Why My Iray Render is Different from my Iray in Viewport?

James

In the viewport everything looks good.

But once rendered the some cloth sticking out/intersecting with another cloth...

How to fix this difference?

crosswind

It happens from time to time...AFAIK, the mechanism of handling smoothing/collision with Draw Style - NVIDIA Iray preview in Viewport is different from the final rendering... You may try to switch options in Instancing Optimization or give more smoothing iterations / collision values, or tweak values of the relevant morph dials on the garments... if there's any 

PerttiA

Pokethrough happens often because the viewport SubD is lower than the one used in rendering.

Dartanbeck

PerttiA said:

Pokethrough happens often because the viewport SubD is lower than the one used in rendering.

If this is the case, select the garment (or whatever) and look in Parameters: General > Mesh Resolution. Make sure that rendering resolution is equal to or higher than viewport

James

@Dartanbeck

How to make sure that?
Which dial to change in general > mesh resolution?

Dartanbeck

Yes. In Mesh Resolution, you can have Base resolution (no SubD) of High Resolution, which is adjusted with values below.

SubDivision Level controls how much smoothing is applied in the viewport (working view)

Render SubD (minimum) controls how much smoothing is applied during the render.

 

If the Render SubD level is a lower value that ther SubDivision Level, then you're seeing more smoothing in the viewport than in the render. I've never actually tied that. Niot sure it's possible. Why? I suppose there can be reasons for anything though.

I doubt this is it. I just have a feeling that the lower level viewport Iray isn't showing it because it's a matter of close proximity to the point where it doesn't reveal itself until the engine can really dig into those shaders vs light, etc.,

 

For me, I've always used Fit Control products to help with that. In animations that tool really comes in handy.

I just got the complete Mesh Grabber Bundle, and that thing is incredible! It's like being able to build your own Fit Control morphs on the fly - so using it with Fit Control is really a blast.