LOD you mean Level of Detail. Havent work with LOD before, so I will spend some time research it. So now you mention HeightMap, and I saw many ppl use it for terrain. I will try to make a demo with heightmap. I hope I can get the result I want. I'll post the result right after I finish it . Thanks .
FurtherMore, in the note of the game Development Diary. They say the use "Soft filtering and noise for terrain lighting ', but I don't really understand what it means. This is a specific technique ?