LuxCoreRender Forums

So for a while, ever since Lux 2.4 came out actually, I've been getting an error in my renderings where materials just straight up don't render, it's just black.

After doing some testing I've found that materials will render as long as I'm not rendering with GPU Hybrid tracing, all other rendering on CPU, GPU, Path, Bidir, CPU Hybrid, works just fine.

I've also found that it's the normal maps that's likely causing the material blackout, using the displacement map or even the blue channel of the normal map with a bump node works just fine. Heck, even just plugging in the normal map as an RGB image into the material still renders without blacking out. So it's only when the "Normal Map" is checked in the image does the GPU Hybrid tracing fail.

Is there anything I can do to fix this, or is this a bug with 2.4? Normal maps worked just fine in 2.1-2.3 and blender 2.79-2.83 and I wouldn't be surprised if normal maps in 2.3 still worked in 2.90

Also, I'm rendering on an Ryzen 7 3700X and RX 570 with the latest AMD Radeon Drivers (20.9.2)

Here are some images form my testing, I'm more than willing to share more images and even the blend file if asked

GPU Path Tracing w/ Normal Map:
GPU Hybrid Tracing w/o Normal Map:
GPU Hybrid Tracing w/ Normal Map:
GPU Hybrid Tracing w/ Normal Map as RGB Image ("Normal Map" unchecked):
Thank you for the help!

It is like to be the known problem with AMD drivers and normal map code: the same code work fine with NVIDIA and Intel OpenCL so I assume it is a AMD driver bug.

v2.3 and v2.4 GPU code is radically different because v2.4 doesn't require a kernel recompilation for each scene anymore (it is compiled only once however it looks like it is too complex for AMD compiler).

yeah, it's probably a driver issue

damn.

thank you for the help, though!