How to add displacement on edges

[Olivernov]

Hi,

I want to add displacement only on the edges of a mesh. I have tried a CoronaMix ( Top: noise map, Bottom: empty and Mix, either CoronaAO, curvature or RounEdges) . Nothing is working. Looks like the AO, curvature or RoundEdges could not be used as mask in the displacement channel. The other channel support it.

Did you try to achieve that ?

Maybe it is a feature request ?

Thank you !

[Juraj]

No sadly they cannot, because the order of operations is opposite. Displacement happens first.

You have to use some permanent masks, like Vertex paint, Data Channels, baked-in AO.

Trust me, I was looking for perfect procedural render-time solution for edge displacement for AGES. Nothing is really suitable well yet.

[Olivernov]

Hi,
Thank you for your reply !

Ok I see, Corona is calculating the AO and Curvature above the displaced geometry.

That's really clear ! It looks like there is no workaround ? Actually I though there was something working with the CoronaroundedEdges in "Fast Mode" have you tried ?
So hopefully that could be a request for a next release ? That's really something missing in corona, if you want to push more..

thank you !

[Juraj]

Yeah I used RoundEdges few times, but it is very very problematic. Sometimes it works, sometimes not, each mode interacts differently with different geometry.
It had 50 perc. chance producing viable mask, and 50perc. chance producing ugly artifact. It was too much of workaround.

I sadly don't have time now but I would post the setup and examples where I did that. But I don't suggest going this road, I abandoned it.

[romullus]

If you really really need it and it must be procedural, then you can try data channel approach, but as Juraj already said, it's finicky to setup. https://forum.corona-renderer.com/index.php?topic=2466.msg205081#msg205081