2D Clouds Invisible without backdrop

[WAS]

I decided to give clouds another go for rain, or snow, using a simple shape as a curtain mask. It worked fine all through testing with the black card I use to clearly see the streaks, but when I disable the backdrop the cloud layer is nearly totally invisible save for some speckling against the ground, which also doesn't even represent the noise shape. Any ideas why this is? It's a pity because it's faster than a card if you don't use glass.

These 2D hard clouds look decent for pseudo-particles too so I have tons of ideas for stuff like this so definitely wanting to get this working.

[Dune]

Hard to get it right, but it seems a little play gets it a bit better. Front cloud needs localization (and 3D). Check this out.

[WAS]

Yeah 3D defeats the purpose for optimization and speed and is huge waste of resources. Additionally, it's just filled with noise despite setting quality at 2 dramatically hitting render time. This is how I always have set it up and it's not practical and a waste of time. The method here is super fast, and clean. But for some reason 2D clouds don't seem to be working like they used to?? I've done projections of cloud masks onto 2D clouds for fake cumulus and it used to work in TG 2 before I knew how to do anything with scalars.

The point here is WHY isn't 2D working as it should, and just being invisible in a situation it should be visible (against the sky; or even distant terrain).

[Dune]

It's maybe that 2D clouds are projected on a flat plane XZ. I don't know otherwise.

[WAS]

Hmm. I'm not sure. That doesn't seem to be something that would affect the sampling with a backdrop or not. Also is it XZ? It still applies depth which would by on Y.

[Dune]

I always thought high clouds like cirrus can be done in 2D because they're on a flat XZ plane (Y height=0, or perhaps on a big sphere), so I wouldn't know how that would look when lowered to camera height. 2D is flat, so no depth I can imagine, other than in color.

[WAS]

Yeah I think you're right. it's just projected onto the XZ plane, wherever it decides. But why a backdrop makes it visible is interesting. Would be nice to be able to have XY/ZY modes.

Well oh well. Too bad v2 is still really slow trying to do tight small shapes.

I did a few tests with a huge depth cloud into the planet and sky, and it would project only into the sky, unless a backdrop was applied again. Really strange. Really wanna know what that is. Lol