displacement map or heightmap

No one knows?

I would say displacement map. But that imho based on how much i heard of displacement map and heightmap mentioned by 3D programmers. And as i understood displacement map gives better results.

You can find a lot of info on that (and examples) from Nvidia developers web page (thats if u using HLSL) http://developer.nvidia.com/page/home.html. Then there is directX documentation i think got some stuff on that from programming point of view and of coz there is tons of books.

Do you understand what the two techniques you mentioned are? They are both independent and compatible. In a sense, a heightmap acts on vertices in the same way a displacement map acts on pixels. Their implementations are very different, but the two could be used together to create, respectively, macro and micro details on the terrain.

I could find you plenty of terrain examples that use a heightmap with no displacement map, but none the other way around. Perhaps you could describe what it is that you're trying to achieve so we can direct you more accurately.

Admial

In my graduation design, i wrote a demo about LOD terrain. For triangle splitting, i just read some article from gamedev and gamasutra and implement it myself. To ease terrain popping, i copy the raw heightmap data to a new working height buffer, and when splitting or merge are needed, just lerp between them.
For demonstrations need, i draw a robot on top of the terrain and implement shadow volume on it.

Now im just graduated and got a job in a game developping company besides our school. I think i can expand my research in the college. First the size of my terrain demo is limited, if i want to simulate the real world, some advanced resource management methods are need. Second, my terrain vertices dont contain normal data, so it doesnt look that real. But how to compute normal for a random splitted terrain, i failed to find any article about it.

And i haven`t try anything about indoor scene management, so links are welcome.:) And maybe some method to transform between indoor and outdoor scene scene are interesting. And I love water effect, In my dream, i want to build a game under the sea named "Water World" :), then i eaven read about physics--hydrokinetics.

Now, please give me some advice to improve myself, thanks.