[Radiance-general] Announcing the RADIANCE out-of-core photon map

[Schregle Roland HSLU T&A]

Dear RADIANCE community,

we are proud to announce the release of a heavily revised RADIANCE photon  
map which includes parallelisation and out-of-core storage. This is the  
final outcome of the software developed during our project at the  
Competence Centre Envelopes and Solar Energy at the Lucerne University of  
Applied Sciences and Arts.

The out-of-core photon map enables simulations with very large numbers of  
photons on commodity hardware using on-demand loading and caching  
techniques. This is particularly useful with annual simulations using  
rcontrib, where the number of required photons scales linearly with the  
number of timestamps.

Since we consider out-of-core storage an advanced option, it must be  
explicitly enabled during compilation of the RADIANCE software; currently  
the original in-core photon map is still the default. Details on building  
the out-of-core photon map from source are documented in the RADIANCE  
distribution under ray/doc/notes compile_switches. Irrespective of the  
storage option used, mkpmap is now parallelised and accepts the '-n'  
option.

The software is now available from the RADIANCE CVS repository and will be  
included in the next official release. We provide this software to the  
community as is, with the caveat that it is not actively supported; I can  
volunteer limited support in my free time when possible, particularly in  
response to reported bugs.

The out-of-core photon map is documented in a paper in the Journal of  
Building Performance Simulation, and in an online technical report:
http://www.tandfonline.com/doi/full/10.1080/19401493.2016.1177116
https://www.researchgate.net/publication/303550129_The_RADIANCE_Out-of-Core_Photon_Map_Technical_Report

This work was supported by the Swiss National Science Foundation as part  
of the project ‘Simulation-based assessment of daylight redirecting  
components for energy savings in office buildings’ under grant SNSF  
#147053.

Best regards and happy photon mapping,

  --Roland


-- 
Dr. Roland Schregle
Senior Research Associate

Lucerne University of Applied Sciences and Arts
School of Engineering and Architecture
CC Envelopes and Solar Energy (EASE)
www.hslu.ch/ccease