What's the minimal requirement for Daz's iray preview to work?
Griffin Avid
Posts: 3,822
Imagine a 1080 ti card + what processor......
The nVidia card does the rendering and the CPU does the scene and such, BEFORE rendering.
So I'm asking what kind of processor works in real time in conjuction with a 1080 ti?
As far as I understand RAM controls how big the scene can be- as in loading the ENTIRE scene in memory.
But live preview is like a mini-render...continuously....
So does anyone have a rig that does iray live preview?
----
And I mean a set + some figures....pick any house or room set and two Gen 3 or Gen 8 figures clothed in a full figure's set of wears....
As an example.....
Daz 3D is part of 
Connect
DAZ Productions, Inc.
7533 S Center View Ct #4664
West Jordan, UT 84084
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2025 Daz Productions Inc. All Rights Reserved.
Comments
Not sure what you mean by "live preview". I use the iray preview for every scene i am working on. I have an i7-6700K with a GTX 980. My scenes usually involve a room with a couple of clothed figures, but it also depends on other factors. My rule of thumb based on my experience, is if the scene is to complex to use preview mode, then it is too complex to render and I then start to optimize it.
Not sure what you mean by work, if you mean as smooth and constant as the openGL preview I got no idea, but it works for me on a fx-8350 and a gtx1060 it just takes a few secondos to render the scene again if i move the camera or change stuff on the scene.
Subjective short answer:
It may not be a matter of your system but a matter of how the "Iray live preview" viewport does not (yet) seem optimized to preview parameter changes in real time.
Other render engine solutions had substantial (re) work to improve how the scene is calculated to allow for quick preview viewports.
- - -
Subjective example
On the computer one GTX 1080 and two GTX 1080 Ti are installed.
I have set both GTX 1080 Ti to render in Nvidia Iray. I assume that both GTX 1080 Ti would be used to calculate the Iray preview viewport.
No matter which "Draw" settings I try unless I have just one figure without hair in the screen it seems impossible to see the results of adjustments of any sliders in "real time".
compare:
https://www.daz3d.com/forums/discussion/166886/nvidia-drawing-style-which-settings-for-real-time-viewport
Adjust a slider. Wait for the live preview to update. Try another value. Wait for the live preview to update.
It does not help the cause that in its current integration the scene of the preview viewport is not kept in GPU memory.
If you switch to another draw style like "texture shaded" (to change a pose in OpenGL mode) and then back to "Iray preview" the whole scene has to be reloaded into memory.
Compared to other render engines at least the Iray implementation in DAZ Studio just does not (yet) to seem optimised for time efficient (!) real time scene setup work.
- - -
Workarounds:
- Create a sub scene for each character or major scene element. Adjust material settings one element at a time in the sub scenes.
- Try to set up and test the main "environment" lighting with simple elements like cubes and planes.
- Combine every sub scene and the main scene as a last step.
- Use the spot render tool to check critical areas
- - -
Subjective commentary:
To me it is unclear if DAZ and Iray staff are fully aware of the current limitations.
Maybe if people have just worked with Iray they do not know anything else and do not mind the waiting times.
If you have worked with other solutions the delays in viewport updates and the time it takes to reload scenes into GPU memory are noticeable.
I submitted a support ticket to ask for improved Iray features just last week.
Feature request for Iray updates seem to be passed on to DAZ Staff.
But further than that there is no information provided if there are any plans by DAZ3D or Nvidia to work on the limitations of the current DAZ Studio Iray integration.
- - -
I think I understand what you're asking because I've been after the same thing myself.
They all do live preview. The operative word is, do. Short answer: For all practical purposes, there are going to be limits on just how "real time" your Iray preview is no matter how robust your hardware is. Iray is not a "real time" rendering option, unfortunately. Not today anyway.
The CPU first "loads" the scene into VRAM. The speed of this process will be limited by the clock speed of the CPU. The rendering per se' is done by the GPU. More GPUs = faster rendering, therefore faster preview window display.
Even the Nvidia Iray vids I've watched on YT show a certain amount of latency in screen repainting, and these people are using money-is-no-object hardware.
There's some settings that can be adjusted that let it update much faster once the initial scene is rendered, allowing me to change lights and turn the camera without going back to the untextured-rerendering wait. Instead it just goes very fuzzy for a bit, but allows for smooth lighting and camera adjustments while fuzzy. Unfortunately I adjusted those settings and can no longer clearly recall which they are, and have to run off for a few hours. If this sounds like a change you need and nobody else pops up with the adjustments I'll try to figure it out when I get back.
Go to the Window menu and open up the Draw settings window. In there under Drawing you can change the Response Threshold in msec and the Manipulation Resolution used in the window or the aux view, whichever is being used in Iray mode.
Thanks all, that's exactly what I was talking about.
I thought there was some kind of set up that let the preview NEVER pause and update.
The best I've seen is when it looks like a transition and the screen pixels out and comes back.
--
There's also a newer product in the store that is supposed have the proper settings to let slower machines use the preview mode.
I bought it, it woks, but I find it a little fiddly.
I can't find it in the store right now....
Oh, here it is....
https://www.daz3d.com/render-throttle-for-iray
-------
wow, what I want to do is impossible..
What I'd like to understand better is, just what are the circumstances in which a "reload" is called for. It seems like all the objects ought to be loaded into VRAM on the initial load of the scene.
Real Time rendering is the norm in games. I believe Unity does it.
I honestly think it's the light calculations.
I don't know about such things, but lighting/reflections/transparency seems to be the big thing that iray specializes in.
That's part of its visual magic.