105 lines
3.5 KiB
Python
Executable file
105 lines
3.5 KiB
Python
Executable file
#!/usr/bin/env python3
|
|
# coding=utf-8
|
|
#
|
|
# Copyright (C) 2005 Carsten Goetze c.goetze@tu-bs.de
|
|
#
|
|
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
#
|
|
import math
|
|
import random
|
|
import inkex
|
|
from inkex.paths import Move, Line
|
|
|
|
|
|
def calculate_subdivision(smoothness, x1, y1, x2, y2):
|
|
# Calculate the vector from (x1,y1) to (x2,y2)
|
|
x3 = x2 - x1
|
|
y3 = y2 - y1
|
|
# Calculate the point half-way between the two points
|
|
hx = x1 + x3 / 2
|
|
hy = y1 + y3 / 2
|
|
# Calculate normalized vector perpendicular to the vector (x3,y3)
|
|
length = math.sqrt(x3 * x3 + y3 * y3)
|
|
if length != 0:
|
|
nx = -y3 / length
|
|
ny = x3 / length
|
|
else:
|
|
nx = 1
|
|
ny = 0
|
|
# Scale perpendicular vector by random factor """
|
|
r = random.uniform(-length / (1 + smoothness), length / (1 + smoothness))
|
|
nx = nx * r
|
|
ny = ny * r
|
|
# add scaled perpendicular vector to the half-way point to get the final displaced subdivision point
|
|
x = hx + nx
|
|
y = hy + ny
|
|
return (x, y)
|
|
|
|
|
|
class Fractalize(inkex.EffectExtension):
|
|
def add_arguments(self, pars):
|
|
pars.add_argument(
|
|
"-s", "--subdivs", type=int, default=6, help="Number of subdivisons"
|
|
)
|
|
pars.add_argument(
|
|
"-f",
|
|
"--smooth",
|
|
type=float,
|
|
default=4.0,
|
|
help="Smoothness of the subdivision",
|
|
)
|
|
|
|
def effect(self):
|
|
for node in self.svg.selection.filter(inkex.PathElement):
|
|
path = node.path.to_absolute()
|
|
result = []
|
|
for cmd_proxy in path.proxy_iterator(): # type: inkex.Path.PathCommandProxy
|
|
prev = cmd_proxy.previous_end_point
|
|
end = cmd_proxy.end_point
|
|
if cmd_proxy.letter == "M":
|
|
result.append(Move(*cmd_proxy.args))
|
|
else:
|
|
for seg in self.fractalize(
|
|
(prev.x, prev.y, end.x, end.y),
|
|
self.options.subdivs,
|
|
self.options.smooth,
|
|
):
|
|
result.append(Line(*seg))
|
|
result.append(Line(end.x, end.y))
|
|
|
|
node.path = result
|
|
|
|
def fractalize(self, coords, subdivs, smooth):
|
|
"""recursively subdivide the segments left and right of the subdivision"""
|
|
subdiv_point = calculate_subdivision(smooth, *coords)
|
|
|
|
if subdivs:
|
|
# recursively subdivide the segment left of the subdivision point
|
|
for left_seg in self.fractalize(
|
|
coords[:2] + subdiv_point[-2:], subdivs - 1, smooth
|
|
):
|
|
yield left_seg
|
|
|
|
yield subdiv_point
|
|
|
|
# recursively subdivide the segment right of the subdivision point
|
|
for right_seg in self.fractalize(
|
|
subdiv_point[-2:] + coords[-2:], subdivs - 1, smooth
|
|
):
|
|
yield right_seg
|
|
|
|
|
|
if __name__ == "__main__":
|
|
Fractalize().run()
|