Altitude dependent?

[cbalaskas]

Is there a way to have an effect be altitude dependent? For example, for a voronoi pattern to increase in scale as the altitude increases? Been messing around with functions for a while, but I can't seem to wrap my head around it.

[mrwho]

well, I think you could use a very specific image mask, and tie that into the equation somehow, but I really don't know. good question

[sonshine777]

You could try creating a different scale pattern for each altitude range and runnig each through a surface or distribution shader to set the altitude. I know it the long way around but all I can think of at the moment.  

[cbalaskas]

Yeah I had had that idea for a minute, but wouldn't it be great if it was the same noise pattern increasing smoothly. Er, maybe that would look like crap now that I think of it?

[Oshyan]

Perhaps there is some way to feed a "get altitude" into the scale, possibly passing through some other number crunching along the way? I'm afraid I'm not an expert on the function nodes.

- Oshyan

[mogn]

Convert altitude to range 0..1:  abs(alt)/(1+abs(alt))
Plug this into a mix scalar with e.g a constant 50 int one input and e.g 500 in the other output, and the converted altitude into the controller tab.
The output of this is put into the scale tab of the noise function.

[mogn]

I realize that the conversion of the altitude, in the tgc I sent, is mush to dense towards zero.
If you know something about the lowest an highest altitudes in the image, a much nicer distribution
can be found.

[cbalaskas]

Ok, so me being right-brained and looking at this, I think you mean I have to know the altitudes to feed in in order for this to work? SO on a power fractal, what would those values be? I would guess whatever the dispalcement is (if 1000, then values -500 to 500)?

[cbalaskas]

Well I threw in a voronoi noise in where you had the perlin and rendered. Something interesting is happening, it seems the y scale of the pattern is getting squished relative to an increase in altitude. Could be useful, but what I'm after is small on the low altitudes and a larger pattern at high altitudes, with out squishing or stretching if that's possible.

I'll use this and drive the "cracked Face" displacement and post the results. Thanks for your efforts!

[cbalaskas]

Bizzaro land!  Interesting. I'm going to fiddle around and see what I can come up with.