ray_cast()

std::optional< HitResult > MayaFlux::Kinesis::ray_cast ( const SpatialIndex3D &  index, const Ray &  ray, float  tolerance  )

inline

Find the closest entity to a ray within a tolerance radius.

Parameters

index	Published SpatialIndex3D to query.
ray	World-space ray (from screen_to_ray or constructed manually).
tolerance	Maximum perpendicular distance from the ray axis for a hit.

Returns

Closest entity within tolerance, or std::nullopt if nothing was hit.

Iterates all entities in the published snapshot. Entities behind the ray origin (t < 0) are rejected. Among forward candidates within tolerance, returns the one with the smallest perpendicular distance. Ties broken by smaller t (closer to camera).

Definition at line 115 of file HitTest.hpp.

{
    float tol_sq = tolerance * tolerance;
    std::optional<HitResult> best;
 
    for (const auto& [id, pos] : index.all()) {
        float t = 0.0F;
        float d_sq = point_ray_distance_sq(ray, pos, &t);
 
        if (t < 0.0F || d_sq > tol_sq) {
            continue;
        }
 
        float d = std::sqrt(d_sq);
 
        if (!best || d < best->distance || (d == best->distance && t < best->t)) {
            best = HitResult { .id = id, .distance = d, .t = t };
        }
    }
 
    return best;
}

References MayaFlux::Kinesis::SpatialIndex< PointT >::all(), distance(), MayaFlux::Kinesis::HitResult::id, id, and point_ray_distance_sq().

Here is the call graph for this function: