generate_voronoi.py revision d9b1d836390f0891fb0d18f7894a385cd1b38020
#!/usr/bin/env python
"""
Copyright (C) 2010 Alvin Penner, penner@vaxxine.com
- Voronoi Diagram algorithm and C code by Steven Fortune, 1987, http://ect.bell-labs.com/who/sjf/
- Python translation to file voronoi.py by Bill Simons, 2005, http://www.oxfish.com/
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 random, inkex, simplestyle, gettext, voronoi
_ = gettext.gettext
try:
from subprocess import Popen, PIPE
except:
inkex.errormsg(_("Failed to import the subprocess module. Please report this as a bug at : https://bugs.launchpad.net/inkscape."))
inkex.errormsg("Python version is : " + str(inkex.sys.version_info))
exit()
def clip_line(x1, y1, x2, y2, w, h):
if x1 < 0 and x2 < 0:
return [0, 0, 0, 0]
if x1 > w and x2 > w:
return [0, 0, 0, 0]
if x1 < 0:
y1 = (y1*x2 - y2*x1)/(x2 - x1)
x1 = 0
if x2 < 0:
y2 = (y1*x2 - y2*x1)/(x2 - x1)
x2 = 0
if x1 > w:
y1 = y1 + (w - x1)*(y2 - y1)/(x2 - x1)
x1 = w
if x2 > w:
y2 = y1 + (w - x1)*(y2 - y1)/(x2 - x1)
x2 = w
if y1 < 0 and y2 < 0:
return [0, 0, 0, 0]
if y1 > h and y2 > h:
return [0, 0, 0, 0]
if x1 == x2 and y1 == y2:
return [0, 0, 0, 0]
if y1 < 0:
x1 = (x1*y2 - x2*y1)/(y2 - y1)
y1 = 0
if y2 < 0:
x2 = (x1*y2 - x2*y1)/(y2 - y1)
y2 = 0
if y1 > h:
x1 = x1 + (h - y1)*(x2 - x1)/(y2 - y1)
y1 = h
if y2 > h:
x2 = x1 + (h - y1)*(x2 - x1)/(y2 - y1)
y2 = h
return [x1, y1, x2, y2]
class Pattern(inkex.Effect):
def __init__(self):
inkex.Effect.__init__(self)
self.OptionParser.add_option("--size",
action="store", type="int",
dest="size", default=10,
help="Average size of cell (px)")
self.OptionParser.add_option("--border",
action="store", type="int",
dest="border", default=0,
help="Size of Border (px)")
def effect(self):
if not self.options.ids:
inkex.errormsg(_("Please select an object"))
exit()
q = {'x':0,'y':0,'width':0,'height':0} # query the bounding box of ids[0]
for query in q.keys():
p = Popen('inkscape --query-%s --query-id=%s "%s"' % (query, self.options.ids[0], self.args[-1]), shell=True, stdout=PIPE, stderr=PIPE)
rc = p.wait()
q[query] = float(p.stdout.read())
defs = self.xpathSingle('/svg:svg//svg:defs')
pattern = inkex.etree.SubElement(defs ,inkex.addNS('pattern','svg'))
pattern.set('id', 'Voronoi' + str(random.randint(1, 9999)))
pattern.set('width', str(q['width']))
pattern.set('height', str(q['height']))
pattern.set('patternTransform', 'translate(%s,%s)' % (q['x'], q['y']))
pattern.set('patternUnits', 'userSpaceOnUse')
# generate random pattern of points
c = voronoi.Context()
pts = []
b = float(self.options.border) # width of border
for i in range(int(q['width']*q['height']/self.options.size/self.options.size)):
x = random.random()*q['width']
y = random.random()*q['height']
if b > 0: # duplicate border area
pts.append(voronoi.Site(x, y))
if x < b:
pts.append(voronoi.Site(x + q['width'], y))
if y < b:
pts.append(voronoi.Site(x + q['width'], y + q['height']))
if y > q['height'] - b:
pts.append(voronoi.Site(x + q['width'], y - q['height']))
if x > q['width'] - b:
pts.append(voronoi.Site(x - q['width'], y))
if y < b:
pts.append(voronoi.Site(x - q['width'], y + q['height']))
if y > q['height'] - b:
pts.append(voronoi.Site(x - q['width'], y - q['height']))
if y < b:
pts.append(voronoi.Site(x, y + q['height']))
if y > q['height'] - b:
pts.append(voronoi.Site(x, y - q['height']))
elif x > -b and y > -b and x < q['width'] + b and y < q['height'] + b:
pts.append(voronoi.Site(x, y)) # leave border area blank
# dot = inkex.etree.SubElement(pattern, inkex.addNS('rect','svg'))
# dot.set('x', str(x-1))
# dot.set('y', str(y-1))
# dot.set('width', '2')
# dot.set('height', '2')
if len(pts) < 3:
inkex.errormsg("Please choose a larger object, or smaller cell size")
exit()
# plot Voronoi diagram
sl = voronoi.SiteList(pts)
voronoi.voronoi(sl, c)
for edge in c.edges:
if edge[1] >= 0 and edge[2] >= 0: # two vertices
[x1, y1, x2, y2] = clip_line(c.vertices[edge[1]][0], c.vertices[edge[1]][1], c.vertices[edge[2]][0], c.vertices[edge[2]][1], q['width'], q['height'])
elif edge[1] >= 0: # only one vertex
if c.lines[edge[0]][1] == 0: # vertical line
xtemp = c.lines[edge[0]][2]/c.lines[edge[0]][0]
if c.vertices[edge[1]][1] > q['height']/2:
ytemp = q['height']
else:
ytemp = 0
else:
xtemp = q['width']
ytemp = (c.lines[edge[0]][2] - q['width']*c.lines[edge[0]][0])/c.lines[edge[0]][1]
[x1, y1, x2, y2] = clip_line(c.vertices[edge[1]][0], c.vertices[edge[1]][1], xtemp, ytemp, q['width'], q['height'])
elif edge[2] >= 0: # only one vertex
if c.lines[edge[0]][1] == 0: # vertical line
xtemp = c.lines[edge[0]][2]/c.lines[edge[0]][0]
if c.vertices[edge[2]][1] > q['height']/2:
ytemp = q['height']
else:
ytemp = 0
else:
xtemp = 0
ytemp = c.lines[edge[0]][2]/c.lines[edge[0]][1]
[x1, y1, x2, y2] = clip_line(xtemp, ytemp, c.vertices[edge[2]][0], c.vertices[edge[2]][1], q['width'], q['height'])
if x1 or x2 or y1 or y2:
path = 'M %f,%f %f,%f' % (x1, y1, x2, y2)
attribs = {'d': path, 'style': 'stroke:#000000'}
inkex.etree.SubElement(pattern, inkex.addNS('path', 'svg'), attribs)
# link selected object to pattern
obj = self.selected[self.options.ids[0]]
style = {}
if obj.attrib.has_key('style'):
style = simplestyle.parseStyle(obj.attrib['style'])
style['fill'] = 'url(#%s)' % pattern.get('id')
obj.attrib['style'] = simplestyle.formatStyle(style)
if obj.tag == inkex.addNS('g', 'svg'):
for node in obj:
style = {}
if node.attrib.has_key('style'):
style = simplestyle.parseStyle(node.attrib['style'])
style['fill'] = 'url(#%s)' % pattern.get('id')
node.attrib['style'] = simplestyle.formatStyle(style)
if __name__ == '__main__':
e = Pattern()
e.affect()
# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99