vector((boxLeft, boxBottom))

                                for f in sourceIsland[0]:
                                    for uv in f.uv:
                                        uv+= offset

                                sourceIsland[0][:] = [] # Empty


                                # Move edge loop into new and offset.
                                # targetIsland[6].extend(sourceIsland[6])
                                #while sourceIsland[6]:
                                targetIsland[6].extend( [ (\
                                     (e[0]+offset, e[1]+offset, e[2])\
                                ) for e in sourceIsland[6] ] )

                                sourceIsland[6][:] = [] # Empty

                                # Sort by edge length, reverse so biggest are first.

                                try:	 targetIsland[6].sort(key = lambda A: A[2])
                                except:	targetIsland[6].sort(lambda B,A: cmp(A[2], B[2] ))


                                targetIsland[7].extend(sourceIsland[7])
                                offset= Vector((boxLeft, boxBottom, 0.0))
                                for p in sourceIsland[7]:
                                    p+= offset

                                sourceIsland[7][:] = []


                                # Decrement the efficiency
                                targetIsland[1]+=sourceIsland[1] # Increment totFaceArea
                                targetIsland[2]-=sourceIsland[1] # Decrement efficiency
                                # IF we ever used these again, should set to 0, eg
                                sourceIsland[2] = 0 # No area if anyone wants to know

                                break


                            # INCREMENR NEXT LOCATION
                            if boxLeft > testWidth:
                                boxBottom += yIncrement
                                boxLeft = 0.0
                            else:
                                boxLeft += xIncrement
                        ##print testcount

                efficIslandIdx+=1
        areaIslandIdx+=1

    # Remove empty islands
    i = len(islandList)
    while i:
        i-=1
        if not islandList[i]:
            del islandList[i] # Can increment islands removed here.

# Takes groups of faces. assumes face groups are UV groups.
def getUvIslands(faceGroups, me):

    # Get seams so we dont cross over seams
    edge_seams = {} # shoudl be a set
    for ed in me.edges:
        if ed.use_seam:
            edge_seams[ed.key] = None # dummy var- use sets!
    # Done finding seams


    islandList = []

#XXX	Window.DrawProgressBar(0.0, 'Splitting %d projection groups into UV islands:' % len(faceGroups))
    #print '\tSplitting %d projection groups into UV islands:' % len(faceGroups),
    # Find grouped faces

    faceGroupIdx = len(faceGroups)

    while faceGroupIdx:
        faceGroupIdx-=1
        faces = faceGroups[faceGroupIdx]

        if not faces:
            continue

        # Build edge dict
        edge_users = {}

        for i, f in enumerate(faces):
            for ed_key in f.edge_keys:
                if ed_key in edge_seams: # DELIMIT SEAMS! ;)
                    edge_users[ed_key] = [] # so as not to raise an error
                else:
                    try:		edge_users[ed_key].append(i)
                    except:		edge_users[ed_key] = [i]

        # Modes
        # 0 - face not yet touched.
        # 1 - added to island list, and need to search
        # 2 - touched and searched - dont touch again.
        face_modes = [0] * len(faces) # initialize zero - untested.

        face_modes[0] = 1 # start the search with face 1

        newIsland = []

        newIsland.append(faces[0])


        ok = True
        while ok:

            ok = True
            while ok:
                ok= False
                for i in range(len(faces)):
                    if face_modes[i] == 1: # search
                        for ed_key in faces[i].edge_keys:
                            for ii in edge_users[ed_key]:
                                if i != ii and face_modes[ii] == 0:
                                    face_modes[ii] = ok = 1 # mark as searched
                                    newIsland.append(faces[ii])

                        # mark as searched, dont look again.
                        face_modes[i] = 2

            islandList.append(newIsland)

            ok = False
            for i in range(len(faces)):
                if face_modes[i] == 0:
                    newIsland = []
                    newIsland.append(faces[i])

                    face_modes[i] = ok = 1
                    break
            # if not ok will stop looping

#XXX	Window.DrawProgressBar(0.1, 'Optimizing Rotation for %i UV Islands' % len(islandList))

    for island in islandList:
        optiRotateUvIsland(island)

    return islandList


def packIslands(islandList):
    if USER_FILL_HOLES:
#XXX		Window.DrawProgressBar(0.1, 'Merging Islands (Ctrl: skip merge)...')
        mergeUvIslands(islandList) # Modify in place


    # Now we have UV islands, we need to pack them.

    # Make a synchronised list with the islands
    # so we can box pak the islands.
    packBoxes = []

    # Keep a list of X/Y offset so we can save time by writing the
    # uv's and packed data in one pass.
    islandOffsetList = []

    islandIdx = 0

    while islandIdx < len(islandList):
        minx, miny, maxx, maxy = boundsIsland(islandList[islandIdx])

        w, h = maxx-minx, maxy-miny

        if USER_ISLAND_MARGIN:
            minx -= USER_ISLAND_MARGIN# *w
            miny -= USER_ISLAND_MARGIN# *h
            maxx += USER_ISLAND_MARGIN# *w
            maxy += USER_ISLAND_MARGIN# *h

            # recalc width and height
            w, h = maxx-minx, maxy-miny

        if w < 0.00001 or h < 0.00001:
            del islandList[islandIdx]
            islandIdx -=1
            continue

        '''Save the offset to be applied later,
        we could apply to the UVs now and allign them to the bottom left hand area
        of the UV coords like the box packer imagines they are
        but, its quicker just to remember their offset and
        apply the packing and offset in 1 pass '''
        islandOffsetList.append((minx, miny))

        # Add to boxList. use the island idx for the BOX id.
        packBoxes.append([0, 0, w, h])
        islandIdx+=1

    # Now we have a list of boxes to pack that syncs
    # with the islands.

    #print '\tPacking UV Islands...'
#XXX	Window.DrawProgressBar(0.7, 'Packing %i UV Islands...' % len(packBoxes) )

    time1 = time.time()
    packWidth, packHeight = geometry.BoxPack2D(packBoxes)

    # print 'Box Packing Time:', time.time() - time1

    #if len(pa	ckedLs) != len(islandList):
    #	raise "Error packed boxes differes from original length"

    #print '\tWriting Packed Data to faces'
#XXX	Window.DrawProgressBar(0.8, 'Writing Packed Data to faces')

    # Sort by ID, so there in sync again
    islandIdx = len(islandList)
    # Having these here avoids devide by 0
    if islandIdx:

        if USER_STRETCH_ASPECT:
            # Maximize to uv area?? Will write a normalize function.
            xfactor = 1.0 / packWidth
            yfactor = 1.0 / packHeight
        else:
            # Keep proportions.
            xfactor = yfactor = 1.0 / max(packWidth, packHeight)

    while islandIdx:
        islandIdx -=1
        # Write the packed values to the UV's

        xoffset = packBoxes[islandIdx][0] - islandOffsetList[islandIdx][0]
        yoffset = packBoxes[islandIdx][1] - islandOffsetList[islandIdx][1]

        for f in islandList[islandIdx]: # Offsetting the UV's so they fit in there packed box
            for uv in f.uv:
                uv.x= (uv.x+xoffset) * xfactor
                uv.y= (uv.y+yoffset) * yfactor



def VectoMat(vec):
    a3 = vec.__copy__().normalize()

    up = Vector((0.0, 0.0, 1.0))
    if abs(a3.dot(up)) == 1.0:
        up = Vector((0.0, 1.0, 0.0))

    a1 = a3.cross(up).normalize()
    a2 = a3.cross(a1)
    return Matrix([a1[0], a1[1], a1[2]], [a2[0], a2[1], a2[2]], [a3[0], a3[1], a3[2]])


class thickface(object):
    __slost__= 'v', 'uv', 'no', 'area', 'edge_keys'
    def __init__(self, face, uvface, mesh_verts):
        self.v = [mesh_verts[i] for i in face.vertices]
        if len(self.v)==4:
            self.uv = uvface.uv1, uvface.uv2, uvface.uv3, uvface.uv4
        else:
            self.uv = uvface.uv1, uvface.uv2, uvface.uv3

        self.no = face.normal
        self.area = face.area
        self.edge_keys = face.edge_keys

global ob
ob = None
def main(context, island_margin, projection_limit):
    global USER_FILL_HOLES
    global USER_FILL_HOLES_QUALITY
    global USER_STRETCH_ASPECT
    global USER_ISLAND_MARGIN

#XXX objects= bpy.data.scenes.active.objects
    objects = context.selected_editable_objects


    # we can will tag them later.
    obList =  [ob for ob in objects if ob.type == 'MESH']

    # Face select object may not be selected.
#XXX	ob = objects.active
    ob= objects[0]

    if ob and (not ob.select) and ob.type == 'MESH':
        # Add to the list
        obList =[ob]
    del objects

    if not obList:
        raise('error, no selected mesh objects')

    # Create the variables.
    USER_PROJECTION_LIMIT = projection_limit
    USER_ONLY_SELECTED_FACES = (1)
    USER_SHARE_SPACE = (1) # Only for hole filling.
    USER_STRETCH_ASPECT = (1) # Only for hole filling.
    USER_ISLAND_MARGIN = island_margin # Only for hole filling.
    USER_FILL_HOLES = (0)
    USER_FILL_HOLES_QUALITY = (50) # Only for hole filling.
    USER_VIEW_INIT = (0) # Only for hole filling.
    USER_AREA_WEIGHT = (1) # Only for hole filling.

    # Reuse variable
    if len(obList) == 1:
        ob = "Unwrap %i Selected Mesh"
    else:
        ob = "Unwrap %i Selected Meshes"

    # HACK, loop until mouse is lifted.
    '''
    while Window.GetMouseButtons() != 0:
        time.sleep(10)
    '''

#XXX	if not Draw.PupBlock(ob % len(obList), pup_block):
#XXX		return
#XXX	del ob

    # Convert from being button types

    USER_PROJECTION_LIMIT_CONVERTED = cos(USER_PROJECTION_LIMIT * DEG_TO_RAD)
    USER_PROJECTION_LIMIT_HALF_CONVERTED = cos((USER_PROJECTION_LIMIT/2) * DEG_TO_RAD)


    # Toggle Edit mode
    is_editmode = (context.active_object.mode == 'EDIT')
    if is_editmode:
        bpy.ops.object.mode_set(mode='OBJECT')
    # Assume face select mode! an annoying hack to toggle face select mode because Mesh dosent like faceSelectMode.

    if USER_SHARE_SPACE:
        # Sort by data name so we get consistant results
        obList.sort(key = lambda ob: ob.data.name)
        collected_islandList= []

#XXX	Window.WaitCursor(1)

    time1 = time.time()

    # Tag as False se we dont operate on teh same mesh twice.
#XXX	bpy.data.meshes.tag = False
    for me in bpy.data.meshes:
        me.tag = False


    for ob in obList:
        me = ob.data

        if me.tag or me.library:
            continue

        # Tag as used
        me.tag = True

        if not me.uv_textures: # Mesh has no UV Coords, dont bother.
            me.uv_textures.new()

        uv_layer = me.uv_textures.active.data
        me_verts = list(me.vertices)

        if USER_ONLY_SELECTED_FACES:
            meshFaces = [thickface(f, uv_layer[i], me_verts) for i, f in enumerate(me.faces) if f.select]
        #else:
        #	meshFaces = map(thickface, me.faces)

        if not meshFaces:
            continue

#XXX		Window.DrawProgressBar(0.1, 'SmartProj UV Unwrapper, mapping "%s", %i faces.' % (me.name, len(meshFaces)))

        # =======
        # Generate a projection list from face normals, this is ment to be smart :)

        # make a list of face props that are in sync with meshFaces
        # Make a Face List that is sorted by area.
        # meshFaces = []

        # meshFaces.sort( lambda a, b: cmp(b.area , a.area) ) # Biggest first.
        meshFaces.sort( key = lambda a: -a.area )

        # remove all zero area faces
        while meshFaces and meshFaces[-1].area <= SMALL_NUM:
            # Set their UV's to 0,0
            for uv in meshFaces[-1].uv:
                uv.zero()
            meshFaces.pop()

        # Smallest first is slightly more efficient, but if the user cancels early then its better we work on the larger data.

        # Generate Projection Vecs
        # 0d is   1.0
        # 180 IS -0.59846


        # Initialize projectVecs
        if USER_VIEW_INIT:
            # Generate Projection
            projectVecs = [Vector(Window.GetViewVector()) * ob.matrix_world.copy().invert().rotation_part()] # We add to this allong the way
        else:
            projectVecs = []

        newProjectVec = meshFaces[0].no
        newProjectMeshFaces = []	# Popping stuffs it up.


        # Predent that the most unique angke is ages away to start the loop off
        mostUniqueAngle = -1.0

        # This is popped
        tempMeshFaces = meshFaces[:]



        # This while only gathers projection vecs, faces are assigned later on.
        while 1:
            # If theres none there then start with the largest face

            # add all the faces that are close.
            for fIdx in range(len(tempMeshFaces)-1, -1, -1):
                # Use half the angle limit so we dont overweight faces towards this
                # normal and hog all the faces.
                if newProjectVec.dot(tempMeshFaces[fIdx].no) > USER_PROJECTION_LIMIT_HALF_CONVERTED:
                    newProjectMeshFaces.append(tempMeshFaces.pop(fIdx))

            # Add the average of all these faces normals as a projectionVec
            averageVec = Vector((0.0, 0.0, 0.0))
            if USER_AREA_WEIGHT:
                for fprop in newProjectMeshFaces:
                    averageVec += (fprop.no * fprop.area)
            else:
                for fprop in newProjectMeshFaces:
                    averageVec += fprop.no

            if averageVec.x != 0 or averageVec.y != 0 or averageVec.z != 0: # Avoid NAN
                projectVecs.append(averageVec.normalize())


            # Get the next vec!
            # Pick the face thats most different to all existing angles :)
            mostUniqueAngle = 1.0 # 1.0 is 0d. no difference.
            mostUniqueIndex = 0 # dummy

            for fIdx in range(len(tempMeshFaces)-1, -1, -1):
                angleDifference = -1.0 # 180d difference.

                # Get the closest vec angle we are to.
                for p in projectVecs:
                    temp_angle_diff= p.dot(tempMeshFaces[fIdx].no)

                    if angleDifference < temp_angle_diff:
                        angleDifference= temp_angle_diff

                if angleDifference < mostUniqueAngle:
                    # We have a new most different angle
                    mostUniqueIndex = fIdx
                    mostUniqueAngle = angleDifference

            if mostUniqueAngle < USER_PROJECTION_LIMIT_CONVERTED:
                #print 'adding', mostUniqueAngle, USER_PROJECTION_LIMIT, len(newProjectMeshFaces)
                # Now weight the vector to all its faces, will give a more direct projection
                # if the face its self was not representive of the normal from surrounding faces.