I've been experimenting a lot with creating mountains using isosurfaces, but
I can't seem to quite get it right.

I've been using a paraboloid function as the basic shape (x^2+y+z^2). I have
been trying to use pattern noise to carve out parts to make it look more
like a real mountain. I've mainly been using crackle and agate, since they
seem the closest to what I want.

The problem is that when I make the noise large enough (either by scaling
the #declared pigment function in the declaration, or by increasing the
multiplier at the end of subtracting it from the base function, or both),
it always leaves "floaters"... pieces of terrain that are not actually
connected or are connected by very thin sections to the main object. If I
make the noise small enough to prevent this from being noticeable, the
general silhouette of the mountain is still a perfect paraboloid and looks
very unnatural.

The bottom of the mountain doesn't matter at all because I have a fog layer
acting as low-flying clouds that completely obscure the lower elevations.

I think the problem is finding a good medium between the scaling of the
whole isosurface and the scaling of the noise. Right now I am using the
following measurements:

the base function: (x*x)/5000 + y/90 + (z*z)/5000
the pigment function: there are two, actually. One is crackle scale 50 and
the other is agate scale 5. Both are subtractive (meaning I use "+") from
the base shape.
contained_by: a box, with -500,500 as measurements.

Now, I have seen some great isosurface work before (particularly I remember
an entry in the Asia IRTC that had photorealistic terrain entirely made
with isosurfaces)... Anyone have an suggestions on what I could do? Thanks.

-Justin Smith

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