[boolean] Add basic boolean functionality (boolean() and Polygon.boolean())

masque/test/test_boolean.py

@@ -0,0 +1,119 @@
+import pytest
+import numpy
+from numpy.testing import assert_allclose
+from masque.pattern import Pattern
+from masque.shapes.polygon import Polygon
+from masque.repetition import Grid
+from masque.library import Library
+
+def test_layer_as_polygons_basic() -> None:
+    pat = Pattern()
+    pat.polygon((1, 0), [[0, 0], [1, 0], [1, 1], [0, 1]])
+
+    polys = pat.layer_as_polygons((1, 0), flatten=False)
+    assert len(polys) == 1
+    assert isinstance(polys[0], Polygon)
+    assert_allclose(polys[0].vertices, [[0, 0], [1, 0], [1, 1], [0, 1]])
+
+def test_layer_as_polygons_repetition() -> None:
+    pat = Pattern()
+    rep = Grid(a_vector=(2, 0), a_count=2)
+    pat.polygon((1, 0), [[0, 0], [1, 0], [1, 1], [0, 1]], repetition=rep)
+
+    polys = pat.layer_as_polygons((1, 0), flatten=False)
+    assert len(polys) == 2
+    # First polygon at (0,0)
+    assert_allclose(polys[0].vertices, [[0, 0], [1, 0], [1, 1], [0, 1]])
+    # Second polygon at (2,0)
+    assert_allclose(polys[1].vertices, [[2, 0], [3, 0], [3, 1], [2, 1]])
+
+def test_layer_as_polygons_flatten() -> None:
+    lib = Library()
+
+    child = Pattern()
+    child.polygon((1, 0), [[0, 0], [1, 0], [1, 1]])
+    lib['child'] = child
+
+    parent = Pattern()
+    parent.ref('child', offset=(10, 10), rotation=numpy.pi/2)
+
+    polys = parent.layer_as_polygons((1, 0), flatten=True, library=lib)
+    assert len(polys) == 1
+    # Original child at (0,0) with rot pi/2 is still at (0,0) in its own space?
+    # No, ref.as_pattern(child) will apply the transform.
+    # Child (0,0), (1,0), (1,1) rotated pi/2 around (0,0) -> (0,0), (0,1), (-1,1)
+    # Then offset by (10,10) -> (10,10), (10,11), (9,11)
+
+    # Let's verify the vertices
+    expected = numpy.array([[10, 10], [10, 11], [9, 11]])
+    assert_allclose(polys[0].vertices, expected, atol=1e-10)
+
+def test_boolean_import_error() -> None:
+    from masque import boolean
+    # If pyclipper is not installed, this should raise ImportError
+    try:
+        import pyclipper  # noqa: F401
+        pytest.skip("pyclipper is installed, cannot test ImportError")
+    except ImportError:
+        with pytest.raises(ImportError, match="Boolean operations require 'pyclipper'"):
+            boolean([], [], operation='union')
+
+def test_polygon_boolean_shortcut() -> None:
+    poly = Polygon([[0, 0], [1, 0], [1, 1]])
+    # This should also raise ImportError if pyclipper is missing
+    try:
+        import pyclipper  # noqa: F401
+        pytest.skip("pyclipper is installed")
+    except ImportError:
+        with pytest.raises(ImportError, match="Boolean operations require 'pyclipper'"):
+            poly.boolean(poly)
+
+def test_bridge_holes() -> None:
+    from masque.utils.boolean import _bridge_holes
+
+    # Outer: 10x10 square
+    outer = numpy.array([[0, 0], [10, 0], [10, 10], [0, 10]])
+    # Hole: 2x2 square in the middle
+    hole = numpy.array([[4, 4], [6, 4], [6, 6], [4, 6]])
+
+    bridged = _bridge_holes(outer, [hole])
+
+    # We expect more vertices than outer + hole
+    # Original outer has 4, hole has 4. Bridge adds 2 (to hole) and 2 (back to outer) + 1 to close hole loop?
+    # Our implementation:
+    # 1. outer up to bridge edge (best_edge_idx)
+    # 2. bridge point on outer
+    # 3. hole reordered starting at max X
+    # 4. close hole loop (repeat max X)
+    # 5. bridge point on outer again
+    # 6. rest of outer
+
+    # max X of hole is 6 at (6,4) or (6,6). argmax will pick first one.
+    # hole vertices: [4,4], [6,4], [6,6], [4,6]. argmax(x) is index 1: (6,4)
+    # roll hole to start at (6,4): [6,4], [6,6], [4,6], [4,4]
+
+    # intersection of ray from (6,4) to right:
+    # edges of outer: (0,0)-(10,0), (10,0)-(10,10), (10,10)-(0,10), (0,10)-(0,0)
+    # edge (10,0)-(10,10) spans y=4.
+    # intersection at (10,4). best_edge_idx = 1 (edge from index 1 to 2)
+
+    # vertices added:
+    # outer[0:2]: (0,0), (10,0)
+    # bridge pt: (10,4)
+    # hole: (6,4), (6,6), (4,6), (4,4)
+    # hole close: (6,4)
+    # bridge pt back: (10,4)
+    # outer[2:]: (10,10), (0,10)
+
+    expected_len = 11
+    assert len(bridged) == expected_len
+
+    # verify it wraps around the hole and back
+    # index 2 is bridge_pt
+    assert_allclose(bridged[2], [10, 4])
+    # index 3 is hole reordered max X
+    assert_allclose(bridged[3], [6, 4])
+    # index 7 is hole closed at max X
+    assert_allclose(bridged[7], [6, 4])
+    # index 8 is bridge_pt back
+    assert_allclose(bridged[8], [10, 4])