share/extensions/straightseg.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 math, inkex, simplepath, sys
  20
  21 def pointAtPercent((x1, y1), (x2, y2), percent):
  22     percent /= 100.0
  23     x = x1 + (percent * (x2 - x1))
  24     y = y1 + (percent * (y2 - y1))
  25     return [x,y]
  26
  27 class SegmentStraightener(inkex.Effect):
  28     def __init__(self):
  29         inkex.Effect.__init__(self)
  30         self.OptionParser.add_option("-p", "--percent",
  31                         action="store", type="float",
  32                         dest="percent", default=10.0,
  33                         help="move curve handles PERCENT percent closer to a straight line")
  34         self.OptionParser.add_option("-b", "--behavior",
  35                         action="store", type="int",
  36                         dest="behave", default=1,
  37                         help="straightening behavior for cubic segments")
  38     def effect(self):
  39         for id, node in self.selected.iteritems():
  40             if node.tag == inkex.addNS('path', 'svg'):
  41                 d = node.get('d')
  42                 p = simplepath.parsePath(d)
  43                 last = []
  44                 subPathStart = []
  45                 for cmd,params in p:
  46                     if cmd == 'C':
  47                         if self.options.behave <= 1:
  48                             #shorten handles towards end points
  49                             params[:2] = pointAtPercent(params[:2],last[:],self.options.percent)
  50                             params[2:4] = pointAtPercent(params[2:4],params[-2:],self.options.percent)
  51                         else:
  52                             #shorten handles towards thirds of the segment
  53                             dest1 = pointAtPercent(last[:],params[-2:],33.3)
  54                             dest2 = pointAtPercent(params[-2:],last[:],33.3)
  55                             params[:2] = pointAtPercent(params[:2],dest1[:],self.options.percent)
  56                             params[2:4] = pointAtPercent(params[2:4],dest2[:],self.options.percent)
  57                     elif cmd == 'Q':
  58                         dest = pointAtPercent(last[:],params[-2:],50)
  59                         params[:2] = pointAtPercent(params[:2],dest,self.options.percent)
  60                     if cmd == 'M':
  61                         subPathStart = params[-2:]
  62                     if cmd == 'Z':
  63                         last = subPathStart[:]
  64                     else:
  65                         last = params[-2:]
  66                 node.set('d',simplepath.formatPath(p))
  67
  68 if __name__ == '__main__':
  69     e = SegmentStraightener()
  70     e.affect()
  71
  72
  73 # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99