Can't you still have a normal octree or something with segments of the voxels split by their spatial location with voxel subtrees inside of that? I don't understand why you can't apply spatial division techniques to voxels.
I don't think it would accomplish much. But sure, you can precompute which objects are visible in which circumstances and do some culling based on that data.
My understanding is that the problem is that there's just too much stuff that you have to keep in memory if you don't use LoD to distinguish between nearby and far away objects.
What are you going to cull? There's just too much stuff to load in memory. Too much stuff that actually ends up on your screen. Too much point cloud data. Now games use low resolution models and prerendered billboards for far away objects. With a voxel octree you're just SOL, no matter how clever your spatial optimizations.
Unless hard drives (or SSDs) become a few orders of magnitude faster I don't see how the data can be fetched from disk quickly enough.
I think you can, and I think they do; but that still doesn't solve the memory issue, actually it makes it worse since now you have to store multiple 'resolution' versions for the same data.
But if they still need to use 'traditional' techniques like LoD, rendering at various resolutions, etc, then the complexity and running speed can't be all that much faster than a traditional approach. The way I've been reading these articles is that somehow he's got a very fast method of deciding which voxels to show, without any pre-processing or optimisation - just brute force. I'm curious to see the first demo they'll come up with, especially since they only now seem to be at a point where they can render without shading, animation etc, and they make it seem as if those are just implementation details that can be added on an afternoon. We'll see.
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Can't you still have a normal octree or something with segments of the voxels split by their spatial location with voxel subtrees inside of that? I don't understand why you can't apply spatial division techniques to voxels.
I don't think it would accomplish much. But sure, you can precompute which objects are visible in which circumstances and do some culling based on that data.
My understanding is that the problem is that there's just too much stuff that you have to keep in memory if you don't use LoD to distinguish between nearby and far away objects.
Consider this screenshot from rage: http://pcmedia.ign.com/pc/image/article/116/1162072/rage-201...
What are you going to cull? There's just too much stuff to load in memory. Too much stuff that actually ends up on your screen. Too much point cloud data. Now games use low resolution models and prerendered billboards for far away objects. With a voxel octree you're just SOL, no matter how clever your spatial optimizations.
Unless hard drives (or SSDs) become a few orders of magnitude faster I don't see how the data can be fetched from disk quickly enough.
I think you can, and I think they do; but that still doesn't solve the memory issue, actually it makes it worse since now you have to store multiple 'resolution' versions for the same data.
But if they still need to use 'traditional' techniques like LoD, rendering at various resolutions, etc, then the complexity and running speed can't be all that much faster than a traditional approach. The way I've been reading these articles is that somehow he's got a very fast method of deciding which voxels to show, without any pre-processing or optimisation - just brute force. I'm curious to see the first demo they'll come up with, especially since they only now seem to be at a point where they can render without shading, animation etc, and they make it seem as if those are just implementation details that can be added on an afternoon. We'll see.