GPU and emissive materials

Pipperox · Post by **Pipperox** » Fri Nov 02, 2012 11:52 pm

Hi,
I've noticed that if i enable GPU rendering (OpenCL), emissive materials (which i use as light sources) are not rendered.
They still light up the scene though, just the emissive objects themselves are invisible.

If i use the same Path algorithm, but running on the CPU, then the scene is identical, except for the emissive objects which are now visible (and glowing).

Is this a limitation of OpenCL rendering, or am I missing something?

Thanks,

Zom-B · Post by **Zom-B** » Sat Nov 03, 2012 12:07 am

Do you use sphere primitives as light sources??!
The GPU tracer doesn't support Primitives, so no mesh is exported with no light material on it if you do so.
Als better try to create loooow poly spheres convert to mesh for faster rendering.
Less polys for emitters = better!

Pipperox · Post by **Pipperox** » Sat Nov 03, 2012 1:56 am

Yes, that was exactly the problem, thank you!

Zom-B · Post by **Zom-B** » Sat Nov 03, 2012 6:34 am

Pipperox wrote:Yes, that was exactly the problem, thank you!

You are welcome

Maybe you could post that issue for the relevant Exporter Subforum in the latest release thread so it gets fixed.
(fixing = convert spheres with emitter mats to mesh if GPU export is activated)

Pipperox · Post by **Pipperox** » Sat Nov 03, 2012 6:37 am

Haha, no there isn't any relevant exporter, I scripted the scene by hand in XML.

Zom-B · Post by **Zom-B** » Sat Nov 03, 2012 7:30 am

Pipperox wrote:Haha, no there isn't any relevant exporter, I scripted the scene by hand in XML.

crazy you ^^
remembers me like for Indigo 0.5 there was a low end exporter from C4D, and I had to hack a lot inside the XML to change camera view etc.
I even don't dare to ask why you don't use at least Blender or Sketchup

CTZn · Post by **CTZn** » Sat Nov 03, 2012 10:20 am

Why don't you use blender or SketchUp ?
/*angel mode off*/

Pipperox · Post by **Pipperox** » Sun Nov 04, 2012 4:01 am

Short answer: because i'm an engineer, not an artist.

Longer answer: my scene is simple, but it's procedurally generated and i need full control on the dimension and positions of my objects.

While sort on topic: are there any plans to support CSG in future releases?
CSG is great to generate procedurally complex scenes, for example for scientific visualizations.
So far i was using POVRay exactly for this purpose, but i'm moving to Indigo due to the physical light simulation and greatly increased realism.

Zom-B · Post by **Zom-B** » Sun Nov 04, 2012 4:10 am

There was some work doe for implicit surfaces and parametric surface.

CTZn · Post by **CTZn** » Sun Nov 04, 2012 8:57 am

There is also the possibility to substract from participating media using an 'air' medium.

I don't remind that CSG was requested ever. I'm not the developer you want to talk to but I naively tend to believe that implementing it for primitives and other implicit surfaces would be a good start.

I wouldn't mind having a peak at an engineer's work someday

Headroom · Post by **Headroom** » Sun Nov 04, 2012 12:54 pm

Bad excuse! I've been an engineer for over 20 years and have used Blender for about 10 years.

To be honest, however, the transition from a feature to an edge loop took a while to sink in. Maybe I need to make a tutorial. Blender for Engineers