question about mask

[treddie]

Sorry for the delay in getting back.  Very busy lately.

So just because I have a high contrast preview that looks like a good mask, it's not necessarily.  It could just be altitude information?  But then I can convert that to a grayscale "bitmap" and use THAT as the mask?

But if I use a distribution shader to confine to a particular band in the terrain, why cannot that be used to tell  the displacement shader to only let displacement info through that lies in that band, and everything else is either black or pure white?  Since every point in the displacement "map" signifies precise points above the initially flat terrain surface.  Ergo, somewhere in the pipeline, those scalar displacement values are keyed to points of altitude.  No?

[Dune]

But then I can convert that to a grayscale "bitmap" and use THAT as the mask?

Yes, but that would need a render of that mask and reimport in an image map shader. You'd have to figure out the projection then.

The scond point only works if you use it in the same line to the planet input, so the main line of shaders, because that's where the band is calculated from. Not in a lake or so.

[micvswind]

But then I can convert that to a grayscale "bitmap" and use THAT as the mask?

Yes, but that would need a render of that mask and reimport in an image map shader. You'd have to figure out the projection then.

The scond point only works if you use it in the same line to the planet input, so the main line of shaders, because that's where the band is calculated from. Not in a lake or so.

here again.
i am sorry for delay to back.and this problem still trouble me.
with you guys's suggestion.and i still can't resolve my problem.displacement to scalar get a mash like image A,and i get a mask with distribute like image B.i use the mask like image C to desire a mask that offset the mask image B,but i failed.
my purpose is show like image D.maybe you guys could help me again.

[Dune]

You make it yourself too difficult. I made you a simple starting file. And, btw. a distribution shader needn't have an input for it to calculate slopes/altitudes.

And an example of what I made with this basic setup a few years ago.

[micvswind]

You make it yourself too difficult. I made you a simple starting file. And, btw. a distribution shader needn't have an input for it to calculate slopes/altitudes.

And an example of what I made with this basic setup a few years ago.

Thank you much again dune.I download you .TGD file and study it carefully.you show a way to solve the problem smartly.and i desire to get out a terrace landscape like this image bellow:
i want to offset the mask get with slopes/altitudes and displace the terrance with a scalar like -1,thus edge of every lever of the terrace is flat ,can walk people and keep water.
thank you  again.forgive me for my poor english.

regards.

[Dune]

I don't quite understand what you want, but what you show with the coloured lines - some kind of inner offset, is not possible with this setup. Not to my knowledge anyway. Maybe someone else can give you a better solution....