share/extensions/measure.py

   1 #!/usr/bin/env python
   2 '''
   3 Copyright (C) 2006 Nathan Hurst
   4 Copyright (C) 2005 Aaron Spike, aaron@ekips.org
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 '''
  20 import inkex, simplestyle, simplepath,sys,cubicsuperpath, bezmisc
  21
  22 def numsegs(csp):
  23     return sum([len(p)-1 for p in csp])
  24 def interpcoord(v1,v2,p):
  25     return v1+((v2-v1)*p)
  26 def interppoints(p1,p2,p):
  27     return [interpcoord(p1[0],p2[0],p),interpcoord(p1[1],p2[1],p)]
  28 def pointdistance((x1,y1),(x2,y2)):
  29     return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))
  30 def bezlenapprx(sp1, sp2):
  31     return pointdistance(sp1[1], sp1[2]) + pointdistance(sp1[2], sp2[0]) + pointdistance(sp2[0], sp2[1])
  32 def tpoint((x1,y1), (x2,y2), t = 0.5):
  33     return [x1+t*(x2-x1),y1+t*(y2-y1)]
  34 def cspbezsplit(sp1, sp2, t = 0.5):
  35     m1=tpoint(sp1[1],sp1[2],t)
  36     m2=tpoint(sp1[2],sp2[0],t)
  37     m3=tpoint(sp2[0],sp2[1],t)
  38     m4=tpoint(m1,m2,t)
  39     m5=tpoint(m2,m3,t)
  40     m=tpoint(m4,m5,t)
  41     return [[sp1[0][:],sp1[1][:],m1], [m4,m,m5], [m3,sp2[1][:],sp2[2][:]]]
  42 def cspbezsplitatlength(sp1, sp2, l = 0.5, tolerance = 0.001):
  43     bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
  44     t = bezmisc.beziertatlength(bez, l, tolerance)
  45     return cspbezsplit(sp1, sp2, t)
  46 def cspseglength(sp1,sp2, tolerance = 0.001):
  47     bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
  48     return bezmisc.bezierlength(bez, tolerance)
  49 def csplength(csp):
  50     total = 0
  51     lengths = []
  52     for sp in csp:
  53         lengths.append([])
  54         for i in xrange(1,len(sp)):
  55             l = cspseglength(sp[i-1],sp[i])
  56             lengths[-1].append(l)
  57             total += l
  58     return lengths, total
  59
  60 class Length(inkex.Effect):
  61     def __init__(self):
  62         inkex.Effect.__init__(self)
  63         self.OptionParser.add_option("-f", "--fontsize",
  64                         action="store", type="string",
  65                         dest="fontsize", default="20",
  66                         help="Size of node label numbers")
  67         self.OptionParser.add_option("-o", "--offset",
  68                         action="store", type="string",
  69                         dest="offset", default="-4",
  70                         help="The distance above the curve")
  71     def effect(self):
  72         for id, node in self.selected.iteritems():
  73             if node.tagName == 'path':
  74                 self.group = self.document.createElement('svg:g')
  75                 node.parentNode.appendChild(self.group)
  76
  77                 try:
  78                     t = node.attributes.getNamedItem('transform').value
  79                     self.group.setAttribute('transform', t)
  80                 except AttributeError:
  81                     pass
  82
  83                 a =[]
  84                 p = cubicsuperpath.parsePath(node.attributes.getNamedItem('d').value)
  85                 num = 1
  86                 slengths, stotal = csplength(p)
  87                 self.addTextOnPath(self.group,0, 0,str(stotal), id, self.options.offset)
  88
  89
  90     def addTextOnPath(self,node,x,y,text, id,dy=0):
  91                 new = self.document.createElement('svg:text')
  92                 tp = self.document.createElement('svg:textPath')
  93                 s = {'font-size': self.options.fontsize, 'fill-opacity': '1.0', 'stroke': 'none',
  94                     'font-weight': 'normal', 'font-style': 'normal', 'fill': '#000000'}
  95                 new.setAttribute('style', simplestyle.formatStyle(s))
  96                 new.setAttribute('x', str(x))
  97                 new.setAttribute('y', str(y))
  98                 tp.setAttributeNS('http://www.w3.org/1999/xlink','xlink:href', '#'+id)
  99                 tp.setAttribute('startOffset', "50%")
 100                 #tp.setAttribute('dy', dy) # dubious merit
 101                 new.appendChild(tp)
 102                 tp.appendChild(self.document.createTextNode(str(text)))
 103                 node.appendChild(new)
 104
 105 e = Length()
 106 e.affect()