LuxCoreRender Forums

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am I’d like to have a go at the Luxcore Blender 2.8 beta, but I’ve got a few questions:

[*]Does Luxcore work with the latest 2.81 master builds?

It works with 2.80 official release, it may work with v2.81 but I haven't yet seen any report about that.

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am [*]Luxcore uses OpenCL, and no NVIDIA libs such as CUDA or OptiX, or am I mistaking?

Correct.

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am Does OpenCL match the speed of the NVIDIA libraries when rendering with an NVIDIA GPU?

NVIDIA wrote its OpenCL drivers over CUDA so there some overhead and OpenCL is slightly slower (on NVIDIA GPUs). But the difference in term of features/caches/etc. when comparing with Cycles, etc. is usually far larger than overhead.

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am [*]Does Lux support vertex colors?

Yes.

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am [*]Does Lux have blended box or tri-planar mapping?

Lux uses UV vertex coordinates exported from the application so the answer is no (or, may be, yes if you bake the mapping on UV vertex coordinates).

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am [*]Can you layer multiple HDR environments using an Add shader, like in Cycles?

Lux supports any number of environment light sources (HDR, sun, sky, etc.).

MetinSeven wrote: ↑Sun Aug 18, 2019 10:23 am [*]Does Lux have Random Walk SSS?

Yes, it is the only method Lux has ever used.

Thanks a lot for your answers, Dade, much appreciated. I'm going to try if the Luxcore beta works in the latest Blender 2.81 master build.

The Luxcore beta for Blender 2.8 seems to work fine in the latest 2.81 beta.

My first test results look great. I love the realism. I used Luxrender for a while, years ago, but Luxcore looks and feels much better. Great work.

A few newbie questions:

Why is the rendering engine drop-down menu greyed out when you've switched to OpenCL?
If only one engine works, which of the two works with OpenCL?

A lot of material nodes don't work with the Bidirectional engine. Is this because of the beta stage?

I noticed that Blender's Auto Smooth does not seem to work, resulting in artifacts in Booleaned meshes. But maybe that's just a Lux setting somewhere?

I also noticed that switching from OpenCL to CPU results in a slightly darker rendering. What could be the cause of that? No other settings were changed.

Is there an option to override the world background? So reflections, lighting and refractions remain, but you see a different background.

Thanks.

MetinSeven wrote: ↑Sun Aug 18, 2019 1:26 pm The Luxcore beta for Blender 2.8 seems to work fine in the latest 2.81 beta.

My first test results look great. I love the realism. I used Luxrender for a while, years ago, but Luxcore looks and feels much better. Great work.

A few newbie questions:

Why is the rendering engine drop-down menu greyed out when you've switched to OpenCL?
If only one engine works, which of the two works with OpenCL?

A lot of material nodes don't work with the Bidirectional engine. Is this because of the beta stage?

I noticed that Blender's Auto Smooth does not seem to work, resulting in artifacts in Booleaned meshes. But maybe that's just a Lux setting somewhere?

I also noticed that switching from OpenCL to CPU results in a slightly darker rendering. What could be the cause of that? No other settings were changed.

Thanks.

OpenCL can only do pathtracing not bidir

There is some problem currently exporting custom normals to luxcore. So booleans and imported cad meshes will have issues. You can clear custom normals in mesh menu in blender but then you can only use autosmooth which can result in some shading issues with booleaned or imported cad models as a "workaround" you can split mesh where you need hard edges but I really hope that custom normals will be supported.

Thanks Lacilaci!

Also, bidir is a bit limited with features, for example shadow catcher won't work. However if you need caustics then lighttracing option in render settings will be much faster than bidir.

Clear, thanks!

MetinSeven wrote: ↑Sun Aug 18, 2019 1:26 pm Is there an option to override the world background? So reflections, lighting and refractions remain, but you see a different background.

Yes, it should be the "Transparent film" option under the "Camera" panel: viewtopic.php?f=4&t=1100&p=12845&hilit= ... ilm#p12845

Great, thanks!

lacilaci wrote: ↑Sun Aug 18, 2019 1:32 pm

MetinSeven wrote: ↑Sun Aug 18, 2019 1:26 pm The Luxcore beta for Blender 2.8 seems to work fine in the latest 2.81 beta.

My first test results look great. I love the realism. I used Luxrender for a while, years ago, but Luxcore looks and feels much better. Great work.

A few newbie questions:

Why is the rendering engine drop-down menu greyed out when you've switched to OpenCL?
If only one engine works, which of the two works with OpenCL?

A lot of material nodes don't work with the Bidirectional engine. Is this because of the beta stage?

I noticed that Blender's Auto Smooth does not seem to work, resulting in artifacts in Booleaned meshes. But maybe that's just a Lux setting somewhere?

I also noticed that switching from OpenCL to CPU results in a slightly darker rendering. What could be the cause of that? No other settings were changed.

Thanks.

OpenCL can only do pathtracing not bidir

There is some problem currently exporting custom normals to luxcore. So booleans and imported cad meshes will have issues. You can clear custom normals in mesh menu in blender but then you can only use autosmooth which can result in some shading issues with booleaned or imported cad models as a "workaround" you can split mesh where you need hard edges but I really hope that custom normals will be supported.

Actually it does look like autosmooth is now not working at all in 2.8 (ignores autosmooth angle value). We'll have to wait for B.Y.O.B. to come back from vacation to fix that