some questions about creating landscapes

[PredatorPF]

Hi all,

I would like to use TG for alien landscapes, and I had something in mind...

I would like to have a deep (straight) crack that runs around the whole planet. I just don't know how to do it.

What I have tried:
A) Using a greyscale image (created in PS) with an all white image with a black line.

When using this, I have 2 problems:
1) the black color makes it "groundlevel" while white makes mountains, so no crack in the ground here.
2) When I tried to rescale it, it didn't wrap around the planet but rather went into space (like a ramp)

B) I tried to find another world creator-program (geocontrol and worldmachine) But they are not easy to use for something simple as creating a deep crack in the ground.


So, my questions are:
Whats the best method to create a crack that runs around the planet?

How can I make a greyscale image that digs into the ground? and how to wrap it around the planet

and

Is there a simple program which can be used to create landscapes (for example, the crysis worldbuilder is easy to use for creating environments)

Thanks,
Robert

[cyphyr]

Try using a simple shape shader set to negative displacement. Like this perhaps

[PredatorPF]

thanks, will look into this right now.


edit: learned something new today, thanks!

[PredatorPF]

Still have 1 question left: How can I have a heightmap that wraps around the planet? I would like to have a mountain planet with a flat part (for buildings), but the flat part is quite big, and if I use a heightmap now, I can see edges if I zoom out enough. It's tangent right now.

[Henry Blewer]

You would have to use a fractal terrain. Heightfields work best as projections (flat). The scales would have to be huge. And use coastal smoothing to flatten out the lower areas.

[Oshyan]

You could create an image map in a spherical projection and apply it in Spherical Projection mode using an Image Map Shader. A heightfield node would not be appropriate for this purpose. It is also critical that the source image be created correctly so that when wrapped around the sphere it will not distort.

- Oshyan

[PredatorPF]

When I try to use a heightfield map (even a small, normal one) it only looks good when it's located on the original rendercamera-position. On any other location it creates an heightened platform. Is this normal? (because I cannot enter 1 of the axis for position.)