Feat: Add check_coplanar kwarg to Line.intersect_line (#320)

Co-authored-by: Andrew Hynes <andrewjhynes@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

src/skspatial/objects/line.py

@@ -475,7 +475,7 @@ def distance_line(self, other: Line) -> np.float64:
 
         return distance
 
-    def intersect_line(self, other: Line, **kwargs) -> Point:
+    def intersect_line(self, other: Line, check_coplanar: bool = True, **kwargs) -> Point:
         """
         Intersect the line with another.
 
@@ -485,6 +485,9 @@ def intersect_line(self, other: Line, **kwargs) -> Point:
         ----------
         other : Line
             Other line.
+        check_coplanar : bool, optional
+            Check that the lines are coplanar (default True).
+            If False, this method may not return an actual intersection point, but an approximate one.
         kwargs : dict, optional
             Additional keywords passed to :meth:`Vector.is_parallel`.
 
@@ -560,7 +563,7 @@ def intersect_line(self, other: Line, **kwargs) -> Point:
         if self.direction.is_parallel(other.direction, **kwargs):
             raise ValueError("The lines must not be parallel.")
 
-        if not self.is_coplanar(other):
+        if check_coplanar and not self.is_coplanar(other):
             raise ValueError("The lines must be coplanar.")
 
         # Vector from line A to line B.

src/skspatial/objects/line_segment.py

@@ -106,14 +106,17 @@ def contains_point(self, point: array_like, **kwargs) -> bool:
 
         return math.isclose(similarity, -1, **kwargs)
 
-    def intersect_line_segment(self, other: LineSegment) -> Point:
+    def intersect_line_segment(self, other: LineSegment, **kwargs) -> Point:
         """
         Intersect the line segment with another.
 
         Parameters
         ----------
         other : LineSegment
 
+        kwargs : dict, optional
+            Additional keyword arguments passed to :meth:`Line.intersect_line`.
+
         Returns
         -------
         Point
@@ -145,7 +148,7 @@ def intersect_line_segment(self, other: LineSegment) -> Point:
         line_a = Line.from_points(self.point_a, self.point_b)
         line_b = Line.from_points(other.point_a, other.point_b)
 
-        point_intersection = line_a.intersect_line(line_b)
+        point_intersection = line_a.intersect_line(line_b, **kwargs)
 
         point_on_segment_a = self.contains_point(point_intersection)
         point_on_segment_b = other.contains_point(point_intersection)

src/skspatial/objects/triangle.py

@@ -498,12 +498,17 @@ def altitude(self, vertex: str) -> Line:
 
         raise ValueError("The vertex must be 'A', 'B', or 'C'.")
 
-    def orthocenter(self) -> Point:
+    def orthocenter(self, **kwargs) -> Point:
         """
         Return the orthocenter of the triangle.
 
         The orthocenter is the intersection point of the three altitudes.
 
+        Parameters
+        ----------
+        kwargs : dict, optional
+            Additional keywords passed to :meth:`Line.intersect_line`.
+
         Returns
         -------
         Point
@@ -523,7 +528,7 @@ def orthocenter(self) -> Point:
         line_alt_a = self.altitude('A')
         line_alt_b = self.altitude('B')
 
-        return line_alt_a.intersect_line(line_alt_b)
+        return line_alt_a.intersect_line(line_alt_b, **kwargs)
 
     def classify(self, **kwargs: float) -> str:
         """

tests/unit/objects/test_line.py

@@ -213,18 +213,20 @@ def test_distance_line(line_a, line_b, dist_expected):
 
 
 @pytest.mark.parametrize(
-    ("line_a", "line_b", "array_expected"),
+    ("line_a", "line_b", "array_expected", "check_coplanar"),
     [
-        (Line([0, 0], [1, 0]), Line([0, 0], [1, 1]), [0, 0]),
-        (Line([0, 0], [1, 0]), Line([5, 5], [1, 1]), [0, 0]),
-        (Line([0, 0], [1, 0]), Line([9, 0], [1, 1]), [9, 0]),
-        (Line([0, 0], [1, 1]), Line([4, 0], [1, -1]), [2, 2]),
-        (Line([0, 0, 0], [1, 1, 1]), Line([4, 4, 0], [-1, -1, 1]), [2, 2, 2]),
+        (Line([0, 0], [1, 0]), Line([0, 0], [1, 1]), [0, 0], True),
+        (Line([0, 0], [1, 0]), Line([5, 5], [1, 1]), [0, 0], True),
+        (Line([0, 0], [1, 0]), Line([9, 0], [1, 1]), [9, 0], True),
+        (Line([0, 0], [1, 1]), Line([4, 0], [1, -1]), [2, 2], True),
+        (Line([0, 0, 0], [1, 1, 1]), Line([4, 4, 0], [-1, -1, 1]), [2, 2, 2], True),
+        (Line([0, 0, 0], [1, 1, 0]), Line([4, 5, 0], [-1, 0, 0]), [5, 5, 0], True),
+        (Line([0, 0, 0], [1, 1, 0]), Line([4, 5, 1], [-1, 0, 0]), [5, 5, 0], False),
     ],
 )
-def test_intersect_line(line_a, line_b, array_expected):
+def test_intersect_line(line_a, line_b, array_expected, check_coplanar):
 
-    point_intersection = line_a.intersect_line(line_b)
+    point_intersection = line_a.intersect_line(line_b, check_coplanar)
     assert point_intersection.is_close(array_expected)