t, the distance along the ray to the hit, in the ray's units
The hit triangle's flat normal, in local space; zero for a shape without triangles
Ignored, and reported as zero, while triangleIndex is -1.
Hit point, in the node's local space
Index of the triangle hit, or -1 for a shape without triangles
Texture coordinate at the hit; zero for a shape without triangles
The buffer a hit test writes into, which an IHitVolume3D fills in on a hit
Everything in it is in the node's local space; events and View3D#raycast report the closest hit in world space, as a RaycastHit3D. One buffer is reused for every test, so a hit has to write every field.
Example