LuxCoreRender Forums

Since upgrading to 2.1 Alpha3 I have not been able to successfully run a render. I have been getting the error ClBuildProgram when rendering on CPU, GPU, or both. I also get this error if I compile directly after freshly cloning the repositories.
Any ideas on how to fix this?

How did you update and from which version?

rrubberr wrote: Thu Aug 23, 2018 12:59 am Any ideas on how to fix this?

It looks like a problem compiling one (of the very small) OpenCL kernels used by the image pipeline (so it happens with any rendering engine). It happens only to you so it is likely to be something specific of your platform. As first step, you should check if your OpenCL driver is still working by running LuxMark. Sometime, a driver update can break an installation.

Do you have also any other GPU aside from the GTX 1080 ? Like a Intel HD4000 on a laptop (i.e. a GPU known to be unable to run some complex OpenCL kernel).

As workaround, you could disable the OpenCL image pipeline and use the CPU version but I don't know if this option is exposed in Blender

Dade wrote: Thu Aug 23, 2018 1:17 pm As workaround, you could disable the OpenCL image pipeline and use the CPU version but I don't know if this option is exposed in Blender

It was implemented after the v2.1alpha3 release. But if I understand rrubberr correctly, he compiled from the latest sources, so he should have the option.
It was this commit: https://github.com/LuxCoreRender/BlendL ... 6d468f8df2
https://github.com/LuxCoreRender/BlendL ... 3...master
You can find the checkbox in the camera properties, imagepipeline panel.

Dade wrote: Thu Aug 23, 2018 1:17 pm

rrubberr wrote: Thu Aug 23, 2018 12:59 am Any ideas on how to fix this?

Do you have also any other GPU aside from the GTX 1080 ? Like a Intel HD4000 on a laptop (i.e. a GPU known to be unable to run some complex OpenCL kernel).

I can confirm that it does not work with Nvidia OpenCL, OpenCL on my Xeons, or OpenCL on my Vega FE card (AMD drives).

B.Y.O.B. wrote: Thu Aug 23, 2018 1:25 pm

Dade wrote: Thu Aug 23, 2018 1:17 pm As workaround, you could disable the OpenCL image pipeline and use the CPU version but I don't know if this option is exposed in Blender

It was implemented after the v2.1alpha3 release. But if I understand rrubberr correctly, he compiled from the latest sources, so he should have the option.
It was this commit: https://github.com/LuxCoreRender/BlendL ... 6d468f8df2
https://github.com/LuxCoreRender/BlendL ... 3...master
You can find the checkbox in the camera properties, imagepipeline panel.

I have just done a fresh compile, so I'm sure I do have that option, but while that is a workaround you can't beat the speed of Lux OpenCL rendering

rrubberr wrote: Thu Aug 23, 2018 8:25 pm but while that is a workaround you can't beet the speed of Lux OpenCL rendering

We are only talking about the imagepipeline processing (taking the raw film and applying all imagepipeline plugins like tonemapping, bloom, vignette etc.).
You can still render with the OpenCL engines, the option only forces to use the CPU for the imagepipeline because that is apparently what's throwing the error in your case.

rrubberr wrote: Thu Aug 23, 2018 8:24 pm

Dade wrote: Thu Aug 23, 2018 1:17 pm

rrubberr wrote: Thu Aug 23, 2018 12:59 am Any ideas on how to fix this?

Do you have also any other GPU aside from the GTX 1080 ? Like a Intel HD4000 on a laptop (i.e. a GPU known to be unable to run some complex OpenCL kernel).

I can confirm that it does not work with Nvidia OpenCL, OpenCL on my Xeons, or OpenCL on my Vega FE card (AMD drives).

But are you using the v2.1alpha3 available in this forum or binaries compiled from the latest sources ? There has been some not trivial change in OpenCL code in the latest sources.

Dade wrote: Thu Aug 23, 2018 10:48 pm

rrubberr wrote: Thu Aug 23, 2018 8:24 pm

Dade wrote: Thu Aug 23, 2018 1:17 pm
Do you have also any other GPU aside from the GTX 1080 ? Like a Intel HD4000 on a laptop (i.e. a GPU known to be unable to run some complex OpenCL kernel).

I can confirm that it does not work with Nvidia OpenCL, OpenCL on my Xeons, or OpenCL on my Vega FE card (AMD drives).

But are you using the v2.1alpha3 available in this forum or binaries compiled from the latest sources ? There has been some not trivial change in OpenCL code in the latest sources.

I have just run another compile (about 10 minutes ago), and I'm starting to think it's just a slightly broken OpenCL driver, because while Luxmark works, the Julia4d OpenCL test in MSI Kombustor also has errors. I will try reinstalling and report back.

*UPDATE*

Nope, I get the same error with a different, clean-installed driver version as well, perhaps it is an issue on Nvidia's end, though.

If you install the v2.1alpha3 available here: viewtopic.php?f=9&t=538

Do you get the same error ?