def test_slide(self):
"""Example to use with slide presentation."""
square = Polygon([
Point(0, 8),
Point(0, 0),
Point(8, 0),
Point(8, 8)])
triangle = Polygon([
Point(8, 10),
Point(4, 6),
Point(12, 6)])
self.assertTrue (triangle.convex())
self.assertTrue (square.convex())
p = convexIntersect(square, triangle)
q = convexIntersect(triangle, square)
self.assertEqual(p, q)
real = Polygon([
Point(8, 6),
Point(8, 8),
Point(6, 8),
Point(4, 6)
])
self.assertTrue (samePolygon(p, real))
self.assertTrue (samePolygon(real, p))
def test_defective(self):
"""
This test case detected defect in algorithm. Resolving
it explained how to choose whether to advance p or q
before an intersection had been discovered.
"""
p = Polygon([
Point(241, 243),
Point(353, 210),
Point(393, 245),
Point(375, 398),
Point(257, 303)
])
q = Polygon([
Point(108, 189),
Point(268, 116),
Point(456, 180),
Point(434, 226),
Point(125, 486)
])
self.assertTrue(p.convex())
self.assertTrue(q.convex())
i1 = convexIntersect(p, q)
i2 = convexIntersect(q, p)
self.assertTrue(samePolygon(i1, i2))
def test_noIntersection(self):
"""Detect no intersection."""
square = Polygon(
[Point(-8, -8),
Point(8, -8),
Point(8, 8),
Point(-8, 8)])
triangle = Polygon([Point(23, 0), Point(25, 0), Point(24, 1)])
self.assertTrue(triangle.convex())
self.assertTrue(square.convex())
p = convexIntersect(square, triangle)
q = convexIntersect(triangle, square)
self.assertEqual(p, q)
self.assertIsNone(p)
def drawEverything(self):
"""Draw at timed frequency."""
self.master.after(frameDelay, self.drawEverything)
self.canvas.delete(ALL)
self.drawPolygon(self.p1, 'blue', '')
self.drawPolygon(self.p2, 'black', '')
intersect = convexIntersect(self.p1, self.p2)
self.drawPolygon(intersect, '', 'red')
def test_enclosing(self):
"""Detect when polygon wholly contains another polygon."""
square = Polygon(
[Point(-8, -8),
Point(8, -8),
Point(8, 8),
Point(-8, 8)])
triangle = Polygon([Point(-3, 0), Point(3, 0), Point(0, 3)])
self.assertTrue(triangle.convex())
self.assertTrue(square.convex())
p = convexIntersect(square, triangle)
q = convexIntersect(triangle, square)
self.assertEqual(p, q)
real = Polygon([Point(-3, 0), Point(3, 0), Point(0, 3)])
self.assertTrue(samePolygon(p, real))
self.assertTrue(samePolygon(real, p))
def showFull(self, event):
"""Show Intersection or generate new polygons."""
if self.intersection is None:
self.intersection = convexIntersect(self.p1, self.p2)
self.drawPolygon(self.intersection, 'red')
else:
self.canvas.delete(ALL)
self.p1 = computeRandom(v1, v1, v2, v2)
self.p2 = computeRandom(v3, v3, v4, v4)
self.drawPolygons(None)
self.intersection = None
def test_intersectNoPointsInCommon(self):
square = Polygon(
[Point(-2, -2),
Point(2, -2),
Point(2, 2),
Point(-2, 2)])
triangle = Polygon([Point(-3, 0), Point(3, 0), Point(0, 3)])
self.assertTrue(triangle.convex())
self.assertTrue(square.convex())
p = convexIntersect(square, triangle)
q = convexIntersect(triangle, square)
self.assertTrue(samePolygon(p, q))
real = Polygon([
Point(2, 0),
Point(2, 1),
Point(1, 2),
Point(-1, 2),
Point(-2, 1),
Point(-2, 0)
])
self.assertTrue(samePolygon(p, real))
self.assertTrue(samePolygon(real, p))
def test_intersect(self):
# Note: only works if convex polygons in
# normal form, with points/edges in counter-clockwise
# fashion.
square = Polygon(
[Point(-2, -2),
Point(2, -2),
Point(2, 2),
Point(-2, 2)])
triangle = Polygon([Point(-2, -2), Point(2, -2), Point(0, 4)])
self.assertTrue(triangle.convex())
self.assertTrue(square.convex())
p = convexIntersect(square, triangle)
q = convexIntersect(triangle, square)
self.assertTrue(samePolygon(p, q))
real = Polygon(
[Point(2 / 3, 2),
Point(-2 / 3, 2),
Point(-2, -2),
Point(2, -2)])
self.assertTrue(samePolygon(p, real))
self.assertTrue(samePolygon(real, p))