Here are some PBRT renders I made, to compare between using photon mapping and using regular raybouncing. I recompiled PBRT with the advanced Photon Mapping Integrator (C++ code available here) to speed up the Final Gathering algorithm. There’s still a lot of noise in the final image, but the caustics are clearly visible.
I’ve also made a (failed) attempt at subsurface scattering, but it’s a nice render anyway:
If you want to experiment with Physically Based Rendering, PBRT is the tool to use. Unfortunately, the latest builds (>1.03) have some incomplete instructions on how to build PBRT on your own machine. I’ve built it on Ubuntu 9.10 and 10.04 using the following instructions:
- PBRT needs the OpenEXR libraries, but unlike it mentions in its makefile, just installing openexr and libopenexr-dev is not enough. The full apt-get install line should read:
sudo apt-get install openexr openexr-viewers libopenexr-dev libilmbase-dev.
- The makefile looks for EXR libraries in /usr/local/*, while ubuntu installs them in /usr/lib. The following lines in the makefile should be changed:
EXRINCLUDE = -I/usr/local/include/OpenEXR to EXRINCLUDE = -I/usr/include/OpenEXR
EXRLIBDIR = -L/usr/local/lib to EXRLIBDIR = -L/usr/lib
- PBRT should compile now, by running make in the source directory.
- Before you can render scenes, you should set the PBRT_SEARCHPATH environment variable. In a terminal, type:
export PBRT_SEARCHPATH = /location/to/pbrt/bin
(the bin folder was created in the make process)
Well, I hope this is a timesaver! :)
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