What's the point of a GPU render in Vray??

[ajlan_altug]

Out of 204 CPU features, less than half (94) are supported (I marked partial supports as 0.5 instead of 1) for GPU. If this is the case, what's the point of having a GPU engine in the first place if it's development is seemingly progressing this slow? (Less than half of supported features in 7 years of development)

Blender is an open source software and Cycles's GPU/CPU discrepancy is absolutely 0% in all fronts, where CPU is also used for support in GPU mode.

Does a Vray user have to have the GPU limitations page open at all times in a browser window as he/she is working away so as to constantly check whether the feature/node they need is supported in GPU mode? It seems to me that the only viable and failsafe method Chaos can offer is working and rendering strictly in CPU mode in this day and age?

For truly heavy and complex scenes, IPR'ing on CPU is a nightmare endeavor. I was literally dumbfounded when I saw how many unsupported features GPU mode has at this time.

For a freelance artist like myself, this makes rendering out medium and sometimes heavy weight scenes on your local PC an almost impossible proposition.

I really liked Vray, quite a lot... But at every corner along the way, it's getting me more and more dismayed

[oglu]

We use GPU a lot and we dont have any issues. We dont need most of the features that arnt supported.
If you have impossible to render scenes share them here. A lot of time there is an easy fix to make it render.

[glorybound]

I have some issues with GPU rendering, but compatibility isn't extensive. When it works, it works well.

[Morbid Angel]

I think the consensus is that gpu is a promised land, where in reality does not live up to offer the benefits it promises/pretends to do. Yes in some cases its faster, but in the grand scheme of things you need a really rockstar gpu to make a difference which can cost a lot and become outdated very fast. In our environment, using gpu is not possible for many reasons and this can be different for arch-rendering, where you mainly render exterior/interior as a single frame. We have to render each shot 10-20 layers, with mattes, shadows, volumes, hair etc and I don't even dare to venture into gpu world, mainly due to time constraints. I know cpu gets the job done, a bit slower yes, but I'd rather kick off a render and walk away, then spend hours sitting down fixing a problem with gpu.

[glorybound]

I agree with what you are saying Morbid Angel! I dropped another $2000 grand on my second RTX 4090, and I am getting 4K stills in less than an hour, which I couldn't come close to using my CPU. Spending my money on a better CPU would have probably been better, but as you said, I bought into the GPU hype. I had to ditch my render elements to get under an hour of GPU rendering, which I think is a significant loss. For my exteriors, CPU all the way!

[glorybound]

4K in 9 minutes on 2-RTX 4090's - When it works, it works well!

[Muhammed_Hamed]

I had to ditch my render elements to get under an hour of GPU rendering, which I think is a significant loss. For my exteriors, CPU all the way!

Being at the top of our priorities, we will put effort into this again this year. I hope there will be a solution/improvement.

I dropped another $2000 grand on my second RTX 4090,

Threadrippers are very expensive these days sadly, to put this into numbers if you want 3x the performance of your current CPU you will need to pay 2500 USD for the CPU alone, in this case the 7970x. And around 1100 USD on system memory and motherboard.
If you go for the 64-core Threadripper, it will be 5000 for the CPU alone...

[Muhammed_Hamed]

If you have impossible to render scenes share them here. A lot of time there is an easy fix to make it render.

+1, I would love to take a look as well

[Muhammed_Hamed]

Out of 204 CPU features, less than half (94) are supported (I marked partial supports as 0.5 instead of 1) for GPU.

Updating this page as we speak, I will post here again when this is finished(there is also a big update to the docs, that has been in the making similar to what we did with our support portal)
FYI the supported features page misses on most of what we did this year and last year.

On another note, some of the CPU only features will not be ported to GPU. For GPU rendering, we are limited to what the CUDA/Optix APIs allow us to do, for example Progressive Caustics will not make it to V-Ray GPU. We have a brand new Caustics solver written from scratch to work as fast as possible on GPU, it will be out soon.
Next we will be working on Toon Shading in V-Ray GPU, most likely we will have something different to what V-Ray currently have.

V-Ray is being used in many industries, ArchVis, Entertainment, product design and so on. V-Ray has many features and dozens of shaders and procedurals, we don't plan to port every single one of them to GPU, this is not the goal(and it is not possible)
If there is a feature or shader you want to be supported for your workflow, let me know. Our roadmap is based on user feedback/requests

Best,
Muhammed