raygeo.geo.algo.intersect

Geometry intersection utilities.

Low-level intersection primitives for ray-segment and segment-segment tests, plus higher-level self-intersection and cross-intersection checks on geometry command arrays.

Functions

get_ray_line_intersection()

get_ray_line_intersection(
    origin: tuple[float, float],
    direction: tuple[float, float],
    a: tuple[float, float],
    b: tuple[float, float],
) -> tuple[float, float] | None

Intersect a ray with a line segment.

Given a ray starting at origin in the given direction, and a line segment from a to b, returns the intersection point if the ray hits the segment (including endpoints) in the forward direction, or None if there is no intersection.

Parameter	Type	Description
origin	tuple[float, float]	Ray start point (x, y).
direction	tuple[float, float]	Ray direction vector (dx, dy).
a	tuple[float, float]	Line segment start point (x, y).
b	tuple[float, float]	Line segment end point (x, y).
Returns	tuple[float, float] | None	Intersection point (x, y), or None.
Complexity		O(1) time, O(1) space

Ray–line segment intersection: the ray from origin O hits segments S₁ and S₂ (marked), misses S₃

get_ray_polygon_intersection()

get_ray_polygon_intersection(
    origin: tuple[float, float],
    direction: tuple[float, float],
    polygon: list[tuple[float, float]],
) -> tuple[float, float] | None

Intersect a ray with a polygon boundary.

Given a ray starting at origin in the given direction, and a closed polygon defined by a list of vertices, returns the closest intersection point with any edge of the polygon (including edge endpoints), or None if the ray does not hit the polygon in the forward direction.

Parameter	Type	Description
origin	tuple[float, float]	Ray start point (x, y).
direction	tuple[float, float]	Ray direction vector (dx, dy).
polygon	list[tuple[float, float]]	List of polygon vertices [(x1, y1), (x2, y2), ...].
Returns	tuple[float, float] | None	Closest intersection point (x, y), or None.
Complexity		O(N) time, O(1) space

Ray–polygon intersection: the ray from origin O hits the polygon boundary at the closest intersection point along the ray direction.