GPU Geoclipmap screenshots

Solid mode:

This is Mars

Wire frame:

Grids across 2 faces

Grids across 3 faces

These are the screenshots of my geoclipmap demo.
The algorithm is based on the rectangle geoclipmap [paper link]
The grid of the sphere is indeed a grid cube, which composes of 6 rectangle geoclipmap patches, and the grid cube is then projected into sphere.
The inter-plane cracks are eliminated by my own algorithm. It is quite simple, but it works quite well.
The heightmap sampling and the sphere projection are all done on GPU. Therefore it requires a SM4.0+ GPU to run it.
The shading of the terrain is just a simple height to color mapping. I'm going to implement a more sophisticated shading scheme later. My current focus is to get the partial texture update working, which requires some modifications on Ogre3D.