multiple Distance Shaders into one Cloud Node?

[kentm]

Hello,

A question about Distance Shader usage. To cut holes into cloud layers - can more than one Distance shader feed into one Cloud Node, in order to control the shape of the 'cut'?

Thanks,
Kent

EDIT: I think probably not, and I understand that the better way is to build up a cloudscape using a series of smaller "banks" if I want a specific look, I'm just wondering if there is a way to feed more than one in.

[WAS]

Hello,

A question about Distance Shader usage. To cut holes into cloud layers - can more than one Distance shader feed into one Cloud Node, in order to control the shape of the 'cut'?

Thanks,
Kent

EDIT: I think probably not, and I understand that the better way is to build up a cloudscape using a series of smaller "banks" if I want a specific look, I'm just wondering if there is a way to feed more than one in.

Maybe you could explain what exactly you're trying to explain. By what you're saying "cut" and shapes, it'd seem more practical to use the Simple Shape Shader.

[Dune]

I just had an assignment where one wanted clouds over specific parts of a terrain, and I used simple shapes to mask different cloud fractals, all added with an 'add color' (blue node). This way every area can be reseeded/adjusted by its own.
Distance shader can work too, but if set to (default) spherical, the distance will be restricted in Y too. Not so with simple shapes. Different distance shaders (each with thei own camera) can be added, subtracted, multiplied.....

[Oshyan]

Yes, you can use multiple distance shaders, you just need to merge the results appropriately before feeding it into your cloud layer.

- Oshyan

[kentm]

Thanks for the feedback, these will give me something to work with for a bit.

Oshyan - what is the appropriate node to use to merge the distance shaders?

WASasquatch - thanks, I'll look into the simple shape shader. I'm trying to find the best way to control where I place the clouds into the sky and where there are no clouds. My background is in matte painting so I tend to want very specific 'looks' to the skies. I love the happy accident technique, of which terragen is giving me so many good options, but I'm trying to learn the best ways to control the 'layout' Just digging in... 

Thanks again.
K

[cyphyr]

If you want to make a hole in a cloud layer (that the sun can shine through or you can see sky beyond) try using two Simple Shape Shaders. One massive one covering the whole visible sky (say 100000 xx 100000 or more maybe) and make it white and below that have another smaller Simple Shape Shader only this time make it black. Then plug this into the Cloud Fractal Shader "Mask by Shader" input.
This will allow cloud to be in all the white areas (at what ever density and coverage you have set in the Cloud Fractal Shaders density tab) but not in the black area of the SImple Shape Shader.
You can have multiple Black Simple shape Shaders and place them where you like.
Add a Fractal Warp shader to give the holes a more natural edge.

[Oshyan]

To merge multiple Distance Shaders (or any other shaders with color/displacement), just use a Merge Shader. You don't need to use a Mix Controller if you just want a simple blend. Adjust the blending options and ratio to get the result you want, e.g. subtract one from the other, etc.

- Oshyan

[D.A. Bentley (SuddenPlanet)]

It's kind of related, so it might be useful to check out the threads that pop up when searching for "Donut Distance Shader" and "Doughnut Distance Shader"

Here are a few:

https://planetside.co.uk/forums/index.php/topic,4390.msg46188.html#msg46188
https://planetside.co.uk/forums/index.php/topic,15584.msg151455.html#msg151455
https://planetside.co.uk/forums/index.php/topic,25445.msg253815.html#msg253815

-Derek

[kentm]

Awesome. Thanks very much folks!

[Dune]

@ Richard; why using a huge white and small black simple shape when you can inversely mask by a small white SSS? Or use a constant (white) color (blue node) followed by a small black SSS.

[cyphyr]

Yes that works (just tested it)
Hmmm I remember trying just that a couple of years back and I just couldn't get it to work.
Terragen improvements of my slightly senior brain fuzz (probably the latter)

[kentm]

cypher, thanks again for suggesting the two Simple Shape Shaders. I just set it up to have one small shape cut a hole out of the larger one, combining them with a merge node and running it into the Mask Shader. I used two white (positive) colors and set the merge to subtract the input from the shape I wanted to "cut". cheers.

[WAS]

cypher, thanks again for suggesting the two Simple Shape Shaders. I just set it up to have one small shape cut a hole out of the larger one, combining them with a merge node and running it into the Mask Shader. I used two white (positive) colors and set the merge to subtract the input from the shape I wanted to "cut". cheers.

You can also achieve this by simply doing one Simple Shape Shader as Ulco stated, at the desired size for your hole, and apply it to your Mask By Shader and check Invert Mask. Less computation of SSS shapes. The PF will than render in finite detail except your SSS circle.

[kentm]

ah, got it!

[cyphyr]

@ Richard; why using a huge white and small black simple shape when you can inversely mask by a small white SSS? Or use a constant (white) color (blue node) followed by a small black SSS.

Realised what I was thinking (at last).

The "Easy cloud" set-up will not allow masking to be inverted (feature request please!) hence the need for the sky covering huge white SSS with smaller black SSS allowing gaps for the sun to shine through.

Only realised because I tried using Easy Clouds again today.