Source code for simvx.graphics.picking.raycast

"""CPU-side raycaster for entity intersection tests."""


from __future__ import annotations

import logging

import numpy as np

log = logging.getLogger(__name__)

__all__ = ["ray_aabb_intersect"]




def ray_aabb_intersect(
    origin: np.ndarray,
    direction: np.ndarray,
    aabb_min: np.ndarray,
    aabb_max: np.ndarray,
) -> tuple[bool, float]:
    """Test ray-AABB intersection. Returns (hit, t_near)."""
    inv_dir = 1.0 / np.where(direction != 0, direction, 1e-30)
    t1 = (aabb_min - origin) * inv_dir
    t2 = (aabb_max - origin) * inv_dir
    t_near = np.max(np.minimum(t1, t2))
    t_far = np.min(np.maximum(t1, t2))
    hit = (t_near <= t_far) and (t_far >= 0)
    return bool(hit), float(t_near)