#!/usr/bin/env python ''' Copyright (C) 2006 Georg Wiora, xorx@quarkbox.de Copyright (C) 2006 Johan Engelen, johan@shouraizou.nl Copyright (C) 2005 Aaron Spike, aaron@ekips.org 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 Changes: * This program is a modified version of wavy.py by Aaron Spike. * 22-Dec-2006: Wiora : Added axis and isotropic scaling ''' import inkex, simplepath, simplestyle from math import * from random import * def drawfunction(xstart, xend, ybottom, ytop, samples, width, height, left, bottom, fx = "sin(x)", fpx = "cos(x)", fponum = True, times2pi = False, isoscale = True, drawaxis = True): if times2pi == True: xstart = 2 * pi * xstart xend = 2 * pi * xend # coords and scales based on the source rect scalex = width / (xend - xstart) xoff = left coordx = lambda x: (x - xstart) * scalex + xoff #convert x-value to coordinate scaley = height / (ytop - ybottom) yoff = bottom coordy = lambda y: (ybottom - y) * scaley + yoff #convert y-value to coordinate # Check for isotropic scaling and use smaller of the two scales, correct ranges if isoscale: if scaley=0: # xaxis a.append(['M ',[left, coordy(0)]]) a.append([' l ',[width, 0]]) # check for visibility of y-axis if xstart<=0 and xend>=0: # xaxis a.append([' M ',[coordx(0),bottom]]) a.append([' l ',[0, -height]]) # initialize function and derivative for 0; # they are carried over from one iteration to the next, to avoid extra function calculations. y0 = f(xstart) if fponum == True: # numerical derivative, using 0.001*step as the small differential d0 = (f(xstart + 0.001*step) - y0)/(0.001*step) else: # derivative given by the user d0 = fp(xstart) # Start curve a.append([' M ',[coordx(xstart), coordy(y0)]]) # initial moveto for i in range(int(samples-1)): x = (i+1) * step + xstart y1 = f(x) if fponum == True: # numerical derivative d1 = (y1 - f(x - 0.001*step))/(0.001*step) else: # derivative given by the user d1 = fp(x) # create curve a.append([' C ',[coordx(x - step + third), coordy(y0 + (d0 * third)), coordx(x - third), coordy(y1 - (d1 * third)), coordx(x), coordy(y1)]]) y0 = y1 # next segment's y0 is this segment's y1 d0 = d1 # we assume the function is smooth everywhere, so carry over the derivative too return a class FuncPlot(inkex.Effect): def __init__(self): inkex.Effect.__init__(self) self.OptionParser.add_option("--xstart", action="store", type="float", dest="xstart", default=0.0, help="Start x-value") self.OptionParser.add_option("--xend", action="store", type="float", dest="xend", default=1.0, help="End x-value") self.OptionParser.add_option("--times2pi", action="store", type="inkbool", dest="times2pi", default=True, help="Multiply x-range by 2*pi") self.OptionParser.add_option("--ybottom", action="store", type="float", dest="ybottom", default=-1.0, help="y-value of rectangle's bottom") self.OptionParser.add_option("--ytop", action="store", type="float", dest="ytop", default=1.0, help="y-value of rectangle's top") self.OptionParser.add_option("-s", "--samples", action="store", type="int", dest="samples", default=8, help="Samples") self.OptionParser.add_option("--fofx", action="store", type="string", dest="fofx", default="sin(x)", help="f(x) for plotting") self.OptionParser.add_option("--fponum", action="store", type="inkbool", dest="fponum", default=True, help="Calculate the first derivative numerically") self.OptionParser.add_option("--fpofx", action="store", type="string", dest="fpofx", default="cos(x)", help="f'(x) for plotting") self.OptionParser.add_option("--remove", action="store", type="inkbool", dest="remove", default=True, help="If True, source rectangle is removed") self.OptionParser.add_option("--isoscale", action="store", type="inkbool", dest="isoscale", default=True, help="If True, isotropic scaling is used") self.OptionParser.add_option("--drawaxis", action="store", type="inkbool", dest="drawaxis", default=True, help="If True, axis are drawn") self.OptionParser.add_option("--tab", action="store", type="string", dest="tab", default="sampling", help="The selected UI-tab when OK was pressed") self.OptionParser.add_option("--pythonfunctions", action="store", type="string", dest="pythonfunctions", default="", help="dummy") def effect(self): for id, node in self.selected.iteritems(): if node.tag == inkex.addNS('rect','svg'): # create new path with basic dimensions of selected rectangle newpath = inkex.etree.Element(inkex.addNS('path','svg')) x = float(node.get('x')) y = float(node.get('y')) w = float(node.get('width')) h = float(node.get('height')) #copy attributes of rect s = node.get('style') newpath.set('style', s) try: t = node.get('transform') newpath.set('transform', t) except AttributeError: pass # top and bottom where exchanhged newpath.set('d', simplepath.formatPath( drawfunction(self.options.xstart, self.options.xend, self.options.ybottom, self.options.ytop, self.options.samples, w,h,x,y+h, self.options.fofx, self.options.fpofx, self.options.fponum, self.options.times2pi, self.options.isoscale, self.options.drawaxis))) newpath.set('title', self.options.fofx) #newpath.setAttribute('desc', '!func;' + self.options.fofx + ';' # + self.options.fpofx + ';' # + `self.options.fponum` + ';' # + `self.options.xstart` + ';' # + `self.options.xend` + ';' # + `self.options.samples`) # add path into SVG structure node.getparent().append(newpath) # option wether to remove the rectangle or not. if self.options.remove: node.getparent().remove(node) e = FuncPlot() e.affect()