Latest release include has some important updates for Windows users:
- Experimental multi-processing rcontrib: now rcontrib can be run with -n > 1. It’s a workaround for the lack of fork() on Windows. Do expect larger memory footprint. Stability on real world models untested.
- In general much better Windows ray tracing performance, should be on par with MacOS and Linux.
2 Likes
Great news! I will be testing it over the next few days. Thanks!!
This is super exciting @Taoning_Wang1! I’m trying to run rfluxmtx with n > 1 on Windows now, but it doesn’t seem to be working.
vwrays -vtv -vp -7.968 2.611 7.978 -vd 1 0 0 -vu 0 0 1 -vv 90 -vh 120 -x 600 -y 300 -pj 0.7 -c 9 -ff | rfluxmtx -n 8 -v -ffc -x 520 -y 300 -o glazing_1/g1%03d.hdr -ab 2 -ad 200 -lw 1e-2 -c 9 - glazing_1.rad -i scene.oct
rfluxmtx: running: rcontrib -fo+ -n 8 -o glazing_1/g1%03d.hdr -ab 2 -ad 200 -lw 1e-2 -x 520 -y 300 -ffc -c 9 -f klems_full.cal -p RHS=+1 -bn Nkbins -b kbin(1.22465e-16,1,-9.05942e-14,0,0,1) -m m000005 "!oconv -f -i scene.oct glazing_1.rad"
Only one thread is utilized. My Radiance version is RADIANCE 6.1a 2026-01-30 LBNL (6.1.74b430c613).
Sorry about that. Looks like I forgot to update one of the header files.
1 Like
I checked in the missing files from @Taoning_Wang and the latest HEAD containing the necessary changes is compiled here.
Best,
-Greg
1 Like
Hi @Taoning_Wang1,
There seems to be an issue when reading some sensor files when using n > 1 on Windows. Here is the rfluxmtx call and the error.
rfluxmtx -I -ab 2 -ad 512 -c 1 -faf -n 16 -y 221 - sky.dome -i scene.oct < grid.pts > results.dc
rcontrib: system - PeekNamedPipe() failed: No such file or directory
Do you know what the issue is? Let me know if you have any questions. If I set -n to 1 or just remove -n completely it runs without issues.
I am using the latest version: RADIANCE 6.1a 2026-02-22 LBNL (6.1.a69eae17fd).
Here is a downloadable sample. There is another sensor file in the ZIP, 884.pts, which is not causing any issues: Google Drive
Thanks, Mikkel. This is really helpful. The difference between your working input file and the non working input file is whether the input contains value “6.5”. It’s a weird Windows bug. I am working on a fix now.
1 Like
@Taoning_Wang1 just checked in a new build that should hopefully fix this issue. It is included in the lastest Radiance HEAD release.
-G
1 Like