Quote - With GPU rendering, its pretty much manadatory. 

I'm sorry but I have to make a distinction here. Texture collection is only necessary with SLG, it should not be used for rendering with Lux, even with GPU enabled.

SLG loads everything, geometry and textures in the GPU. Because of this, it is necessary to collect and reduce the textures because, at 2K or 4K per texture, you exhaust the GPU memory very easily. It has nothing to do with speeding up, it is a matter of fitting the textures in memory. There is, obviously, a degradation of quality but that's all that we can do until we can get GPUs with 4or 8 GB of RAM.

Lux doesn't use the GPU for the textures, it takes advantage of the extreme soeed of the GPU in crunching floating point operations to make the raytracing portion faster. All the textures are kept in the main memory and so they can be used at full resolution.

So, when using Lux with GPU acceleration you should turn OFF texture collection. Of course, there is another use for texture collection, and that is to make it possible to tramsfer your Lux scene to another machine. That has nothing to do with GPU or not and it should be used as you prefer but generally you want to set the size of the textures to the original.

Hope this helps.

Paolo

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