Re: [Algorithms] Terrain performance comparrisons

[Trent P. <tr...@po...>]

I'm personally in the Chunked-LOD camp myself. It's flexible,
easy-to-implement and speedy. The only problem I can foresee with the
algorithm is that I think using a dynamic dataset (ala TreadMarks) may not
be feasible. I haven't played around with it much myself, so there's not
much to back that statement up with other than mere speculation. I think it
would be possible to use a dynamic dataset, but it would probably require a
rather heavily modified implementation of the algorithm. This is though, as
I said, mere speculation.

As for teaching/learning the Chunked-LOD theory and implementation, I tend
to use the "stepping stone" method. Basically, I tell people to learn the
basics of Geomipmapping (the algoirithm is pretty basic by nature), code a
sample implementation, and just mess around with the code a bit to see the
pros and cons of the algorithm. Once someone has done that, learning, and
implementating for that matter, Chunked-LOD tends to be a lot easier.

Of course, it's important to note that Geomipmapping is simply not a real
competitor for "best modern terrain algorithm", simply because it lacks a
lot of the optimizations that Chunked-LOD does. I personally consider
Chunked-LOD an evolution of Geomipmapping. They're very similar in many
ways, but the former takes many more steps that increase the overall
performance of an implementation.

However, with all that said, Lucas definately brings up some very valid
points. The ROAM 2.0 algorithm, from what I've seen, produces really
incredible results. It's flexible, speedy, and less memory-intensive than
Chunked-LOD; not to mention the fact that the scalability of an
implementation is amazing. On one of my simple implementations, I can zoom
from "way out" in 3D space to a "nose-to-the-ground" view without so much as
a studder in performance. Though, on the whole, I think ROAM 2.0 is a much
more complex (code-wise) system than Chunked-LOD, and it really requires you
to do your homework.

Both of these algorithms produce top-notch results. In the end, however, it
really depends on which of the two you feel best suits your game. *shrug*
---
Trent Polack
tr...@po...
www.polycat.net