share/extensions/dxf_outlines.py

   1 #!/usr/bin/env python
   2 '''
   3 Copyright (C) 2005,2007,2008 Aaron Spike, aaron@ekips.org
   4 Copyright (C) 2008 Alvin Penner, penner@vaxxine.com
   5
   6 - template dxf_outlines.dxf added Feb 2008 by Alvin Penner
   7 - ROBO-Master output option added Aug 2008
   8 - ROBO-Master multispline output added Sept 2008
   9 - LWPOLYLINE output modification added Dec 2008
  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 import inkex, simplepath, simplestyle, cubicsuperpath, coloreffect, dxf_templates, math
  26 import gettext
  27 _ = gettext.gettext
  28
  29 try:
  30     from numpy import *
  31     from numpy.linalg import solve
  32 except:
  33     inkex.errormsg(_("Failed to import the numpy or numpy.linalg modules. These modules are required by this extension. Please install them and try again."))
  34     inkex.sys.exit()
  35
  36 def pointdistance((x1,y1),(x2,y2)):
  37     return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))
  38
  39 def get_fit(u, csp, col):
  40     return (1-u)**3*csp[0][col] + 3*(1-u)**2*u*csp[1][col] + 3*(1-u)*u**2*csp[2][col] + u**3*csp[3][col]
  41
  42 def get_matrix(u, i, j):
  43     if j == i + 2:
  44         return (u[i]-u[i-1])*(u[i]-u[i-1])/(u[i+2]-u[i-1])/(u[i+1]-u[i-1])
  45     elif j == i + 1:
  46         return ((u[i]-u[i-1])*(u[i+2]-u[i])/(u[i+2]-u[i-1]) + (u[i+1]-u[i])*(u[i]-u[i-2])/(u[i+1]-u[i-2]))/(u[i+1]-u[i-1])
  47     elif j == i:
  48         return (u[i+1]-u[i])*(u[i+1]-u[i])/(u[i+1]-u[i-2])/(u[i+1]-u[i-1])
  49     else:
  50         return 0
  51
  52 class MyEffect(inkex.Effect):
  53     def __init__(self):
  54         inkex.Effect.__init__(self)
  55         self.OptionParser.add_option("-R", "--ROBO", action="store", type="string", dest="ROBO")
  56         self.OptionParser.add_option("--tab", action="store", type="string", dest="tab")
  57         self.OptionParser.add_option("--inputhelp", action="store", type="string", dest="inputhelp")
  58         self.dxf = []
  59         self.handle = 255                       # handle for DXF ENTITY
  60         self.csp_old = [[0.0,0.0]]*4            # previous spline
  61         self.d = array([0], float)              # knot vector
  62         self.poly = [[0.0,0.0]]                 # LWPOLYLINE data
  63     def output(self):
  64         print ''.join(self.dxf)
  65     def dxf_add(self, str):
  66         self.dxf.append(str)
  67     def dxf_line(self,csp):
  68         if (abs(csp[0][0] - self.poly[-1][0]) > .0001
  69             or abs(csp[0][1] - self.poly[-1][1]) > .0001):
  70             self.LWPOLY_output()                            # terminate current polyline
  71             self.poly = [csp[0]]                            # initiallize new polyline
  72             self.color_LWPOLY = self.color
  73         self.poly.append(csp[1])
  74     def LWPOLY_output(self):
  75         if len(self.poly) == 1:
  76             return
  77         self.handle += 1
  78         self.dxf_add("  0\nLWPOLYLINE\n  5\n%x\n100\nAcDbEntity\n  8\n0\n 62\n%d\n100\nAcDbPolyline\n 90\n%d\n 70\n0\n" % (self.handle, self.color_LWPOLY, len(self.poly)))
  79         for i in range(len(self.poly)):
  80             self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (self.poly[i][0],self.poly[i][1]))
  81     def dxf_spline(self,csp):
  82         knots = 8
  83         ctrls = 4
  84         self.handle += 1
  85         self.dxf_add("  0\nSPLINE\n  5\n%x\n100\nAcDbEntity\n  8\n0\n 62\n%d\n100\nAcDbSpline\n" % (self.handle, self.color))
  86         self.dxf_add(" 70\n8\n 71\n3\n 72\n%d\n 73\n%d\n 74\n0\n" % (knots, ctrls))
  87         for i in range(2):
  88             for j in range(4):
  89                 self.dxf_add(" 40\n%d\n" % i)
  90         for i in csp:
  91             self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (i[0],i[1]))
  92     def ROBO_spline(self,csp):
  93         # this spline has zero curvature at the endpoints, as in ROBO-Master
  94         if (abs(csp[0][0] - self.csp_old[3][0]) > .0001
  95             or abs(csp[0][1] - self.csp_old[3][1]) > .0001
  96             or abs((csp[1][1]-csp[0][1])*(self.csp_old[3][0]-self.csp_old[2][0]) - (csp[1][0]-csp[0][0])*(self.csp_old[3][1]-self.csp_old[2][1])) > .001):
  97             self.ROBO_output()                              # terminate current spline
  98             self.xfit = array([csp[0][0]], float)           # initiallize new spline
  99             self.yfit = array([csp[0][1]], float)
 100             self.d = array([0], float)
 101             self.color_ROBO = self.color
 102         self.xfit = concatenate((self.xfit, zeros((3))))    # append to current spline
 103         self.yfit = concatenate((self.yfit, zeros((3))))
 104         self.d = concatenate((self.d, zeros((3))))
 105         for i in range(1, 4):
 106             j = len(self.d) + i - 4
 107             self.xfit[j] = get_fit(i/3.0, csp, 0)
 108             self.yfit[j] = get_fit(i/3.0, csp, 1)
 109             self.d[j] = self.d[j-1] + pointdistance((self.xfit[j-1],self.yfit[j-1]),(self.xfit[j],self.yfit[j]))
 110         self.csp_old = csp
 111     def ROBO_output(self):
 112         if len(self.d) == 1:
 113             return
 114         fits = len(self.d)
 115         ctrls = fits + 2
 116         knots = ctrls + 4
 117         self.xfit = concatenate((self.xfit, zeros((2))))    # pad with 2 endpoint constraints
 118         self.yfit = concatenate((self.yfit, zeros((2))))    # pad with 2 endpoint constraints
 119         self.d = concatenate((self.d, zeros((6))))          # pad with 3 duplicates at each end
 120         self.d[fits+2] = self.d[fits+1] = self.d[fits] = self.d[fits-1]
 121         solmatrix = zeros((ctrls,ctrls), dtype=float)
 122         for i in range(fits):
 123             solmatrix[i,i]   = get_matrix(self.d, i, i)
 124             solmatrix[i,i+1] = get_matrix(self.d, i, i+1)
 125             solmatrix[i,i+2] = get_matrix(self.d, i, i+2)
 126         solmatrix[fits, 0]   = self.d[2]/self.d[fits-1]     # curvature at start = 0
 127         solmatrix[fits, 1]   = -(self.d[1] + self.d[2])/self.d[fits-1]
 128         solmatrix[fits, 2]   = self.d[1]/self.d[fits-1]
 129         solmatrix[fits+1, fits-1] = (self.d[fits-1] - self.d[fits-2])/self.d[fits-1]   # curvature at end = 0
 130         solmatrix[fits+1, fits]   = (self.d[fits-3] + self.d[fits-2] - 2*self.d[fits-1])/self.d[fits-1]
 131         solmatrix[fits+1, fits+1] = (self.d[fits-1] - self.d[fits-3])/self.d[fits-1]
 132         xctrl = solve(solmatrix, self.xfit)
 133         yctrl = solve(solmatrix, self.yfit)
 134         self.handle += 1
 135         self.dxf_add("  0\nSPLINE\n  5\n%x\n100\nAcDbEntity\n  8\n0\n 62\n%d\n100\nAcDbSpline\n" % (self.handle, self.color_ROBO))
 136         self.dxf_add(" 70\n0\n 71\n3\n 72\n%d\n 73\n%d\n 74\n%d\n" % (knots, ctrls, fits))
 137         for i in range(knots):
 138             self.dxf_add(" 40\n%f\n" % self.d[i-3])
 139         for i in range(ctrls):
 140             self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (xctrl[i],yctrl[i]))
 141         for i in range(fits):
 142             self.dxf_add(" 11\n%f\n 21\n%f\n 31\n0.0\n" % (self.xfit[i],self.yfit[i]))
 143
 144     def effect(self):
 145         #References:   Minimum Requirements for Creating a DXF File of a 3D Model By Paul Bourke
 146         #              NURB Curves: A Guide for the Uninitiated By Philip J. Schneider
 147         #              The NURBS Book By Les Piegl and Wayne Tiller (Springer, 1995)
 148         self.dxf_add("999\nDXF created by Inkscape\n")
 149         self.dxf_add(dxf_templates.r14_header)
 150
 151         scale = 25.4/90.0
 152         h = inkex.unittouu(self.document.getroot().xpath('@height', namespaces=inkex.NSS)[0])
 153         path = '//svg:path'
 154         for node in self.document.getroot().xpath(path, namespaces=inkex.NSS):
 155             rgb = (0,0,0)
 156             style = node.get('style')
 157             if style:
 158                 style = simplestyle.parseStyle(style)
 159                 if style.has_key('stroke'):
 160                     if style['stroke'] and style['stroke'] != 'none':
 161                         rgb = simplestyle.parseColor(style['stroke'])
 162             hsl = coloreffect.ColorEffect.rgb_to_hsl(coloreffect.ColorEffect(),rgb[0]/255.0,rgb[1]/255.0,rgb[2]/255.0)
 163             self.color = 7                                  # default is black
 164             if hsl[2]:
 165                 self.color = 1 + (int(6*hsl[0] + 0.5) % 6)  # use 6 hues
 166             d = node.get('d')
 167             sim = simplepath.parsePath(d)
 168             if len(sim):
 169                 simplepath.scalePath(sim,scale,-scale)
 170                 simplepath.translatePath(sim,0,h*scale)
 171                 p = cubicsuperpath.CubicSuperPath(sim)
 172                 for sub in p:
 173                     for i in range(len(sub)-1):
 174                         s = sub[i]
 175                         e = sub[i+1]
 176                         if s[1] == s[2] and e[0] == e[1]:
 177                             self.dxf_line([s[1],e[1]])
 178                         elif (self.options.ROBO == 'true'):
 179                             self.ROBO_spline([s[1],s[2],e[0],e[1]])
 180                         else:
 181                             self.dxf_spline([s[1],s[2],e[0],e[1]])
 182         if self.options.ROBO == 'true':
 183             self.ROBO_output()
 184         self.LWPOLY_output()
 185         self.dxf_add(dxf_templates.r14_footer)
 186
 187 if __name__ == '__main__':
 188     e = MyEffect()
 189     e.affect()
 190
 191
 192 # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99