Fractal terrain causing vertical jumps??

Started by gpstevens61, May 17, 2009, 11:33:53 am

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gpstevens61

I'm using the Fractal terrain to provide the general topology of the scene but it adds in areas where the surface jumps by 200-400m instantly, making it look like an artificial cliff.  I've got the following settings:  feature scale 1400, Lead-octaves 1, Smallest scale 10, Noise octaves 6, Displacement is applied with amplitude 2000, offset 0, roughness 1, there is no shader set for blending.  The other settings are Scale step 3, stretch factor 3, Late deposition 0.06125, Early deposition 0.25, Early deposition rate 2, Warp amount 0.25.

Any explanations, suggestions gratefully received.

Mohawk20

Just reading this quickly, I'd say it has something to do with the scale and displacement. For a hill like landscape with no cliffs, displacement amplitude should not be higher than the fractal scale.

If you play with those settings you might find a result you like.
Howgh!

Oshyan

It would also help to post a TGD and/or example image so we can really see what's going on.

- Oshyan

cyphyr

May 19, 2009, 11:11:13 am #3 Last Edit: May 19, 2009, 11:52:42 am by cyphyr
The only way I could see a simple fractal terrain doing this (NOT Alpine Fractal) is if, under the tweaks tab, you have some quite large nunmbers in the "Noise variation", "Boyancy from varaition" and "Clumping of varaition". A post of the tgd would help :)
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Matt

There is a bug in the Alpine Fractal which causes discontinuities like this sometimes. I haven't been able to fix it yet.

Matt
Just because milk is white doesn't mean that clouds are made of milk.

gpstevens61

Here is an example,  thanks

The settings are different but the effect is the same.  One thing I've discovered is that if I change the feature scale by a small amount (say 10) the "cliff" moves across the terrain.

Oshyan

This sounds like it may be an example of the bug Matt is referring to.

- Oshyan

gpstevens61

That's OK, at least I won't spend any more hours tweaking random settings to try and get rid of it.

Thanks