Limit of terrain rendering with Projected Grid

For fun purpose, I’m developping my own graphical engine based on OpenGL ES 2.0 on Android.

I want to integrate an “infinity” terrain procedural rendering. There is a lot of possibilities, I don’t know where to start, I think about :

Anyone have worked with projected grid for terrain/water ? Is there limitations ? (volume shadow, integration with physics (Bullet))

Finaly, is there a better technic than projected grid ? (I need LOD, less CPU, more GPU)

Thank you very much and sorry for my poor english :wink: