/usr/share/doc/python-box2d-doc/examples/convex_hull.py is in python-box2d-doc 2.3.2~dfsg-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 | #!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# C++ version Copyright (c) 2006-2007 Erin Catto http://www.box2d.org
# Python version by Ken Lauer / sirkne at gmail dot com
#
# This software is provided 'as-is', without any express or implied
# warranty. In no event will the authors be held liable for any damages
# arising from the use of this software.
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
# 1. The origin of this software must not be misrepresented; you must not
# claim that you wrote the original software. If you use this software
# in a product, an acknowledgment in the product documentation would be
# appreciated but is not required.
# 2. Altered source versions must be plainly marked as such, and must not be
# misrepresented as being the original software.
# 3. This notice may not be removed or altered from any source distribution.
from .framework import (Framework, Keys, main)
from Box2D import (b2Clamp, b2Color, b2PolygonShape, b2Random,
b2_maxPolygonVertices)
class ConvexHull (Framework):
name = "ConvexHull"
description = ('Press g to generate a new random convex hull, a to switch '
'to automatic mode')
def __init__(self):
Framework.__init__(self)
self.auto = False
self.generate()
def generate(self):
lower = (-8, -8)
upper = (8, 8)
self.verts = verts = []
for i in range(b2_maxPolygonVertices):
x = 10.0 * b2Random(0.0, 10.0)
y = 10.0 * b2Random(0.0, 10.0)
# Clamp onto a square to help create collinearities.
# This will stress the convex hull algorithm.
verts.append(b2Clamp((x, y), lower, upper))
def Keyboard(self, key):
if key == Keys.K_a:
self.auto = not self.auto
elif key == Keys.K_g:
self.generate()
def Step(self, settings):
Framework.Step(self, settings)
renderer = self.renderer
try:
poly = b2PolygonShape(vertices=self.verts)
except AssertionError as ex:
self.Print('b2PolygonShape failed: %s' % ex)
else:
self.Print('Valid: %s' % poly.valid)
renderer.DrawPolygon([renderer.to_screen(v)
for v in self.verts], b2Color(0.9, 0.9, 0.9))
for i, v in enumerate(self.verts):
renderer.DrawPoint(renderer.to_screen(v), 2.0,
b2Color(0.9, 0.5, 0.5))
x, y = renderer.to_screen(v)
self.DrawStringAt(x + 0.05, y + 0.05, '%d' % i)
if self.auto:
self.generate()
if __name__ == "__main__":
main(ConvexHull)
|