fixes #1094 is_inside_polygon() function was incorrect

Replaced by the is_point_in_polygon_2d() function,
which even has a fast Cython implementation.

notes/pages/CHANGELOG.md

@@ -11,6 +11,8 @@
 		- {{issue 1082}}
 	- BUGFIX: add reactors to entities in `GROUP`
 		- {{issue 1085}}
+	- BUGFIX: `clipping.is_inside_polygon()` function was incorrect
+		- {{issue 1094}}
 		-
 - ## Version 1.3.0 - 2024-05-01
   id:: 65e30c28-021e-4c24-ab6e-a9e9fa7c6a51

src/ezdxf/math/clipping.py

@@ -683,30 +683,8 @@ def next_vertex_node(v: _Node) -> _Node:
 
 
 def is_inside_polygon(vertex: Vec2, polygon: GHPolygon) -> bool:
-    """Returns ``True`` if  `vertex` is inside `polygon` (odd-even rule).
-
-    This function calculates the "winding" number for a point, which
-    represents the number of times a ray emitted from the point to
-    infinity intersects any edge of the polygon.
-
-    An even winding number means the point lies OUTSIDE the polygon;
-    an odd number means it lies INSIDE it.
-    """
-    winding_number: int = 0
-    infinity = Vec2(polygon.max_x * 2, vertex.y)
-    for node in polygon:
-        if not node.intersect:
-            if (
-                line_intersection(
-                    vertex,
-                    infinity,
-                    node.vtx,
-                    next_vertex_node(node.next).vtx,
-                )[0]
-                is not None
-            ):
-                winding_number += 1
-    return bool(winding_number % 2)
+    """Returns ``True`` if  `vertex` is inside `polygon`."""
+    return is_point_in_polygon_2d(vertex, polygon.points, abs_tol=TOLERANCE) >= 0
 
 
 _ERROR = None, 0, 0

tests/test_06_math/test_619_greiner_hormann.py

@@ -2,7 +2,7 @@
 #  License: MIT License
 
 import pytest
-from ezdxf.math import Vec2
+from ezdxf.math import Vec2, BoundingBox2d
 from ezdxf.math.clipping import (
     greiner_hormann_union,
     greiner_hormann_difference,
@@ -21,6 +21,7 @@ class TestLineIntersection:
     polygons.
 
     """
+
     def test_start_point_is_not_an_intersection_point(self):
         s1, s2 = Vec2(1, 1), Vec2(3, 1)
         c1, c2 = Vec2(2, 1), Vec2(2, 2)
@@ -71,8 +72,8 @@ def test_parallel_horizontal_lines_do_not_intersect(self):
         assert line_intersection(s1, s2, c1, c2)[0] is None
 
     def test_collinear_lines_do_not_intersect(self):
-        s1, s2 = Vec2(0, 0), Vec2(4, 4)
-        c1, c2 = Vec2(2, 2), Vec2(4, 0)
+        s1, s2 = Vec2(0, 0), Vec2(2, 2)
+        c1, c2 = Vec2(3, 3), Vec2(4, 4)
         assert line_intersection(s1, s2, c1, c2)[0] is None
 
     @pytest.mark.parametrize(
@@ -162,8 +163,7 @@ def test_overlapping_polygons_are_united(self, rect, overlapping):
         assert set(UNION_OVERLAPPING) == set(result)
 
     def test_vertex_order_is_not_important(self, rect, overlapping):
-        """The vertex order (clockwise or counter clockwise) is not important.
-        """
+        """The vertex order (clockwise or counter clockwise) is not important."""
         rect.reverse()
         result = greiner_hormann_union(rect, overlapping)[0]
         assert set(UNION_OVERLAPPING) == set(result)
@@ -280,5 +280,97 @@ def test_polygon_outside_polygon(self, rect, outside):
         assert len(greiner_hormann_intersection(rect, outside)) == 0
 
 
+DATA_1094 = [
+    Vec2.list(
+        [
+            [-18.900001889999952, 1450.7000002308125],
+            [-18.900001889999952, 1470.7351470734998],
+            [1278.90012789, 1470.7351470734998],
+            [1278.90012789, 1450.70001562087],
+            [1503.6001841952093, 1450.7000156208703],
+            [1503.6001841952093, 1388.3850000081884],
+            [1503.6001841952093, 1388.3850000081884],
+            [1647.3246376764234, 1388.3850000081884],
+            [1647.3246376764234, 1548.1475422037274],
+            [1831.0471719722357, 1548.1475422037274],
+            [1831.0471719722357, 1388.3850000081884],
+            [1831.0471719722357, 1388.3850000081884],
+            [1980.6216566984945, 1388.3850000081884],
+            [1980.6216566984945, 1224.6149999918116],
+            [1831.0471719722357, 1224.6149999918116],
+            [1831.0471719722357, 1160.3525263520064],
+            [1647.3246376764234, 1160.3525263520064],
+            [1647.3246376764234, 1160.3525263520064],
+            [1647.3246376764234, 1224.6149999918116],
+            [1647.3246376764234, 1224.6149999918116],
+            [1503.6001841952093, 1224.6149999918116],
+            [1503.6001841952093, 1162.2999997691875],
+            [1278.90012789, 1162.2999997691877],
+            [1278.90012789, 1162.2999997691877],
+            [1278.90012789, 286.7000156208702],
+            [1503.6001841952093, 286.70001562087026],
+            [1503.6001841952093, 224.3850000081885],
+            [1503.6001841952093, 224.3850000081885],
+            [1647.3246376764234, 224.3850000081885],
+            [1647.3246376764234, 384.1475422037275],
+            [1831.0471719722357, 384.1475422037275],
+            [1831.0471719722357, 224.3850000081885],
+            [1831.0471719722357, 224.3850000081885],
+            [1980.6216566984945, 224.3850000081885],
+            [1980.6216566984945, 60.61499999181149],
+            [1831.0471719722357, 60.614999991811544],
+            [1831.0471719722357, -3.6474736479937064],
+            [1647.3246376764234, -3.6474736479937064],
+            [1647.3246376764234, -3.6474736479937064],
+            [1647.3246376764234, 60.61499999181149],
+            [1647.3246376764234, 60.61499999181149],
+            [1503.6001841952093, 60.61499999181149],
+            [1503.6001841952093, -1.7000002308124635],
+            [1278.90012789, -1.7000002308124635],
+            [1278.90012789, -1.7000002308124635],
+            [1278.90012789, -21.735002173499993],
+            [-18.900001890000045, -21.735002173499993],
+            [-18.900001890000045, -21.735002173499993],
+            [-18.900001890000045, -1.7000156208705448],
+            [-243.6001841952094, -1.7000156208702606],
+            [-243.6001841952094, -1.7000156208702606],
+            [-243.6001841952094, 60.61499999181149],
+            [-243.6001841952094, 60.61499999181149],
+            [-237.7502641782885, 60.61499999181149],
+            [-237.7502641782885, 224.3850000081885],
+            [-243.6001841952094, 224.3850000081885],
+            [-243.6001841952094, 286.70000023081246],
+            [-18.900001890000027, 286.7000002308125],
+            [-18.900001890000027, 286.7000002308125],
+            [-18.90000188999997, 1162.2999843791297],
+            [-243.6001841952094, 1162.2999843791297],
+            [-243.6001841952094, 1162.2999843791297],
+            [-243.6001841952094, 1450.7000002308125],
+            [-18.900001889999952, 1450.7000002308125],
+        ]
+    ),
+    Vec2.list(
+        [
+            [-392.2502641782885, 1224.6149999918116],
+            [-237.7502641782885, 1224.6149999918116],
+            [-237.7502641782885, 1388.3850000081884],
+            [-392.2502641782885, 1388.3850000081884],
+            [-392.2502641782885, 1224.6149999918116],
+        ]
+    ),
+]
+
+
+def test_issue_1094_is_inside_polygon_function_was_incorrect():
+    data = DATA_1094
+    box_expected = BoundingBox2d(data[0] + data[1])
+    result = greiner_hormann_union(data[0], data[1])
+
+    assert len(result) == 1
+    box_result = BoundingBox2d(result[0])
+    assert box_result.extmin.isclose(box_expected.extmin)
+    assert box_result.extmax.isclose(box_expected.extmax)
+
+
 if __name__ == "__main__":
     pytest.main([__file__])