Smoothing Iterations and Collision Iterations doesn't work when rendering?
handel_035c4ce6
Posts: 482
in The Commons
I am trying to fit a G2M shorts to G3M figure and almost succeeded - couple of small imperfections remained. Following a tutorial I increased Collision Interations and Smoothing Iterations values a little bit until the imperfections were covered. But when I made a spot rendering the imperfections appeared again on the render.
Any advice please?
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Comments
I'm seeing that too sometimes.
I get this too. I'm starting to wonder if maybe having the subdivision levels set the same for the viewport as well as render would have any effect, though I've not tested this to see. That's the only thing that I know of that change between the meshes or whatever from the viewport to the render that might cause this issue to occur. Of course it's just a guess and I could be totally off with it. Might be worth looking into, just match the veiw subdivision to the render one uder the parameters tab
Thanks. Will look to this tommorow (I remmember the Subdivision level of the pants was at 1, but didn't look at the rendering SubD level).
Edit: Nah... the SubD levels were the same (1). Changing them to 2 changed nothing. Raising both the smoothing iterations and collision iterations to levels 100 and 50 still left some imperfections and basically this shouldn't be the way to handle such problem. And besides this rasing the collision iteractions increases the rendering time a lot.
That sucks. When I've had this happen to me I've always wondered where things change between viewport and final render. Even in the iray previews stuff looks fine but once you hit the actual render button things get all whacky. There's gotta be something else that is different between the two.
I've been running into this too. I've had to use fir control and poke-away to get rid of them. or scailing parts of the clothes a little. :(
I suspect the reason this is happening is that the G3M figure you are using has some displacement or normal maps that are pushing the skin through the clothing at render time. Whilst smoothing results can be seen in the viewport, the normal/displacement effects are not. You can try to turn these off temporarily in the surface settings to see if this is causing the issue.
If so, and you still want to use the displacement maps, try creating a geo shell, and fit the clothing to that, applying an appropriate size to push the shell out to fix the poke through. If you have Zev0’s fit control for G3M this can also help you.
I'll have to take a look, but I wasn't aware I was using any displacement on my figures (let alone enough to cause so many issues with smoothing)
But I'll have to look, just to be sure whatever material options I chose didn't have this setting in it already.
Scaling up several percents helps but if for the spot rendering ~105% were enough, the final rendering needed 112% for me.
Could it be the difference between 'Iray Interactive' and 'Iray Realtime'?
I switched to 3Delight render and there wasn't a problem at all. So it is definitely due to lray <-> Daz interactions. Could be because G2 is relatively old the problem to be Iray shaders related?
That's most certainly displacement issues, the trick is to set the min displacement value(for the clothing) to 0 or even a positive number, maybe also increase the max value a bit. Also check the skin displacement and do teh opposite way if needed. Oh and don't set the smoothing and collision values to the same number, avoid setting collision to a multiple of the smoothing value. For example if smoothing is 3, then collision could be 2, 5, 7, 10 and so on;)
Also try toggling between base shape and generic if nothing else helps.
Here is another forum discussion on the topic; I didn't realize shaders had displacement values as well.
https://www.daz3d.com/forums/discussion/92291/secrets-of-poke-through-smoothing-collision-detection
In Blender some artists are creating real 3D displacement maps for more realistic renders. This increases the polygon count but as those 3D dispalcement maps are ratively low poly maps they don't add a lot. Do you mean Daz can use there similar displacement maps too? Or is the "displacement value of a shader" something totally different?
Edit: https://www.daz3d.com/forums/discussion/92291/secrets-of-poke-through-smoothing-collision-detection
The Push Modifier from here worked nicely.