Help with shaders

Started by NuttyMonk, May 11, 2007, 05:09:45 pm

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NuttyMonk

Hi all,

i know this might actually be quite a simple problem to fix but i need some help.

You can see on the pic below that i have a mountain in the background and smaller hills in the foreground.  I've taken most of the shaders off but you can see the brown area which only goes up to approx 1,000m.  The area in the red rectangle is the problem.  The shader gives quite a sharp line between brown and grey.  If i increase the 'fuzzy zone' on the altitude constraints i still get a horizontal line but it isn't as sharp.  I've been trying to use a large scale 'power fractal' in conjunction with a 'distribution shader to make the line between the rock and mud more sharp and jaggy.  Below is the setup i am using.

The large scale 'power fractal' goes into a distribution shader which then goes into the normal power fractal for the mud layer.  I've tried rearranging things but can't get the effect i want for this to look more natural and less artificial.

I want an area around 500m to 1k to have a different fractal breakup from the stuff below 500m.  Does anyone have any ideas how i can do that and get a more jaggy natural look to the mud layer where it merges with the rock layer?

rcallicotte

One way I've found, and likely not the only way or even the best way, is to combine the Altitude Max or Min with the Slope Max or Min.
So this is Disney World.  Can we live here?

bigben

Try taking it back a bit...

Your basic shader comes with a fractal breakup.  Set the altitude and height constraints in the shader and increase the fractal breakup amount above the default 0.5...  This will increase the fractal breakup of the "fuzzy" zone

rcallicotte

This is a good idea, Ben.  But, do you mean "increase" by giving more breakup by setting it lower, like .005?


Quote from: bigben on May 11, 2007, 10:35:46 pm
Try taking it back a bit...

Your basic shader comes with a fractal breakup.  Set the altitude and height constraints in the shader and increase the fractal breakup amount above the default 0.5...  This will increase the fractal breakup of the "fuzzy" zone
So this is Disney World.  Can we live here?

NuttyMonk

Hi,

thanks for your suggestions.

I've managed to get a better transition now between the rock and the earth layers but it meant creating another couple of earth layers underneath the original one and giving them progressively less coverage and increased fractal breakup as they moved toward the rock layers.  It's still not quite how i wanted it but i think i might try using the voronoi fractal noise node to see what happens.

Cheers again for your suggestions.

bigben

Quote from: calico on May 12, 2007, 11:17:08 am
This is a good idea, Ben.  But, do you mean "increase" by giving more breakup by setting it lower, like .005?



No, I mean increasing it to 1 or even higher.  It's a trade off because as you go higher the contrast in the blurred zone increases.  You could also tweak the scale of the fractal to provide a coarser breakup as well.

rcallicotte

Ben, I've never experimented with that thinking that a lower fractal number is always better to overcome a stiff look to the terrain.  I guess it's time to learn something.  Thanks.
So this is Disney World.  Can we live here?