Radiance?

[AJLynn]

I got a question about Radiance today. Apparently it's available as a tarball that can compile on MacOSX. As far as I can tell, it's got a decent GI engine, but it's also got a learning curve and it's not free for commercial use.

 

Is anybody using it, or has anybody used it recently? I'm wondering whether there's any reason for us to use it (we're an architecture firm that's very interested in green design) considering that we already have Max9 and I've put the time into learning mental ray. For example, is Radiance the best tool for lighting simulation and design?

[John Dollus]

VisArc has been using Radiance for quite some time.

http://www.visarc.com/visarc/visarcadv/fs_vadv_1.htm

http://www.iesd.dmu.ac.uk/~jm/2006_Radiance_Workshop/Presentations/JackdeValpine.pdf

 

I looked at it years ago and remember it had a great tool for adjusting the final rendering to mimic the way the human eye interprets the environment. I am not sure how that relates to Logarithmic exposure but it was superior to most color mapping techniques.

 

There's a good book by Greg Larson you might want to pick up called 'Rendering with Radiance'. I have it and it's a good read that explains a lot of concepts useful if you are interested in global illumination and radiosity concepts.

[AJLynn]

Thanks. After more discussion, what they want is lighting analysis. It's the kind of thing I can use Max for, but apparently the LEED credit calls for Radiance... so I might end up using that... though it would certainly be easier if I could recycle my mental ray stuff with pseudocolor turned on.

[stefkeB]

Radiance = lighting simulation

3ds max = visualization (with some simulation tools included)

 

Do not mix the two. You can do 'nice' renderings in Radiance, but will have artifacts, extremely long rendering times and little support for animation. Use it for what it is meant to do: simulation.

 

There was an old conversion program for Windows that converted 3ds files (including texture coordinates) to Radiance scenes: ConRAD from http://www.openentry.dk It has disappeared, but I still have different versions of the software. But beware, it is not a simple process and you have to understand Radiance to be able to use it.

 

Radiance is available for Linux and OSX. There is/was a Windows version: Desktop Radiance, which integrated into AutoCAD (up to release 2000). It has been discontinued.

The current Radiance version can be compiled for Windows (using Cygwin and other unix-style tools), but it's not simple.

 

P.S. I wrote an exporter plugin for ArchiCAD to export Radiance scenes, but never finished it. Might be of interest to some.

[AJLynn]

I've tried to compile software in Cygwin before, and it's turned into a giant pain in the ass with anything that's at all complex - I'd rather try to convince the firm to buy me another computer and run Linux or an iMac than try to compile a large piece of software in Cygwin Also it looks like if I were to try to use Ecotect it would want to interface with Desktop Radiance, and unfortunately that looks a bit dated.

 

But thanks - I was wondering whether Desktop Radiance would get an update.

[Ernest Burden III]

apparently the LEED credit calls for Radiance...

 

LEED cert. requires a certain software? Lightscape isn't a possibility (despite the obvious fact of it being out-of-print)?

 

A friend of mine is a green/sustainable architect in NYC (she had to go to Cambridge to get the Masters--no programs in the USA) and she's never mentioned needing Radiance.

[AJLynn]

I can't find the rederence now - my LEED book (v2.2 1st ed.) doesn't mention it by name but the guy who put me up this had a sheet (maybe it was in the errata or rulings - LEED is getting so complicated now I think you'd need a law degree to understand everything) that gave Radiance as a pre-approved simulator and didn't give any others. There are other ways to get through the process - I bet with the vagueness in the book, with enough spreadsheets and graphics Lightscape would work. Good point - I think we do still have a copy or two of Lightscape around here somewhere, and I'm definitely more confident with it.

[stefkeB]

FWIW, the windows version of Radiance in Desktop Radiance still works. The interactive rendering program is not that stable, though.

 

The new version of Radiance (http://www.radiance-online.org/) exists as a precompiled Windows package too.

http://www.dream.unipa.it/dream/pub/dot/anselmo/radiance/03.php

This is compiled from the sources, but uses Cygwin.

 

Another source for the binaries is

http://www.bozzograo.net/radiance/index.php

Try the Mingw binaries (only for the command-line tools, which should be all you really need) for a non-cygwin build.

 

ECOTECT has good Radiance integration. Their Radiance Control Panel is even free to use and they also have a PIC-viewer.

 

I used ConRAD (also discontinued -> used to be on http://www.openentry.dk ) in the past to convert 3ds documents into Radiance scenes. I still have that software here, should that be handy.

 

For OSX, you can use the precompiled binary from Greg ward on http://www.radiance-online.org/

[AJLynn]

That's really useful, thanks. Do you know if the Mingw or Cygwin binaries work with the Ecotect integration? I don't have it to test on...

[stefkeB]

That's really useful, thanks. Do you know if the Mingw or Cygwin binaries work with the Ecotect integration? I don't have it to test on...

I've tried the ECOTECT demo and it was able to run the old Desktop Radiance Binaries. It also seems to work with the Mingw-version, but that misses the rview (interactive rendering) application. There are alternatives, so it is workable.

There were some minor issues with not generating the correct paths in the batch-files (you set up the RAYPATH environment variable, but some of the batch files still look for Radiance in the default path C:\Radiance\bin, which was not where I installed it).

 

I can suggest you to try "SVSAdmin", which is a software administration tool to create "layers" for applications. You can install demo's into a separate layer, so you can clean them up without leaving any traces into your system. This is very useful for testing applications and setups, without a dedicated machine and without a (slow) virtual PC, which is important when you need hardware acceleration and full processor speed. You can activate, deactivate, reset and delete layers instantly. Very good to try out demo's and leave your system clean.

 

There is also Learnix, a Radiance-version on a Linux LiveCD, which comes as a ready-to-boot system. This would be less intrusive on your computer, but might not be that easy to run...

[DisasterArea]

I started to look into using Learnix about six months ago, having been 'using' desktop radiance previously. Simulation is a lot faster using Learnix since I assume it uses the updated Radiance (UNIX) packages.

See http://luminance.londonmet.ac.uk/learnix/

I'm finding it very hard to introduce electric lighting into the calculations though, and can't find any decent descriptions anywhere of the full process especially when using imposter geometry. There is an alternative though, Relux...

 

...Relux which has a pretty good porting of the Radiance package as an addon. Relux is a simulation tool for lighting designers, and in it's basic form is free from www.relux.biz. The radiance tool is an additional tool which requires a payment. The only problem with this is that you need to either build the building in Relux or import it from a 3DS file, and because it is a simulation tool high poly counts will slow the calculation down.

 

Examples of my use of both of these packages can be seen at my webspace;

Learnix - http://www.disasterarea.me.uk/c-viz-48.htm

ReluxVision - http://www.disasterarea.me.uk/c-viz-28.htm