Friday, July 2, 2010

Brigade path tracer comparison

The following screenshots are taken from the Brigade real-time path tracer demo, available at http://igad.nhtv.nl/~bikker/
Rendered with CPU only at resolution 832x512
Images with 100 and 800 spp were taken without frame averaging (only 1 iteration)
Images with 2, 8, 16, 32 spp taken with frame averaging (averaging samples of several frames)

2 spp


8 spp


16 spp


32 spp


100 spp


800 spp



To top it off, one big image comparing 800, 8, 16 and 32 spp. It amazes me that the quality of just 8 samples is already great and with some filtering it could rival the quality of the 800 spp image:

2 comments:

sebh said...

I have tried the demo and it was really impressive!
Frame averaging however looks really ugly, especially with moving objects.

I wonderer if the authors are considering the use of reprojection cache: http://www.cs.princeton.edu/gfx/pubs/Nehab_2007_ARS/NehEtAl07.pdf . I thing that it could help.

Ray Tracey said...

Thanks for the paper, Seb. The reprojection technique could very well work here imo. But I think it's only good for diffuse materials (which is also a limit of the frame averaging technique)

Some time ago, I read a paper by Vlastimil Havran on exploiting interframe spatio-temporal coherency with bidirectional path tracing: http://www.mpi-inf.mpg.de/resources/anim/EGSR03/ . This might also work.