#trace

Scene.Trace leaves SceneTraceResult.Hitbox null unless the trace calls .UseHitboxes(true). A target that carries model hitboxes but no body collider is invisible to a plain trace: the ray reports no hit at all. Mixing a coarse collider with hitboxes lets the collider shadow them, so a head shot resolves as a body hit.

A multi-hull vmdl authored with per-shape collision_tags does not get those tags at runtime -- a scene ModelCollider overwrites every shape with the GameObject's own tags, so Scene.Trace.WithoutTags can't filter one hull from another. Split the hulls across separate collider GameObjects instead.

SceneTraceResult.EndPosition on a sphere-radius sweep is the sphere's CENTRE at contact, not the contact point. Treating it as where the feet landed is off by a full radius. Derive the real contact position as from + (to - from) * Fraction in one helper. A related trap: snapping the sphere exactly tangent to the floor makes the next horizontal sweep intermittently report StartedSolid.

For a swept sphere/hull trace, HitPosition is the true surface contact point while EndPosition is the swept shape's centre at impact. Seat surface effects at HitPosition.

A zero-radius Scene.Trace.Ray passes straight through coarse voxel ModelColliders and returns Hit=false. Sweep a thin sphere (.Radius(...)) and it hits.