Is Unlimited Detail real?

Question

Many aspects of Unlimited Details Unlimited Detail Technology seems dubious to me, even the introductory paragraph (because of the usage of the word unlimited):

Unlimited Detail is a new technology for making realtime 3D graphics. Unlimited Detail is different from existing 3D graphics systems because it can process unlimited point cloud data in real time, giving the highest level of geometry ever seen.

The quote above is from the Unlimited Detail Technology Site

My question is: Does this unlimited detail technology actually exist? And if it does, why isn't it currently being used in games?

Other references to the Unlimited Detail Technology:

• Article on Rock Paper Shotgun
• A video demonstration on Game Trailers.com
• An interview With The Creator (Bruce Dell)
• Article on Download Squad

Update

Unlimited Detail recently released a new YouTube video. I'm not any more convinced. I wrote a blog post about it, as did Notch (he thinks it's a scam).

Answer 1

Does this unlimited detail technology actually exist?

It has for decades, although it's normally called voxels. A few games used voxels back in the 90's, most notably Commanche and Outcast. The terrain in both games looked amazing at the time compared to other stuff out there. Looking at the videos the "advances" with his system, seems mainly in handling the sheer number of points. So it's faster voxels but hardly some new unlimited technique.

And if it does, why isn't it currently being used in games?

Like all techniques it has it's strengths and weaknesses.

You don't see many animations being shown since that's not a strength of voxels. At a brute force level you've got to store the offset positions for every point in the object per frame of animation, which is really ugly from a memory standpoint vs. a skeleton and rigging data in traditional poly rendering. I'm sure there are better solutions, but it's a weakness for voxels.

There are other issues, shadows can have some creepy artifacts and voxel tend to look a lot uglier when you get to close to them than polys do, although in theory if you've got enough voxels you won't notice.

Answer 2

Yes it is real,

It really can render things at any detail density without slowing down.

But it does have some notable restrictions.

• The environment is static. No dynamic lights, animations, or shaders.

• All objects are data heavy both in memory and in storage.

• The amount of unique objects is limited by the amount of memory and storage that the user has.

• Character animation would either have to be standard polygon, use some kind of sparse-voxel character animation technique(computationally heavy), or load a different model for each frame of animation.

With those restrictions a large amount of game types would not be possible. But there are game types that already have static environments that could work well with this technology.

Most likely developers who use this tech will use a hybrid approach of Point Cloud rendering for static environments, and high resolution polygon rasterization on the GPU for character and other dynamic objects.

Answer 3

It has always looked like sparse voxel octrees, to me. If my guess is correct then it's real, but limited. Namely, you can't really do animation with sparse voxel octrees, so this trick is only useful for static geometry.

Answer 4

Current hardware supports an evolution of the kind of graphics that appeared in the 16 bit days - arguably even the 8 bit days. A completely different approach may not be a bad idea, but there already are alternative approaches - ray-tracing and voxel-based, at least.

"Unlimited detail" sounds to me like the old fractal-compression fallacy. Fractal compression can represent any image, but with compression ratios not so different from JPEG.

At one point, there were claims of massive compression ratios - but the logic for that was the same as for "vector graphics compression". A single rectangle is a very simple shape to represent in vector graphics, giving an impressive compression ratio, but it's a special case that isn't useful for encoding a typical photo. The same applies to the old fractal compression fallacy. A single simple fractal may have a tiny encoding using fractal compression, but that's hardly a miracle of compression.

Another answer has already associated point-clouds with voxels. The only way I can image "unlimited detail" being justified is if there's some repeating-patterns and/or fractal aspect to those point-clouds, and some of those example images seem to suggest that too. Otherwise you'd need infinite data to represent that unlimited detail.

A fractal arguably gives an infinite level of detail. Theoretically, that is - discrete rendering automatically implies a finite cutoff to that detail, and that applies to voxels as well as pixels. However, you can't easily represent anything you want in that fractal form - it may be possible to define arbitrary point-clouds, but you'll need complex point-cloud descriptions to get the forms that aren't so naturally described as a single simple fractal.

None of this means the idea isn't interesting or useful. It's just a kind of "beware of the marketing claims" thing. And just because something looks good now, doesn't mean it won't be "just another tediously obvious point-cloud effect" in five years time.

Answer 5

IMO, it's a hoax at best, and a scam at worst.

Don't believe it until you have got a demo so you can verify the "extraordinary" claims for yourself, or at least until any industry experts vouch for it (John Carmack, Epic Games etc).

Notice the claim on the site that it's being released in "16 months" from now, since they haven't set a definitive date they can continue claiming it's a future technology even when nothing shows.