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#!/usr/bin/env python
'''
Copyright (C) 2005,2007,2008 Aaron Spike, aaron@ekips.org
Copyright (C) 2008 Alvin Penner, penner@vaxxine.com
- template dxf_outlines.dxf added Feb 2008 by Alvin Penner
- ROBO-Master output option added Aug 2008
- ROBO-Master multispline output added Sept 2008
- LWPOLYLINE output modification added Dec 2008
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
'''
import inkex, simplepath, simplestyle, cubicsuperpath, coloreffect, dxf_templates, math
import gettext
_ = gettext.gettext
try:
from numpy import *
from numpy.linalg import solve
except:
inkex.errormsg(_("Failed to import the numpy or numpy.linalg modules. These modules are required by this extension. Please install them and try again."))
inkex.sys.exit()
def pointdistance((x1,y1),(x2,y2)):
return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))
def get_fit(u, csp, col):
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]
def get_matrix(u, i, j):
if j == i + 2:
return (u[i]-u[i-1])*(u[i]-u[i-1])/(u[i+2]-u[i-1])/(u[i+1]-u[i-1])
elif j == i + 1:
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])
elif j == i:
return (u[i+1]-u[i])*(u[i+1]-u[i])/(u[i+1]-u[i-2])/(u[i+1]-u[i-1])
else:
return 0
class MyEffect(inkex.Effect):
def __init__(self):
inkex.Effect.__init__(self)
self.OptionParser.add_option("-R", "--ROBO", action="store", type="string", dest="ROBO")
self.dxf = []
self.handle = 255 # handle for DXF ENTITY
self.csp_old = [[0.0,0.0]]*4 # previous spline
self.d = array([0], float) # knot vector
self.poly = [[0.0,0.0]] # LWPOLYLINE data
def output(self):
print ''.join(self.dxf)
def dxf_add(self, str):
self.dxf.append(str)
def dxf_line(self,csp):
if (abs(csp[0][0] - self.poly[-1][0]) > .0001
or abs(csp[0][1] - self.poly[-1][1]) > .0001):
self.LWPOLY_output() # terminate current polyline
self.poly = [csp[0]] # initiallize new polyline
self.color_LWPOLY = self.color
self.poly.append(csp[1])
def LWPOLY_output(self):
if len(self.poly) == 1:
return
self.handle += 1
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)))
for i in range(len(self.poly)):
self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (self.poly[i][0],self.poly[i][1]))
def dxf_spline(self,csp):
knots = 8
ctrls = 4
self.handle += 1
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))
self.dxf_add(" 70\n8\n 71\n3\n 72\n%d\n 73\n%d\n 74\n0\n" % (knots, ctrls))
for i in range(2):
for j in range(4):
self.dxf_add(" 40\n%d\n" % i)
for i in csp:
self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (i[0],i[1]))
def ROBO_spline(self,csp):
# this spline has zero curvature at the endpoints, as in ROBO-Master
if (abs(csp[0][0] - self.csp_old[3][0]) > .0001
or abs(csp[0][1] - self.csp_old[3][1]) > .0001
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):
self.ROBO_output() # terminate current spline
self.xfit = array([csp[0][0]], float) # initiallize new spline
self.yfit = array([csp[0][1]], float)
self.d = array([0], float)
self.color_ROBO = self.color
self.xfit = concatenate((self.xfit, zeros((3)))) # append to current spline
self.yfit = concatenate((self.yfit, zeros((3))))
self.d = concatenate((self.d, zeros((3))))
for i in range(1, 4):
j = len(self.d) + i - 4
self.xfit[j] = get_fit(i/3.0, csp, 0)
self.yfit[j] = get_fit(i/3.0, csp, 1)
self.d[j] = self.d[j-1] + pointdistance((self.xfit[j-1],self.yfit[j-1]),(self.xfit[j],self.yfit[j]))
self.csp_old = csp
def ROBO_output(self):
if len(self.d) == 1:
return
fits = len(self.d)
ctrls = fits + 2
knots = ctrls + 4
self.xfit = concatenate((self.xfit, zeros((2)))) # pad with 2 endpoint constraints
self.yfit = concatenate((self.yfit, zeros((2)))) # pad with 2 endpoint constraints
self.d = concatenate((self.d, zeros((6)))) # pad with 3 duplicates at each end
self.d[fits+2] = self.d[fits+1] = self.d[fits] = self.d[fits-1]
solmatrix = zeros((ctrls,ctrls), dtype=float)
for i in range(fits):
solmatrix[i,i] = get_matrix(self.d, i, i)
solmatrix[i,i+1] = get_matrix(self.d, i, i+1)
solmatrix[i,i+2] = get_matrix(self.d, i, i+2)
solmatrix[fits, 0] = self.d[2]/self.d[fits-1] # curvature at start = 0
solmatrix[fits, 1] = -(self.d[1] + self.d[2])/self.d[fits-1]
solmatrix[fits, 2] = self.d[1]/self.d[fits-1]
solmatrix[fits+1, fits-1] = (self.d[fits-1] - self.d[fits-2])/self.d[fits-1] # curvature at end = 0
solmatrix[fits+1, fits] = (self.d[fits-3] + self.d[fits-2] - 2*self.d[fits-1])/self.d[fits-1]
solmatrix[fits+1, fits+1] = (self.d[fits-1] - self.d[fits-3])/self.d[fits-1]
xctrl = solve(solmatrix, self.xfit)
yctrl = solve(solmatrix, self.yfit)
self.handle += 1
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))
self.dxf_add(" 70\n0\n 71\n3\n 72\n%d\n 73\n%d\n 74\n%d\n" % (knots, ctrls, fits))
for i in range(knots):
self.dxf_add(" 40\n%f\n" % self.d[i-3])
for i in range(ctrls):
self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (xctrl[i],yctrl[i]))
for i in range(fits):
self.dxf_add(" 11\n%f\n 21\n%f\n 31\n0.0\n" % (self.xfit[i],self.yfit[i]))
def effect(self):
#References: Minimum Requirements for Creating a DXF File of a 3D Model By Paul Bourke
# NURB Curves: A Guide for the Uninitiated By Philip J. Schneider
# The NURBS Book By Les Piegl and Wayne Tiller (Springer, 1995)
self.dxf_add("999\nDXF created by Inkscape\n")
self.dxf_add(dxf_templates.r14_header)
scale = 25.4/90.0
h = inkex.unittouu(self.document.getroot().xpath('@height', namespaces=inkex.NSS)[0])
path = '//svg:path'
for node in self.document.getroot().xpath(path, namespaces=inkex.NSS):
style = node.get('style')
start = style.find("stroke:")
if style[start+11] == ';':
rgb = simplestyle.parseColor(style[(start+7):(start+11)])
elif style[start+14] == ';':
rgb = simplestyle.parseColor(style[(start+7):(start+14)])
else:
rgb = (0,0,0)
hsl = coloreffect.ColorEffect.rgb_to_hsl(coloreffect.ColorEffect(),rgb[0]/255.0,rgb[1]/255.0,rgb[2]/255.0)
self.color = 7 # default is black
if hsl[2]:
self.color = 1 + (int(6*hsl[0] + 0.5) % 6) # use 6 hues
d = node.get('d')
sim = simplepath.parsePath(d)
if len(sim):
simplepath.scalePath(sim,scale,-scale)
simplepath.translatePath(sim,0,h*scale)
p = cubicsuperpath.CubicSuperPath(sim)
for sub in p:
for i in range(len(sub)-1):
s = sub[i]
e = sub[i+1]
if s[1] == s[2] and e[0] == e[1]:
self.dxf_line([s[1],e[1]])
elif (self.options.ROBO == 'true'):
self.ROBO_spline([s[1],s[2],e[0],e[1]])
else:
self.dxf_spline([s[1],s[2],e[0],e[1]])
if self.options.ROBO == 'true':
self.ROBO_output()
self.LWPOLY_output()
self.dxf_add(dxf_templates.r14_footer)
if __name__ == '__main__':
e = MyEffect()
e.affect()
# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99
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