Thx to Jaws @ B3D:
System and method of adjusting ray origins when shading vertices with rays
From nAo:
Pana?
Fredi
System and method of adjusting ray origins when shading vertices with rays
The present invention is related to rendering computer animated video and/or images generally, and to adjusting the origins of rays cast for object-edge positions. The present invention includes identifying a location of a vertex positioned on a perimeter of an object defined in the object scene by a plurality of vertices. The plurality of vertices include the vertex positioned on the perimeter of the object. A shading position that corresponds to, but is offset from, the vertex is then established. A shading value is then computed for the vertex by reference to the shading position. The shading value may be computed, for example, by casting a ray from the shading position.
From nAo:
That patent is from Larry Gritz.
Mr. Gritz is an ex Pixar who founded Ex Luna. ExLuna got acquired by NVIDIA a couple of years ago. NVIDIA also settled some patents litigation between Pixar and ExLuna.
IIRC Gritz also developed BMRT (Blue Moon Rendering Tool) the first renderman compliant interface ray tracer (it used some kind of global illumination algorithm too..) who was used as ray server when PRMAN didn't supported ray tracing.
Now he's working on GELATO. That patent is about ExLuna rendering technology, now owned by NVIDIA.
Pana?

Fredi