def test_intersect_segments_multiple_intersections():
"""Tests that polygons having multiple intersections are ordered correctly."""
pts1 = (Point2D(0, 0), Point2D(5, 0), Point2D(5, 5), Point2D(0, 5))
pts2 = (Point2D(6, 4), Point2D(5, 4), Point2D(5, 3), Point2D(6, 3))
pts3 = (Point2D(5, 3), Point2D(6, 3), Point2D(6, 4), Point2D(5, 4))
pts4 = (Point2D(7, 4), Point2D(5, 4), Point2D(5, 3), Point2D(6, 3),
Point2D(6, 2), Point2D(5, 2), Point2D(5, 1), Point2D(7, 1))
pts5 = (Point2D(5, 3), Point2D(6, 3), Point2D(6, 2), Point2D(5, 2),
Point2D(5, 1), Point2D(7, 1), Point2D(7, 4), Point2D(5, 4))
poly1 = Polygon2D(pts1)
poly2 = Polygon2D(pts2)
poly3 = Polygon2D(pts3)
poly4 = Polygon2D(pts4)
poly5 = Polygon2D(pts5)
int_polys1 = Polygon2D.intersect_segments(poly1, poly2, 0.01)
int_polys2 = Polygon2D.intersect_segments(poly1, poly3, 0.01)
int_polys3 = Polygon2D.intersect_segments(poly1, poly4, 0.01)
int_polys4 = Polygon2D.intersect_segments(poly1, poly4, 0.01)
assert int_polys1[0].vertices == int_polys2[0].vertices == \
(Point2D(0, 0), Point2D(5, 0), Point2D(5, 3), Point2D(5, 4),
Point2D(5, 5), Point2D(0, 5))
assert int_polys3[0].vertices == int_polys4[0].vertices == \
(Point2D(0, 0), Point2D(5, 0), Point2D(5, 1), Point2D(5, 2),
Point2D(5, 3), Point2D(5, 4), Point2D(5, 5), Point2D(0, 5))
def test_intersect_segments_zero_tolerance():
"""Tests that the default tolerance of 0 does not update nearby polygons."""
pts0 = (Point2D(1, 0), Point2D(4, 0), Point2D(4, 1.99), Point2D(1, 1.99))
polygon0 = Polygon2D(pts0)
pts1 = (Point2D(0, 2), Point2D(3, 2), Point2D(3, 4), Point2D(0, 4))
polygon1 = Polygon2D(pts1)
polygon2, polygon3 = Polygon2D.intersect_segments(polygon0, polygon1, 0)
assert len(polygon2.segments) == 4 # No new points
assert all([polygon0.vertices[i] == polygon2.vertices[i] for i in range(len(polygon0.vertices))])
assert len(polygon3.segments) == 4 # No new points
assert all([polygon1.vertices[i] == polygon3.vertices[i] for i in range(len(polygon1.vertices))])
polygon2, polygon3 = Polygon2D.intersect_segments(polygon0, polygon1, 0.02)
assert len(polygon2.segments) == 5 # Intersection within tolerance
assert len(polygon3.segments) == 5 # Intersection within tolerance
def test_intersect_segments_with_colinear_edges():
"""Tests that the default tolerance of 0 updates polygons which share part of an edge segment."""
pts0 = (Point2D(1, 0), Point2D(4, 0), Point2D(4, 2), Point2D(1, 2))
polygon0 = Polygon2D(pts0)
pts1 = (Point2D(0, 2), Point2D(3, 2), Point2D(3, 4), Point2D(0, 4))
polygon1 = Polygon2D(pts1)
polygon0, polygon1 = Polygon2D.intersect_segments(polygon0, polygon1, 0)
# Extra vertex added to polygon0, as expected
assert len(polygon0.segments) == 5
assert polygon0.vertices[3] == Point2D(3, 2)
assert polygon0.segments[2].p2 == Point2D(3, 2)
assert polygon0.segments[3].p1 == Point2D(3, 2)
# Extra vertex added to polygon1, as expected
assert len(polygon1.segments) == 5
assert polygon1.vertices[1] == Point2D(1, 2)
assert polygon1.segments[0].p2 == Point2D(1, 2)
assert polygon1.segments[1].p1 == Point2D(1, 2)
def test_intersect_segments():
"""Tests that polygons within tolerance distance have vertices updated."""
tolerance = 0.02
pts0 = (Point2D(1, 0), Point2D(4, 0), Point2D(4, 1.99), Point2D(1, 1.99))
polygon0 = Polygon2D(pts0)
pts1 = (Point2D(0, 2), Point2D(3, 2), Point2D(3, 4), Point2D(0, 4))
polygon1 = Polygon2D(pts1)
polygon0, polygon1 = Polygon2D.intersect_segments(polygon0, polygon1, tolerance)
# Extra vertex added to polygon0, as expected
assert len(polygon0.segments) == 5
assert polygon0.vertices[3] == Point2D(3, 1.99)
assert polygon0.segments[2].p2 == Point2D(3, 1.99)
assert polygon0.segments[3].p1 == Point2D(3, 1.99)
# Extra vertex added to polygon1, as expected
assert len(polygon1.segments) == 5
assert polygon1.vertices[1] == Point2D(1, 2)
assert polygon1.segments[0].p2 == Point2D(1, 2)
assert polygon1.segments[1].p1 == Point2D(1, 2)
