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This is a normal post I only dabble so it's not worth paying for anything,
but I've seen some impressive images created in it.

Also I really like typing the co-ordinates in instead of having to faff around with the mouse and doing things by eye.
 (I helped save b3ta! Moon Girl Technologies horrendous beanbag, Fri 8 Feb 2013, 12:47, , Reply)
This is a normal post The CSG engine and scripting side is nice enough to use
It's the back end and implementation I've got no time for. CSG trees get unwieldy quite fast, and the use of implicit geometry for everything has been hobbling the performance for years.

By all means use CSG, but FFS expand the geometry, stick it into some *decent* spatial data structures and take a tenth of the time to render a scene!

[edit] They can't actually do this, because the CSG engine allows infinitely large objects. This means that to have something with decent performance for, say, triangle meshes and tessellated objects they need to support 2 data structures simultaneously and decide what can be expanded on a per subtree basis. Don't envy them but they brought it on themselves.
 (tacpprm has a mmrpcat, Fri 8 Feb 2013, 12:55, , Reply)
This is a normal post development has sadly ground to a halt,
the latest version with SMP has been in beta for frickin' years.
 (I helped save b3ta! Moon Girl Technologies horrendous beanbag, Fri 8 Feb 2013, 13:01, , Reply)
This is a normal post Really?
Ray tracing is pretty much the poster child for "SMP is easy". WTF have they been doing?

Actually I can guess. Globals all over the place instead of passing context around properly.
 (tacpprm has a mmrpcat, Fri 8 Feb 2013, 13:07, , Reply)
This is a normal post it seemed to work fine, when I tried it,
annoyingly they put a time limit on it though so you had to download a key to renew it every so often, for reasons I can't fathom. Fine if they actually expected it to come out of Beta within that time limit. Urgh.

I think it's because they added a lot of experimental features all in one go and haven't had the time to develop any of it.
 (I helped save b3ta! Moon Girl Technologies horrendous beanbag, Fri 8 Feb 2013, 13:13, , Reply)
This is a normal post Reminds me that I should get back into writing renderers.
I kind of got bored with it after I had been doing it for pay for a few years. I had a scheme to do a new hybrid MC/hardware renderer, but then got sidetracked and spent the last few years working on the tone mapping instead :)
 (tacpprm has a mmrpcat, Fri 8 Feb 2013, 13:20, , Reply)
This is a normal post hardware raytracing in FPGA pls!
I read a paper by a group who did that a few years ago, really impressive performance. As much parallel processing as you can shake a stick at.

It's funny how doing something for a living destroys your enthusiasm for it, though. I know this effect too well.
 (I helped save b3ta! Moon Girl Technologies horrendous beanbag, Fri 8 Feb 2013, 13:22, , Reply)
This is a normal post Problems with going the fpga route
1. fpgas are still pretty pricey

2. my current machine is a laptop, and /laptop/ fpgas are limited.

3. ray tracing needs random access to the whole scene. You either need to keep the whole scene in mem or have some paging system.

4. Data transfer is expensive. Whatever job you are offloading has to really be worth the effort.

3 and 4 are the biggies there. Interesting scenes are absurdly complex these days, and even gpu memory is limited. Not saying it can't be made useful, just that you need to think hard about what to offload.

Now if you offload the post render tone mapping you could probably do very well. I have been coding up a QMC based approx bilateral filter lately that gives excellent results and would work nicely in hardware.

When finished it's going to take pride of place in the middle of my detail enhancer. Same results as the old one, much faster :)
 (tacpprm has a mmrpcat, Fri 8 Feb 2013, 13:36, , Reply)
This is a normal post 1. depends on spec. but they can be.
3 & 4 true, but, hmm... I wonder if a scene can be split up in some way and then composited afterwards.
 (I helped save b3ta! Moon Girl Technologies horrendous beanbag, Fri 8 Feb 2013, 14:12, , Reply)
This is a normal post Yes, but with difficulty.
The problem is that after the first bounce a ray can end up anywhere in your scene, especially if you are doing lighting simulation or lots of reflections.

One approach is to split up the scene into regions and have a processor/machine/fpga dealing with each one, but then you have to deal with the problem of handing over rays between regions and routing results back to whatever asked for them.

The details get a bit horrible.
 (tacpprm has a mmrpcat, Fri 8 Feb 2013, 14:16, , Reply)