Stippling As Fast 3D Technique

An anonymous reader writes "This Stippling effort wins best paper at IEEE Boston conference. Could real time medical rendering be whizzier than Id?"

Comments

It's really not that far out

[Frothy Walrus]

Stippling is just the application of small, uniform polygons (aka "dots") in rendering images. To modern graphics hardware, a dot may as well be a polygon, so we haven't gained much in practical terms.

Re:It's really not that far out

[pVoid]

To modern graphics hardware, a dot may as well be a polygon, so we haven't gained much in practical terms.

Actually, modern hardware can be made to render dots only (ie vertices of polygons/triangles) as opposed to rendering the whole shaded surfaces. It's not a hack by making a small enough surface that looks like a dot, it's just actually rendered as dots. For those interested to see, there's a demo for nVidia cards where you can tell it to render dots only...

I haven't read too much detail about this, but if IEEE says it's the best paper, they must be doing something different than normal cards are doing, ie probably bypassing normal rendering methods which use matrix multiplications heavily, and instead making some small assumptions - like maybe no perspective correction - and going with faster smaller transform equations...

If that's not the case, I give them a *yawn*.

No polygon replacements.

[DarkHelmet]

If you look at the bottom:

Abstract

NON-PHOTOREALISTIC VOLUME RENDERING USING STIPPLING TECHNIQUES

This is obviously a compromise approach. There's no way this would be able to make photorealistic games.

The difference between medicine and gaming is that with medicine, you have a real-life object whose structure whose PROPERTIES you're trying to recreate realistically, regardless of how off-color or computer generated it appears.

With gaming you have an object that's computer generated, whose APPEARANCE you're trying to recreate, with lesser regard to the properties within that object. For instance, most gaming models consisting of polygons have hollow insides...

People at Id don't bother to render and model the organs. People in medicine don't care about having models of human hearts bumpmapped or glossy.

This is supposed to be news for nerds. What's with all the mindless generated hype?

Re:No polygon replacements.

[good-n-nappy]

IIRC one of the biggest advantages of stippling in rendering surfaces is that you can get a fast simulation of transparency. Check out here. So maybe the same applies in 3D. The 3D stippling might allow you to simulate complex semi-transparent volumes - perhaps also avoiding some z sorting or alpha blending.

Also, maybe you WOULD see more of this in games if it could be done in real time. Just because all we have now is polygons doesn't mean that's the way it has to be.

I don't see what's new or novel about this

[Ryu2]

Essentially, they are just using a different primitive (point) instead of splat or voxel, traditionally used in volume rendering visualizations.

Most of the complexity in volume rendering consists of preprocessing the data (alpha testing would be a simple way, other methods involve transformations into the frequency domain, etc.) to reduce the asymptotic complexity of the set to be rendered from the naive O(n^3) to something which corresponds to the actual visible set, not the actual rendering itself.

I don't think they are doing anything different in this stage -- it's still the same dataset that needs to be worked with, after all.

While on the subject of real-time filters...

[hackshack]

The trend in game engines is, as it has been in the past, largely towards better image quality. The stippling technique described in the article is a tradeoff for those who'd rather have the medical equivalent of "better framerates."

That said, you CAN have sketchy-looking Quake if you want with NPRQuake. I've tried this and it looks incredible- it's a shame no commercial games have used this technique yet. Reminds me of that 80s music video where the gal walks into the mirror, and everything's all "pencilly-looking" but in real-time... now what was that damn song? (racks brain)

Also check out Waking Life. It's available on P2P as I write this, but you didn't hear that from me, and you're better off renting the DVD for all the extra goodies. It's not as pretentious as many make it out to be, and the visuals alone are worth it.

Next advancement in medical imaging

[Woogiemonger]

Rumor has it, doctors will soon be rendering a patient's internal organs with ASCII art.

Not really that exciting

[Temporal]

Could real time medical rendering be whizzier than Id?

Probably, but not because of this. This technique would have very little use in a gaming environment. Indeed, algorithms indended for medical imaging rarely do. In this particular case, the dotted images don't really provide any sort of occlusion. That is, you can see right through the image to whatever is behind it. Great for medicine (where the whole point is to see inside the patient's body), bad for games.

As a matter of fact, when I read this, my only thought is "well, duh". I do 3D graphics myself, and I am having a hard time believing that this technique is new. Particle system rendering? There must be something more to this that the dumbed-down article isn't telling us. Maybe they have a new, advanced algorithm for deciding exactly where to place the dots... that really must be it. As long as we're reporting on low-level algorithms, I have a new algorithm I came up with for drawing borders on the silouette edges of cartoon renderings efficiently. Do you want to hear about it? No? Aww...

Downloadable

[jki]

They have made the renderer available, here (win 2000 only). I don't think I have the interest to see further than just trying whether it works for me, but if someone does, please let us know if you find anything worth commenting :)

Um. What is this crap?

[DrunkenTerror]

This article sucks, and the /. write-up sucks more. It has virtually nothing to do with id, Doom, or games in general. They're visualizing data sets, not shooting rockets at each other at 60 FPS (or 8 fps in the Doom3 demo ;). Rendering static, previously collected data Vs. On-the-fly rendering of a rapidly changing dynamic environment.What should one expect from an anon submission, though? :P

And how bout these amazing captions? They read like a typical /. dupe. (similarities highlighted)

IMAGE CAPTION 1: This image of a human cranium was created with a new kind of computer-imaging software that uses the ancient technique of stippling to convert complex medical data into 3-D images that can be quickly viewed by medical professionals. Data from CT scans were converted into dots to create the stippled image. Cave dwellers and artisans used stippling thousands of years ago to create figures by painting or carving a series of tiny dots. More recently, 19th century Parisian artist Georges Seurat used the method, also called pointillism, to draw colorful, intricately detailed works. Because dots are the most simple visual element in a picture, they also are ideal for computer visualizations.

IMAGE CAPTION 2: This picture of a human foot was created with a new kind of computer-imaging software that uses the ancient technique of stippling to convert complex medical data into 3-D images that can be quickly viewed by medical professionals. In this image, data from CT scans were converted into dots to create the stippled image. Stippling uses tiny dots to create an image. Because dots are the most simple visual element in a picture, they also are ideal for computer visualizations.

Oh well, at least their subjects and verbs agreed in number. (...data... ...were...)

you'd think it's simple, but it's not

[bbc22405]

I'm reading lots of comments about "how is this different from just plotting pixels?" and such. If you were given a voxel dataset, and were given the job of showing the internal structure, in a nifty, sorta-transparent, sorta-3D way ... you would likely fail.

It is not as simple as it seems. You want the nearer bones (or whatever structure) to show up more, but not completely obscure what is behind. And you want the stuff behind to look "behind". But how?

It is not the same problem as calculating normals of polygons to see which surfaces are facing the viewer, sorting things by depth, and finding out what is completely obscured by what else. Go back, and think again.

I'm guessing (without reading the paper), that the point of using dots is that the dots are not infinitely small, but rather have a small measureable size, and so the nearer dots are drawn larger, but that all dots are small enough that they don't tend to "hide" each other in the Z direction, but rather "pile up" a bit to make the piled up places darker. This sort of "implementation" is interesting I think solely because one might be able to implement it in a way that makes use of fairly standard operations implemented by vroomy graphics hardware. (Ie. it is not otherwise an obvious implementation of the desired operation, and I'll guess that the initial reaction of the people who built the graphics hardware/driver is "hey, you're abusing it!", followed almost immediately by "wow, cool!". It's as absurd and wonderful as if you drew a cloud of smoke between you and another object by drawing each particle in the cloud.)