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[Soulwynd]

Not sure. It's much simpler to figure it out than it is to program it in some usable form. You'd probably start like that 2.5yo claydoo engine he had.

Major questions I have are:

1. If the atoms are really quads/tris how does he draws them when they're big enough to be more than a single pixel?
2. Still part of question 1; If he draws a quad on screen when really up close, which can save some engine time, how does he decide when to draw another quad that may be on front of that one. Is there some sort of z-buffer too?
3. How does his instancing works? That's one of the major points there, because that scene in the demo only works because he has thousands of instances of the same thing.

Alright, but, I'm still confused as to how the data in the object is arranged?

I don't know either, but I think it is probably organized in:
points -> tris -> quads -> atom

Atoms probably have only the following data:
position, radius, color, quad pointer

So, at a certain distance, you know the radius will only fill up a pixel at most, so you -don't- have to look at the polygons to render that pixel. Only really close up images or low resolution objects would require you to look at the polygon. Which is the complete inverse of how our 3d graphics work right now.

Which brings me to another question, how does he anti-aliases it when several atoms could fit in a single pixel? Does he interpolate the color or just pick the most relevant atom? The way he speaks about it makes it sound like it only picks a single atom to fill the pixel, but I think that would create noise and possibly too sharp images.

[woose1]

Which brings me to another question, how does he anti-aliases it when several atoms could fit in a single pixel? Does he interpolate the color or just pick the most relevant atom? The way he speaks about it makes it sound like it only picks a single atom to fill the pixel, but I think that would create noise and possibly too sharp images.

Everything looks really smooth, even when zooming in really far, so he probably mixes the colors (assuming that there would be 2-3 atoms per pixel when you get too close). I think if he suddenly started switching atoms, you would see that 'jumping effect', which he prided himself on not having. Again, he has to protect certain trade secrets, so he probably simplifies it for his interviews and videos.

[Soulwynd]

Switching atoms would give it noise instead, which is very common in voxel engines.

And you don't perceive the atom->polygon transformation because it should only occur when a atom is filling more than one pixel. To be fair, it's not really an atom to polygon transformation. It's just a single atom painting more than one pixel.

[Tharwen]

This page makes me angry: http://unlimiteddetailtechnology.com/description.html

"perfect pure bug free 3D engine"

THAT MEANS NOTHING

EDIT: Oh, and on a slightly less rage-y note, this image clearly shows that they use repeating structures to minimise memory usage:

Spoiler (click to show/hide)

EDIT 2: Why can't the noise issue be solved with antialiasing? Surely if an atom was obscured by the colours of the atoms around it it would not pop in so dramatically.

[Soulwynd]

Yes, I think I mentioned things were instanced a lot to make it look huge. That's done with conventional 3d graphics too.

Well, I haven't seen noise on their engine and it's not antialiased either. Not that antialiasing fixes 'voxel' noise, but that's another thing altogether. I mentioned it because he constantly claims it picks a single atom to fill a pixel and that's what causes noise. For an example, for a distant object, a pixel on the screen is able to fit like 10 atoms. So which one does he pick? Will a 0.0001 degree change on the view make it pick another atom of those 10? That's what causes noise in voxel engines. 

May not seem like a huge issue, but you have to remind yourself that if you add a single extra command per pixel on a 1280x1024 screen, that's an extra of 39.3 million commands per second at 30fps. So less work is better.

If he does a traditional oversampling to do a x4 AA, that's literally four times more work than not using traditional AA. It works on our current graphics because a lot of the transformations done to the polygons are -not- resolution dependent. They're done in screenspace using floating points, so they can adapt to any resolution you're using and still look good.

[Sordid]

Yes, I think I mentioned things were instanced a lot to make it look huge. That's done with conventional 3d graphics too.

I don't really see that as a problem. As you say that's done with conventional graphic as well. If you're making a game, you're not going to make thousands of unique trees, are you. You're going to make maybe a dozen and then just copypaste them. You do that whether you're working with polys or voxels.

[Soulwynd]

I don't think it's a problem. It just proves Notch is a douche.

[Jackrabbit]

Or is cynical, which I think would be a kinder analysis.

[Soulwynd]

That's a good point, Jackrabbit. Except I'm not known for being kind to people who say bullshit. Had he said:

"I don't think it's possible. To be honest I think It might be a scam."

I wouldn't call him a douche and would actually agree partially with his opinion. You see, it's the same one, it's just not worded as:

"They’re hyping this as something new and revolutionary because they want funding. It’s a scam. Don’t get excited."

Not only that but his explanations of why are inane. I mean, I've never made money out of programming, it's a hobby to me, but I know better than assuming the things he assumed and present them as granted. I mean, I was assuming it was raytracing until I saw the latest interview and I was wrong in that assumption and my assumption changed accordingly. Whenever I assume something, I try to be clear and say "I think this is how it is" or something similar. But instead, Notch said this:

"They made a voxel renderer, probably based on sparse voxel octrees."

As it is, that was a very douchey way of putting his opinion on something he had no way of being sure of. Being cynical and doubting it is alright, I mean, I still have my doubts and could find a scam around the corner, I just know better than going around in a blog that is seen by thousands of people and screaming "It's a scam, here's why:"

[counting]

Notch is just being Notch

But seriously, I think it doesn't actually describe things in voxel as in "little boxes" at all. It literately is just many many dots (atoms). If you put enough dots on the surface, from a distance it will form a smooth surface.

And if you come up closely and see the early version (7 years ago), he showed in the interview, its like the atoms are spreading it's color to it's neighboring volumes, not predefined a volume of box. It is thinking in reverse at the basic level. Like you see the demon figures in the shape of many white dots. It is just using limited dots to "describe" the statue surface. And since it's limited, it not hard to calculate every surface atoms.

I think it started as a predefined/calculated bitmap (first frame), and every change in viewpoint will affect only the edge atoms. So it only "regroup" those atoms and add/remove the boarding atoms into average, hence no need to recalculate all. Then the bitmap is updated using this new average map. But going into really close up, it has to filling the gap pixels between atoms, that's when the jumping happens. (It actually won't happened, when viewing at far enough distance. since there are enough atoms to fill in every pixels).

This is my opinion anyway. The transformation using sin, cos can be done quite quickly if you use look up tables. (you don't have to recalculate every pixel, but only when the shift of view angel is large enough, then recalculate the edge atoms included into the view.)

[Soulwynd]

That's a regular voxel engine. He made sure to say it's not a traditional voxel thing. So I think it's closer to what I said. But that's my assumption on the matter.

[counting]

That's a regular voxel engine. He made sure to say it's not a traditional voxel thing. So I think it's closer to what I said. But that's my assumption on the matter.

I am no expert in computer graphics, so I can't really tell. At least Notch is right in one thing, it doesn't reveal very much details, and not showing it's weakness/limitation much.

[Dakk]

New videos are up, including an interview. No animations yet though, so my skepticism has yet to be quenched.

The interview has a real time demo of the island from the original video.

[lordcooper]

New videos are up, including an interview. No animations yet though, so my skepticism has yet to be quenched.

The interview has a real time demo of the island from the original video.

So, this thing is real?

[nenjin]

New videos are up, including an interview. No animations yet though, so my skepticism has yet to be quenched.

The interview has a real time demo of the island from the original video.

So, this thing is real?

/Morpheus

How do you define "real?"

/Morpheus

I think it's real enough in the sense that a game could probably be made with it. What's in question is what the scope of a game made with this engine ultimately is. He's saying it's "out there." Everyone else is saying "back over there."