LuxCoreRender Forums

Been a while that I wanted to test some basic nature scenes in Lux, and now it's easier than ever thanks to it being able to use simple Cycles nodes, so I gave it a try. The only problem I hit was OpenCL basically filling my whole RAM and half of swap files and then crashing (some 24GB in total) despite CPU and Cycles on GPU (CUDA) working just fine without even needing any swap.

Around 100K particles and 8.5M vertices.

Looks lovely!

Looking good!

the blurred background really adds to the mood, nicely done!

That is really nice and will be nice in the gallery. I'm a bit concerned about the high memory usage. Normally opencl compilation happen just one time for first render in 2.4 alpha but the displayed message wasn't update yet.
8.5 million vertices seem small to me. I wonder why it took so much memory.

Looks awesome

Superb image, loving it.

Sharlybg wrote: ↑Fri Apr 10, 2020 5:49 pm I wonder why it took so much memory.

It is something we have already seen: particles are like any other object in LuxCore and there is a fixed (memory) cost for each object. This cost is small and negligible for normal meshes but start to be a noticeable overhead if the object is very simple (few triangles). For instance, a work around, is to not instantiate the single blade of grass but a small tile.

Dade wrote: ↑Sat Apr 11, 2020 8:54 am

Sharlybg wrote: ↑Fri Apr 10, 2020 5:49 pm I wonder why it took so much memory.

It is something we have already seen: particles are like any other object in LuxCore and there is a fixed (memory) cost for each object. This cost is small and negligible for normal meshes but start to be a noticeable overhead if the object is very simple (few triangles). For instance, a work around, is to not instantiate the single blade of grass but a small tile.

Hmm, but 100k particles arent much and 8.4m poly is nothing.
There might be a problem in hows the scene setup thhough.

Thanks everyone!

Sharlybg wrote: ↑Fri Apr 10, 2020 5:49 pm That is really nice and will be nice in the gallery. I'm a bit concerned about the high memory usage. Normally opencl compilation happen just one time for first render in 2.4 alpha but the displayed message wasn't update yet.
8.5 million vertices seem small to me. I wonder why it took so much memory.

There are many high-res textures so it's explainable to a great degree, but I'm not aware of the technical details so not sure why OpenCL needs so much more memory compared to CUDA for example (roughly some 50% more without any textures for example).
But yes I feel like 16GB of ram is pretty much nothing both for Blender itself and render engines these days.