1) Is this performance on cpu, how the engine updates in ipr, is this to be expected on a very simple scene like this? Any tips on how to get a much more responsive experience?
2) The ipr in 3ds max viewport is horrible. Is this a 3ds max problem?
My cpu: Threadripper 3970x
128 ram
thanks
This is exactly how it is for me. IMO Corona is miles ahead in this area. It’s so much more responsive and stable during realitime.
I never even bothered with the IPR viewport. I use IPR with every project but before I switch it on, I turn off displacement, forest packs, and everything else a bit heavy. I only use it to test different lighting scenarios, which is a tiny bit faster than having to start/stop the render, but not a lot. Agree it can do with a performance upgrade.
Stability wise it got a lot better (I haven’t experienced that much crashes), but there’s still a lot of unnecessary refreshes when nothing changed, and sometimes no refreshes when a couple of things already changed.
For what Im seeing in the video that is not normal behaivior, specially from the quantity of objects in the scene. They dont even have materials, right?
For me its quite the opossite, using Corona IR Its very frustrating, very laggy (exactly like the video), irresponsing, many times Max crashes.
I use both and I have very harsh times when I use Corona. Many of the issues deppend on the PC Specs, where I work its impossible and the developers cannot find a solution in my case.
its just a simple plane, with noise, no materials.
So for you, you do not have this issue? IS this because my cpu is old?
Any devs here that can give me/us some more info on this?
Old…I have both 3970x and 3990x, in years they might seem old but current comparable threadrippers after 5 years aren’t all that better are they?
do you use 4k monitor by chance?
Does that matter if you run IPR (not in viewport of course) in as low as resolution as OP (1132 x 637)?
Im on a 2k monitor.
Try lowering the viewport IPR resolution (default=1) via the following line; it should help with the responsiveness:
renderers.current.ipr_viewport_resolution=0.5
One thing that helped speeding up IPR sessions for me was setting Brute Force as secondary GI solver.
That way the Light Cache lag is gone.
I am on brute force for secondary GI.
IPR is definitely not that slow by design (nor it ever is for me, compatibly with scene complexity, to a degree.).
See here on a 7950X.
Regardless of CPU and architecture differences, the interrupts and pickup ought to be well instantaneous (while convergence ofc will take longer for the slower system, so you’d see some more black pixels.), you may have other issues afoot.
Well, I have never seen IPR in V-Ray that fast. Not even on a teapot scene.
thanks for the reply.
issues like what? What should i check? I have never seen ipr that fast in vray.
Umh, this is very surprising.
The performance for me was always analogous to this one, with the obvious caveats (of cpu speed and scene complexity.).
Does having the LC as secondary engine helps?
Issues for this kind of stuff could be callbacks from one or more other plugins/scripts that interfere with the message passing from the DCC to IPR.
They could be doing -literally- anything to the open max: check a license, open a file on disk, iterate through all the nodes in the scene and do something.
There is hardly any limit, and they are executed when the appropriate event triggers them: f.e. a viewport change could trigger some operation in some callback.
Some lay dormant forever (f.e. the swathe of physX stuff.), some may be nagging you as IPR is not free to start rendering until the DCC (max) told it that it is, and callbacks may delay that.
See if this happens identically on a fresh max install + only V-Ray, this ought to give us all a better clue as to what it may be.
I have never seen IPR that fast either as a matter of fact. TR 3990x and 3970x. Weird. Might do some testing.
Well, fresh install on 3ds max 2026, no other plugins or scripts and with simple teapots scene. It is no near responsivness I see in this video Lele. I am on amd 9950x.
Me too. I have never ever seen Vray that fast before. Corona, yes. Vray, no.
I’m exaggerating of course, but perceptively I feel like mine runs much much slower than what Lele has shown.