Source code for simvx.graphics.picking.raycast_utils

"""Multi-ray casting helpers for batch intersection tests."""


from __future__ import annotations

import logging

import numpy as np

from .raycast import ray_aabb_intersect

log = logging.getLogger(__name__)

__all__ = ["compute_aabb", "cast_rays_single_hit", "cast_rays_multi_hit"]




def compute_aabb(
    center: np.ndarray,
    half_extents: np.ndarray,
) -> tuple[np.ndarray, np.ndarray]:
    """Compute world-space AABB from center position and half-extents."""
    return center - half_extents, center + half_extents





def cast_rays_single_hit(
    ray_origins: np.ndarray,
    ray_direction: np.ndarray,
    cubes: list[dict],
) -> np.ndarray:
    """Cast rays against cubes, return first hit cube index per ray.

    Returns (N,) array of hit cube indices, -1 for miss.
    """
    num_rays = len(ray_origins)
    hits = np.full(num_rays, -1, dtype=np.int32)

    for i in range(num_rays):
        origin = ray_origins[i]
        closest_t = float("inf")

        for cube in cubes:
            is_hit, t = ray_aabb_intersect(
                origin,
                ray_direction,
                cube["aabb_min"],
                cube["aabb_max"],
            )
            if is_hit and 0 <= t < closest_t:
                closest_t = t
                hits[i] = cube["index"]

    return hits





def cast_rays_multi_hit(
    ray_origins: np.ndarray,
    ray_direction: np.ndarray,
    cubes: list[dict],
) -> list[list[int]]:
    """Cast rays against cubes, return ALL hit cube indices per ray."""
    num_rays = len(ray_origins)
    hits: list[list[int]] = [[] for _ in range(num_rays)]

    for i in range(num_rays):
        origin = ray_origins[i]
        for cube in cubes:
            is_hit, t = ray_aabb_intersect(
                origin,
                ray_direction,
                cube["aabb_min"],
                cube["aabb_max"],
            )
            if is_hit and t >= 0:
                hits[i].append(cube["index"])

    return hits