Implemented a new approach for grass rendering into IceX3 editor. It's based on the shader method Superku mentioned some pages ago in this thread. I also added smooth fading out, better shading and color correction. Works incredibly fast.

The shader works like this:
- the grass is placed by vertex shader from a heightmap of the terrain
- the shading of the grass ignores self shadow gouraud shading. Instead the exact shading as the terrain is used, based on a normal map which was generated out of the terrains normals.
- the grass color is lerped into the color of the terrain texture beneath the grass. For this a diffuse texture is used, which was generated out of the terrains texture.