RT Questions & Answers

[Donfarese]

Here are some of the Questions for users of RT are wanting info on. I figured I’d put it all in one place. We built our systems to fully render on RT, we are more than impressed with the speed and interactivity of the renderer. But after diving into a few projects we found RT unusable do to its lack of support for basic and everyday used features. We want to see this progress and grow, not only because we invested into GPU’s but because this seems to be the future. I tried to put the questions in number of importance.



1) When will Bump Mapping and Reflection mapping be fixed? (RT is pretty useless without this)

2) When is the ram display or ram issue going to be fixed? Still shows RT using 2x the ram than ADV.

3) Procedural maps will be a huge plus if we can get those to work for Bumpmap slot? But “1” needs to be fixed first.

4) Why is RT Cpu so limited. We have Progressive rendering in ADV, why can’t that be made to just continuously render? Corona has a great CPU interactive renderer showcasing this. This would be huge.

5) Irradiance map would be great on GPU for the speed. What does the timing look like on this though?

6) What more as users can we provide to help this along? With pascal coming out with 32gb of ram, I see the way of the Cpu gone if GPU supported everything. The speed difference is immense compared to Cpu’s which don’t seem to be gaining much speed at all with every new release.

7) Forest pack pro is a huge part of Vray user’s workflow, how can we get better support for it in RT for its shaders?

When is the next release of service pack that addresses RT?



Thank you Chaos Group, Vray is one impressive renderer!

[vlado]

I can't really give you any timings, but I can answer #4:

We have Progressive rendering in ADV, why can’t that be made to just continuously render?

Of course it can be done and it's somewhere on the roadmap. But I wanted to delay this for two reasons:

a) It would require a lot of changes to the advanced renderer; newer versions of 3ds Max seem to have special APIs that make interactive rendering easier to implement and I wanted to use that API so that we don't have to redo things all over again. In the meantime, V-Ray RT CPU seemed like a not-so-bad compromise for adjusting lighting and overall materials, when you don't need pixel-perfect match with the advanced renderer. Also worth mentioning, this discrepancy is present only in 3ds Max; for other V-Ray integrations (Maya/Modo) V-Ray advanced and V-Ray RT CPU produce exactly the same results, 1:1

b) Like I said, doing a) is somewhat complicated (and, as mentioned only really a problem for 3ds Max, due to the tight integration of the advanced renderer with the 3ds Max rendering API), and it makes more sense to focus on V-Ray RT GPU - as you said yourself, that technology shows way more promise. Facing the choice of whether to spend efforts on rewriting the advanced renderer, or implementing RT GPU, I decided to focus on the second part and leave the work on the advanced renderer for later - RT GPU still needs a lot of work to be usable.

Best regards,
Vlado

[Donfarese]

Very interesting, never knew that there was a difference with Maya & 3dsmax RT Cpu because of a 3dsmax issue. I am not a programmer so don't know how complicated making the progressive renderer interactive is, But I do agree efforts should be placed on the V-Ray RT GPU. Thanks for the update Vlado.

[sheehan_partners_nm]

Maybe this question was answered before but I could't find it,...is the new IPR with Vray 3.5 going to use distributed rendering for more interactive power? Just like GPU RT ?

[Alan Iglesias]

Maybe this question was answered before but I could't find it,...is the new IPR with Vray 3.5 going to use distributed rendering for more interactive power? Just like GPU RT ?

I believe I have read that the answer to this question is no, IPR will not use DR.

-Alan

[vlado]

We do not plan to support DR for the IPR mode, at least for now.

Best regards,
Vlado

[sheehan_partners_nm]

Thank you Vlado and Alan for your responses. I hope this comes in the future then. It would be great to have instant power from so many CPU all together.

Cheers and have a good week guys!

[savage309]

Ah, nice to find this post from some time ago.

We can do a recap of what changed since then:
1. This is fixed.Procedural bump maps work fine in 3.5.
2. This is fixed.
3. This is fixed.
4. Vlado answered and IPR is here.
5. This is fixed.
6. Giving feedback is the most important. For the memory, we have the on-demand mode now, that allows fitting more memory-demanding scenes on the GPU.
7. This is fixed.
8. I guess this is it !

Best,
Blago.

[algato]

Hello,

can I reduce the on demand mip-map preparation time of the textures when I save the textures before as tx files ?
Can RT save the prepared mip maps and later reuse them ?

Kind regards
Alex

[savage309]

Hello,
can I reduce the on demand mip-map preparation time of the textures when I save the textures before as tx files ?

Unfortunately this will not help.

Can RT save the prepared mip maps and later reuse them ?

We don't have this option at this time, but it is a good idea !

Best,
Blago.

[algato]

Hello,
it would be good, to have a texture converter which allows to prepare the maps by a manually selection of files in a directory.
Similar to the maketx tool, or the image to tiled multiresolution EXR converter.
The VrayHdri bitmap loader should be able to read that specific format for use the maps in RT and in Vray Advanced also.

Kind regards
Alex

[eligiusz]

I second that, it would be desireble to have Your assets RT ready.

Right now i'm in the process of converting all the big textures to .tx to reduce ram consumption, wonder how it will perform on GPU ?

Also how are the .exr files handled in RT? are they also converted before render ?

[savage309]

I second that, it would be desireble to have Your assets RT ready.

Right now i'm in the process of converting all the big textures to .tx to reduce ram consumption, wonder how it will perform on GPU ?

Also how are the .exr files handled in RT? are they also converted before render ?

The texture format does not make difference for V-Ray GPU.

Best,
Blago.

[eligiusz]

will exr and tx textures still be converted to the internal mipmap format, everytime when I start a render ?

My idea here is, to build assets with already prepared textures, so that the mipmap convertion will not be executed everytime

[savage309]

will exr and tx textures still be converted to the internal mipmap format, everytime when I start a render ?

My idea here is, to build assets with already prepared textures, so that the mipmap convertion will not be executed everytime

The GPU will prepare them in the internal format when using On-Demand mip-mapped texture, yes.
Does it take a lot of time ? It shouldn't be that long.

Best,
Blago.