#!/usr/bin/env python ''' Copyright (C) 2005 Carsten Goetze c.goetze@tu-bs.de 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. ''' import random, math, inkex, simplepath def calculateSubdivision(x1,y1,x2,y2,smoothness): """ Calculate the vector from (x1,y1) to (x2,y2) """ x3 = x2 - x1 y3 = y2 - y1 """ Calculate the point half-way between the two points """ hx = x1 + x3/2 hy = y1 + y3/2 """ Calculate normalized vector perpendicular to the vector (x3,y3) """ length = math.sqrt(x3*x3 + y3*y3) if length != 0: nx = -y3/length ny = x3/length else: nx = 1 ny = 0 """ Scale perpendicular vector by random factor """ r = random.uniform(-length/(1+smoothness),length/(1+smoothness)) nx = nx * r ny = ny * r """ add scaled perpendicular vector to the half-way point to get the final displaced subdivision point """ x = hx + nx y = hy + ny return [x, y] class PathFractalize(inkex.Effect): def __init__(self): inkex.Effect.__init__(self) self.OptionParser.add_option("-s", "--subdivs", action="store", type="int", dest="subdivs", default="6", help="Number of subdivisons") self.OptionParser.add_option("-f", "--smooth", action="store", type="float", dest="smooth", default="4.0", help="Smoothness of the subdivision") def effect(self): for id, node in self.selected.items(): if node.tag == inkex.addNS('path','svg'): d = node.get('d') p = simplepath.parsePath(d) a = [] first = 1 for cmd,params in p: if cmd != 'Z': if first == 1: x1 = params[-2] y1 = params[-1] a.append(['M',params[-2:]]) first = 2 else : x2 = params[-2] y2 = params[-1] self.fractalize(a,x1,y1,x2,y2,self.options.subdivs,self.options.smooth) x1 = x2 y1 = y2 a.append(['L',params[-2:]]) node.set('d', simplepath.formatPath(a)) def fractalize(self,a,x1,y1,x2,y2,s,f): subdivPoint = calculateSubdivision(x1,y1,x2,y2,f) if s > 0 : """ recursively subdivide the segment left of the subdivision point """ self.fractalize(a,x1,y1,subdivPoint[-2],subdivPoint[-1],s-1,f) a.append(['L',subdivPoint]) """ recursively subdivide the segment right of the subdivision point """ self.fractalize(a,subdivPoint[-2],subdivPoint[-1],x2,y2,s-1,f) if __name__ == '__main__': e = PathFractalize() e.affect() # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99