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|
# Copyright (c) 2024, Manfred Moitzi
# License: MIT License
# pylint: disable=redefined-outer-name # pytest-fixtures!
from __future__ import annotations
import pytest
from ezdxf.math import Vec2
from ezdxf.math.clipping import ConcaveClippingPolygon2d as CCP
# 0123456
# 8 .......
# 7 .7---6.
# 6 .|...|.
# 5 .|.4-5.
# 4 .|.|...
# 3 .|.3-2.
# 2 .|...|.
# 1 .0---1.
# 0 .......
# 0123456
SHAPE_C = Vec2.list(
# 0 1 2 3 4 5 6 7
[(1, 1), (5, 1), (5, 3), (3, 3), (3, 5), (5, 5), (5, 7), (1, 7)]
)
# 0123456
# 8 .......
# 7 .+---+.
# 6 .|678|.
# 5 .|5+-+.
# 4 .|4|...
# 3 .|3+-+.
# 2 .|012|.
# 1 .+---+.
# 0 .......
# 0123456
POINTS_INSIDE = Vec2.list(
# 0 1 2 3 4 5 6 7 8
[(2, 2), (3, 2), (4, 2), (2, 3), (2, 4), (2, 5), (2, 6), (3, 6), (4, 6)]
)
# 0123456
# 8 b.c.d.e
# 7 .+---+.
# 6 9|...|a
# 5 .|.+-+.
# 4 6|.|7.8
# 3 .|.+-+.
# 2 4|...|5
# 1 .+---+.
# 0 0.1.2.3
# 0123456
POINTS_OUTSIDE = Vec2.list(
[
(0, 0), # 0
(2, 0), # 1
(4, 0), # 2
(6, 0), # 3
(0, 2), # 4
(6, 2), # 5
(0, 4), # 6
(4, 4), # 7
(6, 2), # 8
(0, 6), # 9
(6, 6), # a
(0, 8), # b
(2, 8), # c
(4, 8), # d
(6, 8), # e
]
)
@pytest.fixture(scope="module")
def polygon_c():
return CCP(SHAPE_C)
# see also test_613_is_point_in_polygon_2d
@pytest.mark.parametrize("point", POINTS_INSIDE)
def test_point_is_inside_polygon(point: Vec2, polygon_c: CCP):
assert polygon_c.is_inside(point) is True
# see also test_613_is_point_in_polygon_2d
@pytest.mark.parametrize("point", POINTS_OUTSIDE)
def test_point_is_outside_polygon(point: Vec2, polygon_c: CCP):
assert polygon_c.is_inside(point) is False
class TestLineClipping:
def test_a_and_b_outside_no_intersections_v(self, polygon_c: CCP):
# 8 b......
# 7 .+---+.
# 6 .|...|.
# 5 .|.+-+.
# 4 .|.|...
# 3 .|.+-+.
# 2 .|...|.
# 1 .+---+.
# 0 a......
# 0123456
result = polygon_c.clip_line(Vec2(0, 0), Vec2(0, 8))
assert len(result) == 0
def test_a_and_b_outside_no_intersections_h(self, polygon_c: CCP):
# 3 .|.+-+.
# 2 .|...|.
# 1 .+---+.
# 0 a.....b
# 0123456
result = polygon_c.clip_line(Vec2(0, 0), Vec2(6, 0))
assert len(result) == 0
def test_a_and_b_inside_no_intersections_h(self, polygon_c: CCP):
# 3 .|.+-+.
# 2 .|a.b|.
# 1 .+---+.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(2, 2), Vec2(4, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((2, 2))
assert e.isclose((4, 2))
def test_a_outside_b_inside_1_intersection_v(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 .|b..|.
# 1 .+x--+.
# 0 ..a....
# 0123456
result = polygon_c.clip_line(Vec2(2, 0), Vec2(2, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((2, 1))
assert e.isclose((2, 2))
def test_a_outside_b_inside_1_intersection_h(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 axb..|.
# 1 .+---+.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(0, 2), Vec2(2, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((1, 2))
assert e.isclose((2, 2))
def test_a_inside_b_outside_1_intersection_v(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 .|a..|.
# 1 .+x--+.
# 0 ..b....
# 0123456
result = polygon_c.clip_line(Vec2(2, 2), Vec2(2, 0))
assert len(result) == 1
s, e = result[0]
assert s.isclose((2, 2))
assert e.isclose((2, 1))
def test_a_inside_b_outside_1_intersection_h(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 bxa..|.
# 1 .+---+.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(2, 2), Vec2(0, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((2, 2))
assert e.isclose((1, 2))
def test_a_outside_b_outside_2_intersections(self, polygon_c: CCP):
# 6 .|...|.
# 5 .|.+-+.
# 4 .|.|b..
# 3 .|.+x+.
# 2 .|...|.
# 1 .+--x+.
# 0 ....a..
# 0123456
result = polygon_c.clip_line(Vec2(4, 0), Vec2(4, 4))
assert len(result) == 1
s, e = result[0]
assert s.isclose((4, 1))
assert e.isclose((4, 3))
def test_a_outside_b_inside_3_intersections(self, polygon_c: CCP):
# 8 .......
# 7 .+---+.
# 6 .|..b|.
# 5 .|.+x+.
# 4 .|.|...
# 3 .|.+x+.
# 2 .|...|.
# 1 .+--x+.
# 0 ....a..
# 0123456
result = polygon_c.clip_line(Vec2(4, 0), Vec2(4, 6))
assert len(result) == 2
s0, e0 = result[0]
assert s0.isclose((4, 1))
assert e0.isclose((4, 3))
s1, e1 = result[1]
assert s1.isclose((4, 5))
assert e1.isclose((4, 6))
def test_a_inside_b_outside_3_intersections(self, polygon_c: CCP):
# 8 ....b..
# 7 .+--x+.
# 6 .|...|.
# 5 .|.+x+.
# 4 .|.|...
# 3 .|.+x+.
# 2 .|..a|.
# 1 .+---+.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(4, 2), Vec2(4, 8))
assert len(result) == 2
s0, e0 = result[0]
assert s0.isclose((4, 2))
assert e0.isclose((4, 3))
s1, e1 = result[1]
assert s1.isclose((4, 5))
assert e1.isclose((4, 7))
def test_line_intersection_at_vertex_outside_inside(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 .|b..|.
# 1 .x---+.
# 0 a......
# 0123456
result = polygon_c.clip_line(Vec2(0, 0), Vec2(2, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((1, 1))
assert e.isclose((2, 2))
def test_line_touches_vertex_outside_outside(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.3-2.
# 2 a|...|.
# 1 .x---1.
# 0 ..b....
# 0123456
result = polygon_c.clip_line(Vec2(0, 2), Vec2(2, 0))
assert len(result) == 0
def test_line_touches_vertex_inside_inside(self, polygon_c: CCP):
# 4 .|a|...
# 3 .|.3-2.
# 2 .|..b|.
# 1 .x---1.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(2, 4), Vec2(4, 2))
assert len(result) == 1
s, e = result[0]
assert s.isclose((2, 4))
assert e.isclose((4, 2))
def test_line_is_colinear_to_outer_edge(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.3-2.
# 2 .|...|.
# 1 ax+++xb
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(0, 1), Vec2(6, 1))
assert len(result) == 1
s, e = result[0]
assert s.isclose((1, 1))
assert e.isclose((5, 1))
def test_line_is_colinear_to_inner_edge(self, polygon_c: CCP):
"""Colinear line segments are inside per definition."""
# 4 .|.|...
# 3 ax+x+xb
# 2 .|...|.
# 1 .0---1.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(0, 3), Vec2(6, 3))
assert len(result) == 2
s, e = result[0]
assert s.isclose((1, 3))
assert e.isclose((3, 3))
s, e = result[1]
assert s.isclose((3, 3))
assert e.isclose((5, 3))
def test_line_is_colinear_to_inner_edge_reverse(self, polygon_c: CCP):
"""Colinear line segments are inside per definition."""
# 4 .|.|...
# 3 bx+x+xa
# 2 .|...|.
# 1 .0---1.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(6, 3), Vec2(0, 3))
assert len(result) == 2
s, e = result[0]
assert s.isclose((5, 3))
assert e.isclose((3, 3))
s, e = result[1]
assert s.isclose((3, 3))
assert e.isclose((1, 3))
def test_line_is_equal_to_edge(self, polygon_c: CCP):
# 4 .|.|...
# 3 .|.+-+.
# 2 .|...|.
# 1 .a---b.
# 0 .......
# 0123456
result = polygon_c.clip_line(Vec2(1, 1), Vec2(5, 1))
assert len(result) == 1
s, e = result[0]
assert s.isclose((1, 1))
assert e.isclose((5, 1))
# 11111
# 012345678901234
# 10 ...............
# 9 .7---6...3---2.
# 8 .|...|...|...|.
# 7 .|...|...|...|.
# 6 .|...|...|...|.
# 5 .|...5---4...|.
# 4 .|...........|.
# 3 .|...........|.
# 2 .|...........|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
SHAPE_U = Vec2.list(
# 0 1 2 3 4 5 6 7
[(1, 1), (13, 1), (13, 9), (9, 9), (9, 5), (5, 5), (5, 9), (1, 9)]
)
@pytest.fixture(scope="module")
def polygon_u():
return CCP(SHAPE_U)
class TestPolylineClipping:
def test_polyline_outside(self, polygon_u: CCP):
result = polygon_u.clip_polyline(
Vec2.list([(0, 0), (14, 0), (14, 10), (0, 10)])
)
assert len(result) == 0
def test_polyline_inside_no_intersection(self, polygon_u: CCP):
# 6 .|...|...|...|.
# 5 .|...5---4...|.
# 4 .|d+++++++++c|.
# 3 .|..........+|.
# 2 .|a+++++++++b|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polyline(Vec2.list([(2, 2), (12, 2), (12, 4), (2, 4)]))
assert len(result) == 1
polyline = result[0]
assert len(polyline) == 4
assert polyline[0].isclose((2, 2))
assert polyline[2].isclose((12, 4))
def test_polyline_inside_with_intersection(self, polygon_u: CCP):
# 7 .|...|...|...|.
# 6 .|d++x...x++c|.
# 5 .|...5---4..+|.
# 4 .|..........+|.
# 3 .|..........+|.
# 2 .|a+++++++++b|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polyline(Vec2.list([(2, 2), (12, 2), (12, 6), (2, 6)]))
assert len(result) == 2
p1, p2 = result
assert p1[0].isclose((2, 2))
assert p1[1].isclose((12, 2))
assert p1[2].isclose((12, 6))
assert p1[3].isclose((9, 6))
assert p2[0].isclose((5, 6))
assert p2[1].isclose((2, 6))
def test_polyline_crossing_border(self, polygon_u: CCP):
# 7 .|...|...|...|.
# 6 .|d++x...x++c|.
# 5 .|...5---4..+|.
# 4 .|..........+|.
# 3 .|..........+|.
# 2 .|..........+|.
# 1 .0----------x1.
# 0 ..a+++++++++b..
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polyline(Vec2.list([(2, 0), (12, 0), (12, 6), (2, 6)]))
assert len(result) == 2
p1, p2 = result
assert p1[0].isclose((12, 1))
assert p1[1].isclose((12, 6))
assert p1[2].isclose((9, 6))
assert p2[0].isclose((5, 6))
assert p2[1].isclose((2, 6))
def test_polyline_along_the_border_1(self, polygon_u: CCP):
# 10 ...............
# 9 .d+++x...x+++c.
# 8 .|...|...|...+.
# 7 .|...|...|...+.
# 6 .|...|...|...+.
# 5 .|...5---4...+.
# 4 .|...........+.
# 3 .|...........+.
# 2 .|...........+.
# 1 .a+++++++++++b.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polyline(Vec2.list([(1, 1), (13, 1), (13, 9), (1, 9)]))
assert len(result) == 2
p1, p2 = result
assert p1[0].isclose((1, 1))
assert p1[1].isclose((13, 1))
assert p1[2].isclose((13, 9))
assert p1[3].isclose((9, 9))
assert p2[0].isclose((5, 9))
assert p2[1].isclose((1, 9))
def test_polyline_along_the_border_2(self, polygon_u: CCP):
# 6 .|...|...|...|.
# 5 .d+++x+++x+++c.
# 4 .|...........+.
# 3 .|...........+.
# 2 .|...........+.
# 1 .a+++++++++++b.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polyline(Vec2.list([(1, 1), (13, 1), (13, 5), (1, 5)]))
assert len(result) == 1
p1 = result[0]
assert p1[0].isclose((1, 1))
assert p1[1].isclose((13, 1))
assert p1[2].isclose((13, 5))
assert p1[3].isclose((9, 5))
assert p1[4].isclose((5, 5))
assert p1[5].isclose((1, 5))
class TestPolygonClipping:
"""Based on the paper "Efficient Clipping of Arbitrary Polygons" by
Günther Greiner and Kai Hormann.
Tests see test_619_greiner_hormann.py
"""
@pytest.mark.parametrize(
"vertices",
[
[],
[Vec2()],
[Vec2(), Vec2()],
[Vec2(), Vec2(), Vec2()],
],
ids=["#0", "#1", "#2", "#3"],
)
def test_too_few_vertices(self, vertices, polygon_u: CCP):
assert len(polygon_u.clip_polygon(vertices)) == 0
def test_polygon_inside_no_intersection(self, polygon_u: CCP):
# 6 .|...|...|...|.
# 5 .|...5---4...|.
# 4 .|d+++++++++c|.
# 3 .|+.........+|.
# 2 .|a+++++++++b|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polygon(Vec2.list([(2, 2), (12, 2), (12, 4), (2, 4)]))
# returns the subject polygon [a, b, c, d]
assert len(result) == 1
polygon = result[0]
assert len(polygon) == 4
assert polygon[0].isclose((2, 2))
assert polygon[2].isclose((12, 4))
@pytest.mark.xfail(reason="edge case not covered")
def test_polygon_outside_no_intersection(self, polygon_u: CCP):
# 10 d.............c
# 9 .7---6...3---2.
# 8 .|...|...|...|.
# 7 .|...|...|...|.
# 6 .|...|...|...|.
# 5 .|...5---4...|.
# 4 .|...........|.
# 3 .|...........|.
# 2 .|...........|.
# 1 .0-----------1.
# 0 a.............b
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polygon(Vec2.list([(0, 0), (14, 0), (14, 10), (0, 10)]))
# returns the clipping polygon [0, 1, 2, 3, 4, 5, 6, 7]
assert len(result) == 1
polygon = result[0]
assert len(polygon) == 8
assert polygon[0] == Vec2(1, 1)
assert polygon[7] == Vec2(1, 9)
def test_polygon_inside_with_intersection(self, polygon_u: CCP):
# 7 .|d++x...x++c|.
# 6 .|+..+...+..+|.
# 5 .|+..5+++4..+|.
# 4 .|+.........+|.
# 3 .|+.........+|.
# 2 .|a+++++++++b|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polygon(Vec2.list([(2, 2), (12, 2), (12, 7), (2, 7)]))
assert len(result) == 1
polygon = result[0]
assert len(polygon) == 9
# returns a closed polygon!
assert polygon[0].isclose(polygon[-1]) is True
def test_polygon_colinear_edges(self, polygon_u: CCP):
# 5 .d+++5+++4++c|.
# 4 .+..........+|.
# 3 .+..........+|.
# 2 .a++++++++++b|.
# 1 .0-----------1.
# 0 ...............
# 11111
# 012345678901234
# a b c d
result = polygon_u.clip_polygon(Vec2.list([(1, 2), (12, 2), (12, 5), (1, 5)]))
# The Greiner-Hormann algorithm has issues with intersection points on polygon
# edges.
assert len(result) == 1
polygon = result[0]
# intersection points (4) and (5) are missing!
assert len(polygon) == 4
# returns an open polygon!
assert polygon[0].isclose(polygon[-1]) is False
if __name__ == "__main__":
pytest.main([__file__])
|
