Renamed effect and made an extended "Function Plotter". Kind of an excuse to showcase the 'notebook' parameter type i added.

(bzr r1707)

1 files changed, 163 insertions, 0 deletions

diff --git a/share/extensions/funcplot.py b/share/extensions/funcplot.py
new file mode 100644
index 000000000..f555bb612
--- /dev/null
+++ b/share/extensions/funcplot.py
@@ -0,0 +1,163 @@
+#!/usr/bin/env python 

+'''

+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

+

+This program is a modified version of wavy.py by Aaron Spike.

+

+'''

+import inkex, simplepath, simplestyle

+from math import *

+from random import *

+

+def drawfunction(xstart, xend, ybottom, ytop, samples, width, height, left, top, 

+    fx = "sin(x)", fpx = "cos(x)", fponum = True):

+

+    # step is the distance between nodes on x

+    step = (xend - xstart) / (samples-1)

+    third = step / 3.0

+    

+    # 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 = top

+    coordy = lambda y: (ytop-y) * scaley + yoff  #convert y-value to coordinate

+

+    # functions specified by the user

+    if fx != "":

+        f = eval('lambda x: ' + fx)

+    if fpx != "":

+        fp = eval('lambda x: ' + fpx)

+

+    # 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)

+

+    a = [] # path array 

+    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("--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("--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.tagName == 'rect':

+                # create new path with basic dimensions of selected rectangle

+                newpath = self.document.createElement('svg:path')

+                x = float(node.attributes.getNamedItem('x').value)

+                y = float(node.attributes.getNamedItem('y').value)

+                w = float(node.attributes.getNamedItem('width').value)

+                h = float(node.attributes.getNamedItem('height').value)

+

+                #copy attributes of rect

+                s = node.attributes.getNamedItem('style').value

+                newpath.setAttribute('style', s)

+                try:

+                    t = node.attributes.getNamedItem('transform').value

+                    newpath.setAttribute('transform', t)

+                except AttributeError:

+                    pass

+                    

+                newpath.setAttribute('d', simplepath.formatPath(

+                            drawfunction(self.options.xstart,

+                                self.options.xend,

+                                self.options.ybottom,

+                                self.options.ytop,

+                                self.options.samples, 

+                                w,h,x,y,

+                                self.options.fofx, 

+                                self.options.fpofx,

+                                self.options.fponum)))

+                newpath.setAttribute('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.parentNode.appendChild(newpath)

+                # TODO: make an option wether to remove the rectangle or not.

+                node.parentNode.removeChild(node)

+                

+e = FuncPlot()

+e.affect()
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