share/extensions/measure.py

   1 #!/usr/bin/env python
   2 '''
   3 This extension module can measure arbitrary path and object length
   4 It adds a text to the selected path containing the length in a
   5 given unit.
   6
   7 Copyright (C) 2006 Georg Wiora
   8 Copyright (C) 2006 Nathan Hurst
   9 Copyright (C) 2005 Aaron Spike, aaron@ekips.org
  10
  11 This program is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU General Public License as published by
  13 the Free Software Foundation; either version 2 of the License, or
  14 (at your option) any later version.
  15
  16 This program is distributed in the hope that it will be useful,
  17 but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 GNU General Public License for more details.
  20
  21 You should have received a copy of the GNU General Public License
  22 along with this program; if not, write to the Free Software
  23 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24
  25 TODO:
  26  * should use the standard attributes for text
  27  * Implement option to keep text orientation upright
  28     1. Find text direction i.e. path tangent,
  29     2. check direction >90 or <-90 Degrees
  30     3. rotate by 180 degrees around text center
  31 '''
  32 import inkex, simplestyle, simplepath,sys,cubicsuperpath, bezmisc, locale
  33 # Set current system locale
  34 locale.setlocale(locale.LC_ALL, '')
  35
  36 def numsegs(csp):
  37     return sum([len(p)-1 for p in csp])
  38 def interpcoord(v1,v2,p):
  39     return v1+((v2-v1)*p)
  40 def interppoints(p1,p2,p):
  41     return [interpcoord(p1[0],p2[0],p),interpcoord(p1[1],p2[1],p)]
  42 def pointdistance((x1,y1),(x2,y2)):
  43     return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))
  44 def bezlenapprx(sp1, sp2):
  45     return pointdistance(sp1[1], sp1[2]) + pointdistance(sp1[2], sp2[0]) + pointdistance(sp2[0], sp2[1])
  46 def tpoint((x1,y1), (x2,y2), t = 0.5):
  47     return [x1+t*(x2-x1),y1+t*(y2-y1)]
  48 def cspbezsplit(sp1, sp2, t = 0.5):
  49     m1=tpoint(sp1[1],sp1[2],t)
  50     m2=tpoint(sp1[2],sp2[0],t)
  51     m3=tpoint(sp2[0],sp2[1],t)
  52     m4=tpoint(m1,m2,t)
  53     m5=tpoint(m2,m3,t)
  54     m=tpoint(m4,m5,t)
  55     return [[sp1[0][:],sp1[1][:],m1], [m4,m,m5], [m3,sp2[1][:],sp2[2][:]]]
  56 def cspbezsplitatlength(sp1, sp2, l = 0.5, tolerance = 0.001):
  57     bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
  58     t = bezmisc.beziertatlength(bez, l, tolerance)
  59     return cspbezsplit(sp1, sp2, t)
  60 def cspseglength(sp1,sp2, tolerance = 0.001):
  61     bez = (sp1[1][:],sp1[2][:],sp2[0][:],sp2[1][:])
  62     return bezmisc.bezierlength(bez, tolerance)
  63 def csplength(csp):
  64     total = 0
  65     lengths = []
  66     for sp in csp:
  67         lengths.append([])
  68         for i in xrange(1,len(sp)):
  69             l = cspseglength(sp[i-1],sp[i])
  70             lengths[-1].append(l)
  71             total += l
  72     return lengths, total
  73
  74 class Length(inkex.Effect):
  75     def __init__(self):
  76         inkex.Effect.__init__(self)
  77         self.OptionParser.add_option("-f", "--fontsize",
  78                         action="store", type="int",
  79                         dest="fontsize", default=20,
  80                         help="Size of length lable text in px")
  81         self.OptionParser.add_option("-o", "--offset",
  82                         action="store", type="float",
  83                         dest="offset", default=-6,
  84                         help="The distance above the curve")
  85         self.OptionParser.add_option("-u", "--unit",
  86                         action="store", type="string",
  87                         dest="unit", default="mm",
  88                         help="The unit of the measurement")
  89         self.OptionParser.add_option("-p", "--precision",
  90                         action="store", type="int",
  91                         dest="precision", default=2,
  92                         help="Number of significant digits after decimal point")
  93         self.OptionParser.add_option("-s", "--scale",
  94                         action="store", type="float",
  95                         dest="scale", default=1,
  96                         help="The distance above the curve")
  97         self.OptionParser.add_option("-r", "--orient",
  98                         action="store", type="inkbool",
  99                         dest="orient", default=True,
 100                         help="Keep orientation of text upright")
 101         self.OptionParser.add_option("--tab",
 102                         action="store", type="string",
 103                         dest="tab", default="sampling",
 104                         help="The selected UI-tab when OK was pressed")
 105         self.OptionParser.add_option("--measurehelp",
 106                         action="store", type="string",
 107                         dest="measurehelp", default="",
 108                         help="dummy")
 109
 110     def effect(self):
 111         # get number of digits
 112         prec = int(self.options.precision)
 113         # loop over all selected pathes
 114         for id, node in self.selected.iteritems():
 115             if node.tagName == 'path':
 116                 # self.group = self.document.createElement('svg:g')
 117                 self.group = self.document.createElement('svg:text')
 118                 node.parentNode.appendChild(self.group)
 119
 120                 try:
 121                     t = node.attributes.getNamedItem('transform').value
 122                     self.group.setAttribute('transform', t)
 123                 except AttributeError:
 124                     pass
 125
 126                 a =[]
 127                 p = cubicsuperpath.parsePath(node.attributes.getNamedItem('d').value)
 128                 num = 1
 129                 slengths, stotal = csplength(p)
 130                 ''' Wio: Umrechnung in unit '''
 131                 if self.options.unit=="mm":
 132                     factor=0.2822219  # px->mm
 133                 elif self.options.unit=="pt":
 134                     factor=0.80       # px->pt
 135                 elif self.options.unit=="cm":
 136                     factor=0.02822219 # px->cm
 137                 elif self.options.unit=="m":
 138                     factor=0.0002822219 # px->m
 139                 elif self.options.unit=="km":
 140                     factor=0.0000002822219 # px->km
 141                 elif self.options.unit=="in":
 142                     factor=0.2822219/25.4 # px->in
 143                 else :
 144                     ''' Default unit is px'''
 145                     factor=1
 146                     self.options.unit="px"
 147
 148                 # Format the length as string
 149                 lenstr = locale.format("%(len)25."+str(prec)+"f",{'len':round(stotal*factor*self.options.scale,prec)}).strip()
 150                 self.addTextOnPath(self.group,0, 0,lenstr+' '+self.options.unit, id, self.options.offset)
 151
 152
 153     def addTextOnPath(self,node,x,y,text, id,dy=0):
 154                 #new = self.document.createElement('svg:text')
 155                 new = self.document.createElement('svg:textPath')
 156                 s = {'text-align': 'center', 'vertical-align': 'bottom',
 157                     'text-anchor': 'middle', 'font-size': str(self.options.fontsize),
 158                     'fill-opacity': '1.0', 'stroke': 'none',
 159                     'font-weight': 'normal', 'font-style': 'normal', 'fill': '#000000'}
 160                 new.setAttribute('style', simplestyle.formatStyle(s))
 161                 node.setAttribute('x', str(x))
 162                 node.setAttribute('y', str(y))
 163                 #node.setAttribute('transform','rotate(180,'+str(-x)+','+str(-y)+')')
 164                 new.setAttributeNS('http://www.w3.org/1999/xlink','xlink:href', '#'+id)
 165                 new.setAttribute('startOffset', "50%")
 166                 new.setAttribute('dy', str(dy)) # dubious merit
 167                 #new.appendChild(tp)
 168                 new.appendChild(self.document.createTextNode(str(text)))
 169                 node.appendChild(new)
 170
 171 e = Length()
 172 e.affect()