They are using some sort of graph of connected volumes without hierarchy as their acceleration structure. This could be an interesting alternative to using a tree or grid.

I wish they:

1. Showed a visualisation of their data structure.

2. Gave a straight-up comparison against an alternative like Optix on the same hardware.

3. Characterised the possible construction algorithms to some extent, especially with respect to animated scenes.

It is just a poster, so it will be interesting to read the paper when it arrives.

There is code for this project available: http://sourceforge.net/projects/rayforce/?source=directory

They also have a gallery: http://clipboard.com/clip/LQKWhz7pKtAy_1cmySKwsOkeDLqT733mMj...