def test_simplification(self):
# Points are clockwise oriented
points = Vector2D.from_coordinates(
( 0.1, 10.1), # 0
( -0.1, 10.9), # 1
( 0.1, 20.1), # 2
( 0 , 30 ), # 3 *
( 15.1, 30.1), # 4
( 30 , 30 ), # 5 *
( 29.9, 10.0), # 6
( 30 , 0 ), # 7 *
( 15.1, 0.1), # 8
( 0 , 0 ), # 9 *
)
polygon = Polygon2D(*points)
simplified_polygon = polygon.simplify(threshold=1.)
simplified_polygon_truth = Polygon2D(*[points[i] for i in (3, 5, 7, 9)])
self.assertEqual(simplified_polygon, simplified_polygon_truth)
points = Vector2D.from_coordinates(
( 0 , 0 ),
( 0.1, 10.1),
( 0.2, 20.1),
)
polygon = Polygon2D(*points)
simplified_polygon = polygon.simplify(threshold=1.)
self.assertIsNone(simplified_polygon)
def test_convex_hull(self):
# 6 *
# 5 *
# 4 +
# 3 + + + *
# 2 * + *
# 1 * *
# 0 *
# - 0 1 2 3 4 5 6 7
# Points are clockwise oriented
points = Vector2D.from_coordinates(
(0, 0), # 0 p0
(-1, 2), # 1 *
(0, 3), # 2
(2, 4), # 3
(1, 5), # 4 *
(4, 6), # 5 *
(3, 3), # 6
(5, 3), # 7
(7, 3), # 8 *
(7, 2), # 9 *
(6, 1), # 10 *
(3, 2), # 11
(2, 1), # 12
)
convex_hull_points = [points[i] for i in (0, 10, 9, 8, 5, 4, 1)] # ccw
polygon = Polygon2D(*points)
convex_hull_truth = Polygon2D(*convex_hull_points)
self.assertTrue(polygon.is_simple)
self.assertFalse(polygon.is_convex)
self.assertTrue(polygon.is_concave)
self.assertTrue(polygon.is_clockwise)
self.assertFalse(polygon.is_counterclockwise)
convex_hull = polygon.convex_hull()
self.assertListEqual(list(convex_hull.points), convex_hull_points)
self.assertEqual(convex_hull, convex_hull_truth)
self.assertFalse(convex_hull.is_clockwise)
self.assertTrue(convex_hull.is_counterclockwise)
reversed_polygon = Polygon2D(*reversed(points))
self.assertFalse(reversed_polygon.is_clockwise)
self.assertTrue(reversed_polygon.is_counterclockwise)
convex_hull2 = reversed_polygon.convex_hull()
self.assertEqual(convex_hull, convex_hull2)
self.assertFalse(convex_hull2.is_clockwise)
self.assertTrue(convex_hull2.is_counterclockwise)
# Simplify
simplified_polygon = convex_hull.simplify(threshold=.1)
self.assertEqual(simplified_polygon, convex_hull_truth)
def _make_polygon(self):
points = Vector2D.from_coordinates(
(0, 0),
(-1, 2),
(0, 3),
(2, 4),
(1, 5),
(4, 6),
(3, 3),
(5, 3),
(7, 3),
(7, 2),
(6, 1),
(3, 2),
(2, 1),
)
polygon = Polygon2D(*points)
return polygon
