Hydra Interactivity

[stehrani3d]

Hi everyone,
I'm noticing poor interactivity when rendering with VRay through Hydra. Is this normal, and if so, is this something that is still a work-in-progress? Please see the linked video.
Things improve if you drop the resolution to 1/2, 1/4, or further, but Karma remains zippier, and that's not an ideal solution.

Screen-resolution is 4k (other 2 monitors not shown in capture)
CPU is a Threadripper 3960X 24-Core
Windows 10 Pro
Houdini 19.0.498
VRay 5.20.20 (Jan 17 2022)

Thank you.

[david.anastacio]

Hey,

Have you tried turning on the "Export View Continuously" option?



Best,
David.

[stehrani3d]

Hi David, that's interesting. I had not tried tumbling from a locked camera view. See video:
Tumble in perspective view: SLOW
Tumble in locked camera view: Decent
Tumble in locked camera view with Export View Continuously: SLOW

Hopefully Chaos can get the perspective view to behave more like a locked camera. The other thing that would help is to use lower sampling during movement. Karma is much more aggressive with dropping the resolution when you are tumbling/panning/zooming, which helps the viewport feel more interactive. See screenshot.

https://drive.google.com/file/d/1Ie6...ew?usp=sharing

[david.anastacio]

That is very different from what I have.
I don't a performance so slow or so fast as you (I'm using a 3970x).

Maybe the devs can look into it, but in general IPR render in solaris is pretty nice, I even mentioned that to the devs last week because the displacement refresh is very fast in solaris compared to non solaris renders.

best,
David.

[bdancer]

> Hopefully Chaos can get the perspective view to behave more like a locked camera.

https://drive.google.com/file/d/10vl...ew?usp=sharing

Looks not slow at all to me rendering in 3227 x 1562...
Could you please try more recent nightly build? Last week I've optimized writing into Hydra image buffers, may be this'll improve performance for you...

[stehrani3d]

Thank you Andrei, I updated to today's build and it is indeed better! The perspective view now performs well.
That said, I still think Karma is doing the right thing by more aggressively dropping resolution during motion and prioritizing interactivity. If you look at this video (using the latest VRay build) you can see Karma is still faster. What do you think, is it possible for VRay to mimic that behavior?

[bdancer]

> What do you think, is it possible for VRay to mimic that behavior?

I'll check what else could be done.

[glacierise]

Could we plug noise reduction in there? Haven't read about it yet

[david.anastacio]

Could we plug noise reduction in there? Haven't read about it yet

Would be great to have that as a toggle in the render view (solaris viewport). I really don't like how it's currently handled in V-Ray, as a toggle in the ROP. I much prefer the Renderman approach that has a toggle in IT (Renderman render window), you can enable and disable the denoise as the render is running, no restart of the render is needed.

Best,
David.

[glacierise]

That sounds great, as long as there is a hook to add it to?

[bdancer]

> Could we plug noise reduction in there? Haven't read about it yet

The one that is there in the nightlies? Can't add it twice =)

> I really don't like how it's currently handled in V-Ray, as a toggle in the ROP.

What toggle are you talking about? There is no denoise options on ROP in Solaris...
There are IPR denoise options in render view setting and in IPR tab in "render settings" when render settings are used for viewport.

[david.anastacio]

>

What toggle are you talking about? There is no denoise options on ROP in Solaris...
There are IPR denoise options in render view setting and in IPR tab in "render settings" when render settings are used for viewport.

I was referring to non-solaris renders, Render ROP nodes.

[bdancer]

> I was referring to non-solaris renders, Render ROP nodes.

I'll prefer if we'll disduss Solaris only here since it's a dedicated Solaris section.

> I much prefer the Renderman approach that has a toggle in IT (Renderman render window), you can enable and disable the denoise as the render is running, no restart of the render is needed.

I'll log this request, tnx!

[david.anastacio]

Yes, of course, solaris only. I was just using a non solaris example, but the suggestion was for solaris