import inkex, cubicsuperpath, bezmisc, simplestyle

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)

class SplitIt(inkex.Effect):

def __init__(self):

inkex.Effect.__init__(self)

def effect(self):

for id, node in self.selected.iteritems():

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

dashes = []

style = simplestyle.parseStyle(node.get('style'))

if style.has_key('stroke-dasharray'):

if style['stroke-dasharray'].find(',') > 0:

dashes = [float (dash) for dash in style['stroke-dasharray'].split(',')]

if dashes:

p = cubicsuperpath.parsePath(node.get('d'))

new = []

for sub in p:

idash = 0

dash = dashes[0]

length = 0

new.append([sub[0][:]])

i = 1

while i < len(sub):

dash = dash - length

length = cspseglength(new[-1][-1], sub[i])

while dash < length:

new[-1][-1], next, sub[i] = cspbezsplitatlength(new[-1][-1], sub[i], dash/length)

if idash % 2: # create a gap

new.append([next[:]])

else: # splice the curve

new[-1].append(next[:])

length = length - dash

idash = (idash + 1) % len(dashes)

dash = dashes[idash]

if idash % 2:

new.append([sub[i]])

else:

new[-1].append(sub[i])

i+=1

node.set('d',cubicsuperpath.formatPath(new))

del style['stroke-dasharray']

node.set('style', simplestyle.formatStyle(style))

if __name__ == '__main__':

e = SplitIt()

e.affect()