Which Terrain?

#21 @Dave: I believe Tom mentioned some speed improvements in an upcoming legacy patch in another thread. Currently though Atlas gives far better performance on my system. A 2048x2048x1.5 square sized Atlas map for me will get about 435 fps with a view distance of 5000, where a 512x512x4 square sized legacy will get only around 120 with a view distance of 2500, if you can see all four squares. Splitting that into smaller squares and using a paging system would probably make a big difference, as the performance does improve significantly if you don't see the other squares. This is prior to whatever speed improvements are going in for it. But as it stands now the performance difference is significant. The cost of it of course being that you can't edit at all in realtime in Atlas. I do think that it still serves its purpose, depending on what your trying to do. Personally, I'm sticking with Atlas. The majority of users seem to be going in the other direction though and with the new terrain.

#22 @Dave

Quote:1) If the new mega terrain does all this stuff does that mean Atlas2 is effectively dead?

Not at all. Its great if you need massive amounts of high detailed, high performance, paging terrain. It just has the downside of larger data files and longer turn around time in editing.

@JC
TerrainBlock is painfully slow because it was designed for the original generation of 3d acceleration. When 3D cards just did rasterization and you wanted to process the fewest triangles possible. In the end TerrainBlock on each frame packs up individual triangles into a dynamic vertex buffer and sends them off to the card to be rendered. The process of selecting and packing the triangles is extremely CPU intensive.

The 'patch' i'm working on goes about it using the realities of modern 3D cards. Modern cards love triangles... tons of triangles in huge batches. The GForce 7 series of cards can process more than 7 million triangles per frame at 30fps. It is extremely rare to find a game to be triangle bound... its always fillrate or draw calls.

With this in mind my change keeps things simple. All the geometry is packed in the biggest possible static vertex buffers and we do no geometric LOD. This works surprisingly well... you remove all the CPU overhead and put the work squarely on the back of the card.

I'll post more as i get the changes merged in and tune up the clipmap code.

#23 JC and Tom, thank you both very much. Very useful info, I'll keep an eye out for that patch. I guess it will appear in the next Beta?

Best,

Dave.

#24 @Dave - I don't think it will be in the next beta... but it will be out sometime after that.

#25 I still haven't worked much with terrains but this thread is quite interesting. As I read everything above,
Tom , i would like to hear your opinion about this. If making the game to run on Xbox360 it's better to use Atlas/Atlas2?Is this right?

#26 OK thanks Tom.

#27 @Picasso - I don't think there are any hard and fast rules. As of this time i don't think Atlas has been shipped in a game on the 360, but TerrainBlock has (at least in ThinkTanks). Both should work fine... i would choose based on your needs.

#28 I see, Thanks ,Tom