share/extensions/lindenmayer.py

   1 #!/usr/bin/env python
   2 '''
   3 Copyright (C) 2005 Aaron Spike, aaron@ekips.org
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 '''
  19 import inkex, simplestyle, pturtle, random
  20
  21 def stripme(s):
  22     return s.strip()
  23
  24 class LSystem(inkex.Effect):
  25     def __init__(self):
  26         inkex.Effect.__init__(self)
  27         self.OptionParser.add_option("-o", "--order",
  28                         action="store", type="int",
  29                         dest="order", default=3,
  30                         help="number of iteration")
  31         self.OptionParser.add_option("-l", "--langle",
  32                         action="store", type="float",
  33                         dest="langle", default=16.0,
  34                         help="angle for turning left")
  35         self.OptionParser.add_option("-r", "--rangle",
  36                         action="store", type="float",
  37                         dest="rangle", default=16.0,
  38                         help="angle for turning right")
  39         self.OptionParser.add_option("-s", "--step",
  40                         action="store", type="float",
  41                         dest="step", default=25.0,
  42                         help="step size")
  43         self.OptionParser.add_option("-p", "--randomizestep",
  44                         action="store", type="float",
  45                         dest="randomizestep", default=0.0,
  46                         help="randomize step")
  47         self.OptionParser.add_option("-z", "--randomizeangle",
  48                         action="store", type="float",
  49                         dest="randomizeangle", default=0.0,
  50                         help="randomize angle")
  51         self.OptionParser.add_option("-x", "--axiom",
  52                         action="store", type="string",
  53                         dest="axiom", default="++F",
  54                         help="initial state of system")
  55         self.OptionParser.add_option("-u", "--rules",
  56                         action="store", type="string",
  57                         dest="rules", default="F=FF-[-F+F+F]+[+F-F-F]",
  58                         help="replacement rules")
  59         self.OptionParser.add_option("-t", "--tab",
  60                         action="store", type="string",
  61                         dest="tab")
  62         self.stack = []
  63         self.turtle = pturtle.pTurtle()
  64     def iterate(self):
  65         self.rules = dict([map(stripme, i.split("=")) for i in self.options.rules.upper().split(";") if i.count("=")==1])
  66         string = self.__recurse(self.options.axiom.upper(),0)
  67         self.__compose_path(string)
  68         return self.turtle.getPath()
  69     def __compose_path(self, string):
  70         self.turtle.pu()
  71         self.turtle.setpos(self.view_center)
  72         self.turtle.pd()
  73         for c in string:
  74             if c in 'ABCDEF':
  75                 self.turtle.pd()
  76                 self.turtle.fd(self.options.step * (random.normalvariate(1.0, 0.01 * self.options.randomizestep)))
  77             elif c in 'GHIJKL':
  78                 self.turtle.pu()
  79                 self.turtle.fd(self.options.step * (random.normalvariate(1.0,  0.01 * self.options.randomizestep)))
  80             elif c == '+':
  81                 self.turtle.lt(self.options.langle * (random.normalvariate(1.0,  0.01 * self.options.randomizeangle)))
  82             elif c == '-':
  83                 self.turtle.rt(self.options.rangle * (random.normalvariate(1.0,  0.01 * self.options.randomizeangle)))
  84             elif c == '|':
  85                 self.turtle.lt(180)
  86             elif c == '[':
  87                 self.stack.append([self.turtle.getpos(), self.turtle.getheading()])
  88             elif c == ']':
  89                 self.turtle.pu()
  90                 pos,heading = self.stack.pop()
  91                 self.turtle.setpos(pos)
  92                 self.turtle.setheading(heading)
  93
  94     def __recurse(self,rule,level):
  95         level_string = ''
  96         for c in rule:
  97             if level < self.options.order:
  98                 try:
  99                     level_string = level_string + self.__recurse(self.rules[c],level+1)
 100                 except KeyError:
 101                     level_string = level_string + c
 102             else:
 103                 level_string = level_string + c
 104         return level_string
 105
 106     def effect(self):
 107         s = {'stroke-linejoin': 'miter', 'stroke-width': '1.0px',
 108             'stroke-opacity': '1.0', 'fill-opacity': '1.0',
 109             'stroke': '#000000', 'stroke-linecap': 'butt',
 110             'fill': 'none'}
 111         attribs = {'style':simplestyle.formatStyle(s),'d':self.iterate()}
 112         inkex.etree.SubElement(self.current_layer,inkex.addNS('path','svg'),attribs)
 113
 114 if __name__ == '__main__':
 115     e = LSystem()
 116     e.affect()
 117
 118
 119 # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99