Volumetric/SSS rendering "Clouds"

[TomG]

The CoronaVolumeMtl, with Inside mode, and noise connected to a distance map should work well, as in the image below - this was Ludvik's set up if I recall. There is a plane just outside the top of the cube, and the distance map uses that as the Distance From object.

To get the hang of the CoronaVolumeMtl there are some sample scenes on https://corona-renderer.com/resources/models, including a ground fog scene (other than that, no clouds though - but the samples will give you the idea on how the Inside Volume mode works!)

[nockain]

I downloaded the file from the disney site again, unzipped them and when I tried to load I still had the same problem.
Try loading another file from the site, the rabbit in cloud form that is smaller, and does not load.

Tom G, cecofuli, and the rest of users, thank a lot. If you have any other idea. For the moment we are more concerned that our function does not work well, corona volumegrid. ???

[TomG]

Which Corona version are you using? I am on the latest daily build of Corona 3 at the moment, though was opening and rendering things like the rabbit cloud with Corona 2, so quite odd that they won't load for you.

[nockain]

Tom, thanks for the help. we already corrected the versions, and also
we send you the photos following your example. Something we are missing along the way.

[cecofuli]

Tom, the Ludvik's setup "works", but it's not possible to use it in production, because it's slow like the hell!!!
Try to render a single frame in FullHD or in 4K...  =) It remember me the "speed" of the first Maxwell renderer ^__^

[nockain]

Finally I supposed to the Ludvik test works with some build that we do not have. maybe the version of max 2017 mine, 2019, the test, it is strange that both tests look very similar and in the render does not come close.

Thank you so much guys. But I do not think that this crown even have it resolved at least for the official version that we have.

[cecofuli]

You are using 3ds Max 2017 + Corona 2.0 and it works. I think you are doing some errors in your setup. =)

[pokoy]

Maybe scene units are different and the effect is to faint to be visible?

[TomG]

On it being slow, that may just be inevitable with the amount of calculations that happen in it - also in this case the user said they didn't care about speed, they just wanted the effect working :)

For nockain, I would start without any noise in the CoronaVolumeMtl, and adjust the settings until you get an evenly cloudy cube - volumetric effects are always scene scale dependent and you need to adjust absorption distance to get the desired result, which could be 1cm or 10cm or 1m depending on the size of the objects, scale of the scene, etc. (In my test scene, the cube is very large indeed, and this looks like a much smaller scale).

Once you have the "plain" version working, you could add some noise and distance map back in - again bearing in mind the scale of the noise will need to be matched to the scale of the scene, and the distances in the Distance Map will also need to match the scale of the scene. Hope this helps!