Hi Matt,
Linda placed the displacement after the compute terrain, and I thought that would be the trouble, and re-ordered the nodes, so that all happens before the compute terrain.
Linda's scene works in the following way. She takes a simple procedural terrain. Then based on a min altitude, she adds another power fractal with an offset displacement, which creates the mushroom shape.
However, the cracks that you see are no cracks. There is no other significant displacement function other than the power fractal that displaces with an offset, with a min altitude constraint.
There are 2 issues:
1 - If I put everything before the compute terrain, the mushroom won't appear, because the renderer seems to think that the terrain is still a perfect sphere, with normals facing away from the center of the planet.
2 - If I create the fractal terrain, add compute terrain 1, then add a distribution shader with the altitude constraint and the mushroom powerfractal child, then compute terrain 2, I will get the mushroom shape, but TG2 will not render large patches of the terrain correctly anymore. This is waht makes these cracks. If you get the camera closer to these cracks, the renderer starts choking and will progress very slowly, with black patch areas.
I've attached the tgd and how I re-ordered the terrain.
Regards;
Frank
