melt snow on one side of a mountian

[Grassynoel]

Hi All.
How would you suggest I build a flow to melt the snow on just one side of a mountain? I can't seem to work out how to mask by direction.

Thanks
~Glenn

[Dune]

Use a get normal in texture function, rotate X or Z and input in distribution shader. I cut this screendump off a little too much, but at the bottom there's a distri shader.

[reck]

Ulco, how do you know to do that?

Is there any way to "work it out" or any documentation or does it just come down to understanding maths? I get lost on a lot of the blue node work and I sometimes wonder how users know how to do certain things with them.

[Dune]

Experimentation and a little logical thinking helps a lot. I try a lot of things and see what happens.

[Grassynoel]

Thank you.
Likewise I would have NEVER worked that out.  In world machine angle is as available as slope or altitude. I think it deserves to be exposed as a basic option.

~Glenn