import inkex, cubicsuperpath, simplestyle, copy, math, bezmisc

def numsegs(csp):

return sum([len(p)-1 for p in csp])

def interpcoord(v1,v2,p):

return v1+((v2-v1)*p)

def interppoints(p1,p2,p):

return [interpcoord(p1[0],p2[0],p),interpcoord(p1[1],p2[1],p)]

def pointdistance((x1,y1),(x2,y2)):

return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))

def bezlenapprx(sp1, sp2):

return pointdistance(sp1[1], sp1[2]) + pointdistance(sp1[2], sp2[0]) + pointdistance(sp2[0], sp2[1])

def tpoint((x1,y1), (x2,y2), t = 0.5):

return [x1+t*(x2-x1),y1+t*(y2-y1)]

def cspbezsplit(sp1, sp2, t = 0.5):

m1=tpoint(sp1[1],sp1[2],t)

m2=tpoint(sp1[2],sp2[0],t)

m3=tpoint(sp2[0],sp2[1],t)

m4=tpoint(m1,m2,t)

m5=tpoint(m2,m3,t)

m=tpoint(m4,m5,t)

return [[sp1[0][:],sp1[1][:],m1], [m4,m,m5], [m3,sp2[1][:],sp2[2][:]]]

def cspbezsplitatlength(sp1, sp2, l = 0.5, tolerance = 0.001):

bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])

t = bezmisc.beziertatlength(bez, l, tolerance)

return cspbezsplit(sp1, sp2, t)

def cspseglength(sp1,sp2, tolerance = 0.001):

bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])

return bezmisc.bezierlength(bez, tolerance)

def csplength(csp):

total = 0

lengths = []

for sp in csp:

lengths.append([])

for i in xrange(1,len(sp)):

l = cspseglength(sp[i-1],sp[i])

lengths[-1].append(l)

total += l

return lengths, total

def tweenstylefloat(property, start, end, time):

sp = float(start[property])

ep = float(end[property])

return str(sp + (time * (ep - sp)))

def tweenstyleunit(property, start, end, time):

sp = inkex.unittouu(start[property])

ep = inkex.unittouu(end[property])

return str(sp + (time * (ep - sp)))

def tweenstylecolor(property, start, end, time):

sr,sg,sb = parsecolor(start[property])

er,eg,eb = parsecolor(end[property])

return '#%s%s%s' % (tweenhex(time,sr,er),tweenhex(time,sg,eg),tweenhex(time,sb,eb))

def tweenhex(time,s,e):

s = float(int(s,16))

e = float(int(e,16))

retval = hex(int(math.floor(s + (time * (e - s)))))[2:]

if len(retval)==1:

retval = '0%s' % retval

return retval

def parsecolor(c):

r,g,b = '0','0','0'

if c[:1]=='#':

if len(c)==4:

r,g,b = c[1:2],c[2:3],c[3:4]

elif len(c)==7:

r,g,b = c[1:3],c[3:5],c[5:7]

return r,g,b

class Interp(inkex.Effect):

def __init__(self):

inkex.Effect.__init__(self)

self.OptionParser.add_option("-e", "--exponent",

action="store", type="float",

dest="exponent", default=0.0,

help="values other than zero give non linear interpolation")

self.OptionParser.add_option("-s", "--steps",

action="store", type="int",

dest="steps", default=5,

help="number of interpolation steps")

self.OptionParser.add_option("-m", "--method",

action="store", type="int",

dest="method", default=2,

help="method of interpolation")

self.OptionParser.add_option("-d", "--dup",

action="store", type="inkbool",

dest="dup", default=True,

help="duplicate endpaths")

self.OptionParser.add_option("--style",

action="store", type="inkbool",

dest="style", default=True,

help="try interpolation of some style properties")

def effect(self):

exponent = self.options.exponent

if exponent>= 0:

exponent = 1.0 + exponent

else:

exponent = 1.0/(1.0 - exponent)

steps = [1.0/(self.options.steps + 1.0)]

for i in range(self.options.steps - 1):

steps.append(steps[0] + steps[-1])

steps = [step**exponent for step in steps]

paths = {}

styles = {}

for id in self.options.ids:

node = self.selected[id]

if node.tag ==inkex.addNS('path','svg'):

paths[id] = cubicsuperpath.parsePath(node.get('d'))

styles[id] = simplestyle.parseStyle(node.get('style'))

else:

self.options.ids.remove(id)

for i in range(1,len(self.options.ids)):

start = copy.deepcopy(paths[self.options.ids[i-1]])

end = copy.deepcopy(paths[self.options.ids[i]])

sst = copy.deepcopy(styles[self.options.ids[i-1]])

est = copy.deepcopy(styles[self.options.ids[i]])

basestyle = copy.deepcopy(sst)

#prepare for experimental style tweening

if self.options.style:

dostroke = True

dofill = True

styledefaults = {'opacity':'1.0', 'stroke-opacity':'1.0', 'fill-opacity':'1.0',

'stroke-width':'1.0', 'stroke':'none', 'fill':'none'}

for key in styledefaults.keys():

sst.setdefault(key,styledefaults[key])

est.setdefault(key,styledefaults[key])

isnotplain = lambda x: not (x=='none' or x[:1]=='#')

if isnotplain(sst['stroke']) or isnotplain(est['stroke']) or (sst['stroke']=='none' and est['stroke']=='none'):

dostroke = False

if isnotplain(sst['fill']) or isnotplain(est['fill']) or (sst['fill']=='none' and est['fill']=='none'):

dofill = False

if dostroke:

if sst['stroke']=='none':

sst['stroke-width'] = '0.0'

sst['stroke-opacity'] = '0.0'

sst['stroke'] = est['stroke']

elif est['stroke']=='none':

est['stroke-width'] = '0.0'

est['stroke-opacity'] = '0.0'

est['stroke'] = sst['stroke']

if dofill:

if sst['fill']=='none':

sst['fill-opacity'] = '0.0'

sst['fill'] = est['fill']

elif est['fill']=='none':

est['fill-opacity'] = '0.0'

est['fill'] = sst['fill']

if self.options.method == 2:

#subdivide both paths into segments of relatively equal lengths

slengths, stotal = csplength(start)

elengths, etotal = csplength(end)

lengths = {}

t = 0

for sp in slengths:

for l in sp:

t += l / stotal

lengths.setdefault(t,0)

lengths[t] += 1

t = 0

for sp in elengths:

for l in sp:

t += l / etotal

lengths.setdefault(t,0)

lengths[t] += -1

sadd = [k for (k,v) in lengths.iteritems() if v < 0]

sadd.sort()

eadd = [k for (k,v) in lengths.iteritems() if v > 0]

eadd.sort()

t = 0

s = [[]]

for sp in slengths:

if not start[0]:

s.append(start.pop(0))

s[-1].append(start[0].pop(0))

for l in sp:

pt = t

t += l / stotal

if sadd and t > sadd[0]:

while sadd and sadd[0] < t:

nt = (sadd[0] - pt) / (t - pt)

bezes = cspbezsplitatlength(s[-1][-1][:],start[0][0][:], nt)

s[-1][-1:] = bezes[:2]

start[0][0] = bezes[2]

pt = sadd.pop(0)

s[-1].append(start[0].pop(0))

t = 0

e = [[]]

for sp in elengths:

if not end[0]:

e.append(end.pop(0))

e[-1].append(end[0].pop(0))

for l in sp:

pt = t

t += l / etotal

if eadd and t > eadd[0]:

while eadd and eadd[0] < t:

nt = (eadd[0] - pt) / (t - pt)

bezes = cspbezsplitatlength(e[-1][-1][:],end[0][0][:], nt)

e[-1][-1:] = bezes[:2]

end[0][0] = bezes[2]

pt = eadd.pop(0)

e[-1].append(end[0].pop(0))

start = s[:]

end = e[:]

else:

#which path has fewer segments?

lengthdiff = numsegs(start) - numsegs(end)

#swap shortest first

if lengthdiff > 0:

start, end = end, start

#subdivide the shorter path

for x in range(abs(lengthdiff)):

maxlen = 0

subpath = 0

segment = 0

for y in range(len(start)):

for z in range(1, len(start[y])):

leng = bezlenapprx(start[y][z-1], start[y][z])

if leng > maxlen:

maxlen = leng

subpath = y

segment = z

sp1, sp2 = start[subpath][segment - 1:segment + 1]

start[subpath][segment - 1:segment + 1] = cspbezsplit(sp1, sp2)

#if swapped, swap them back

if lengthdiff > 0:

start, end = end, start

#break paths so that corresponding subpaths have an equal number of segments

s = [[]]

e = [[]]

while start and end:

if start[0] and end[0]:

s[-1].append(start[0].pop(0))

e[-1].append(end[0].pop(0))

elif end[0]:

s.append(start.pop(0))

e[-1].append(end[0][0])

e.append([end[0].pop(0)])

elif start[0]:

e.append(end.pop(0))

s[-1].append(start[0][0])

s.append([start[0].pop(0)])

else:

s.append(start.pop(0))

e.append(end.pop(0))

if self.options.dup:

steps = [0] + steps + [1]

#create an interpolated path for each interval

group = inkex.etree.SubElement(self.current_layer,inkex.addNS('g','svg'))

for time in steps:

interp = []

#process subpaths

for ssp,esp in zip(s, e):

if not (ssp or esp):

break

interp.append([])

#process superpoints

for sp,ep in zip(ssp, esp):

if not (sp or ep):

break

interp[-1].append([])

#process points

for p1,p2 in zip(sp, ep):

if not (sp or ep):

break

interp[-1][-1].append(interppoints(p1, p2, time))

#remove final subpath if empty.

if not interp[-1]:

del interp[-1]

#basic style tweening

if self.options.style:

basestyle['opacity'] = tweenstylefloat('opacity',sst,est,time)

if dostroke:

basestyle['stroke-opacity'] = tweenstylefloat('stroke-opacity',sst,est,time)

basestyle['stroke-width'] = tweenstyleunit('stroke-width',sst,est,time)

basestyle['stroke'] = tweenstylecolor('stroke',sst,est,time)

if dofill:

basestyle['fill-opacity'] = tweenstylefloat('fill-opacity',sst,est,time)

basestyle['fill'] = tweenstylecolor('fill',sst,est,time)

attribs = {'style':simplestyle.formatStyle(basestyle),'d':cubicsuperpath.formatPath(interp)}

new = inkex.etree.SubElement(group,inkex.addNS('path','svg'), attribs)

if __name__ == '__main__':

e = Interp()

e.affect()