#!/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