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Source code for 4kb demoscene production “Elevated” released

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Re: Source code for 4kb demoscene production “Elevated” released

#51
post #31

Does this mean that lots of 3:30 minutes 1080p videos could be compressed into 4kb? EDIT: We can be generous and say 40kb for sake of adding more colours / etc.

Take a look at https://en.wikipedia.org/wiki/Kolmogorov_complexity

The Kolmogorov Complexity of a video (or any other data) is the size of the shortest program which outputs that video then halts. This 4k executable is similar in spirit, but also follows strict rules about efficiency: Kolmogorov complexity places no time limits on that shortest program, whereas this program must output pixels fast enough to make the video realtime.

Re: Source code for 4kb demoscene production “Elevated” released

#52
post #50

Back in the day demos were more impressive imo. A lot of them now use direct x or opengl. For the most part the stuff you see isn't written by hand anymore AFAIK, they just have programs to generate the actual demo. Basically they use modeling programs.

While true for large demos, the 4kb — perhaps even 64kb? — are still written very much by hand.

Re: Source code for 4kb demoscene production “Elevated” released

#53
post #21

Earlier quoted context omitted.

You seem to think that GPU programming is somehow easy. You should try it and see what you think. Yes, there is massive amount of power available but it's not easy to use effectively. You need a different mental model how things work, there's very little shared state and all the algorithms used have to match the model of computation. Using the GPU almost exclusively, generating everything procedurally is a massive ac…

I used to do GPU programming. Brief foray into it for game programming plus a then-new field called "GPGPU" pushing its limits. Think I implemented some crypto or physics stuff on one. I've followed some of the recent efforts. My points of comparison are what they're doing vs what it's designed to do with what vs what other people do with that and other hardware. It looks great with lots of efficiency. I'll give them…

Pre "GPGPU" era of mostly fixed function 3d accelerators is hardly comparable to modern programmable GPUs.

> It's just way less impressive to me given they're using a powerful graphics card to mostly do what it's designed to do ...

This demo isn't at all what the GPU is "designed to do". The all-procedural graphics is way different from drawing artist-generated 3d models from memory while being orchestrated by the CPU. While it is more commonplace today, this demo was pioneering work in "all GPU" procedural graphics.

Re: Source code for 4kb demoscene production “Elevated” released

#55

That's unreal. On what kind of graphics hardware, though? Seems like it probably offloads most of the work on GPU whereas we'd have had to do most of it in software on HW weak enough that 4KB size actually mattered. And probably not achieve this demo.

The 4kb restriction isn't there to make it run on weak hw, it's there to push people.

However it does irritate me that it's pregenerating the entire scene in memory. Being allowed to use 300MB of RAM doesn't strike me as very limiting.

Re: Source code for 4kb demoscene production “Elevated” released

#56
post #40
post #34

Earlier quoted context omitted.

Sorry, I thought it was obvious, but the question is: Could procedural generation be used to achieve amazing compression rates given a currently impossible to code algorithm?

"39. Re graphics: A picture is worth 10K words - but only those to describe the picture. Hardly any sets of 10K words can be adequately described with pictures." It's the pigeonhole principle; there are only a few long videos possibly encodable as short programs because there are only a few short programs in the first place. To get compression performance, one has to target an ever smaller subset of possible videos,…

> It's the pigeonhole principle

Is it really? Could a human meaningfully distinguish between 2^4096 different 4 minute videos?

Re: Source code for 4kb demoscene production “Elevated” released

#57
post #52
post #50

Back in the day demos were more impressive imo. A lot of them now use direct x or opengl. For the most part the stuff you see isn't written by hand anymore AFAIK, they just have programs to generate the actual demo. Basically they use modeling programs.

While true for large demos, the 4kb — perhaps even 64kb? — are still written very much by hand.

I hope so. I'm not involved with the scene at all, but I did read a bunch of history about the scene and watched tons of demos.

I think farbrausch was one of the major groups who did this sort of thing https://github.com/farbrausch/fr_public

Re: Source code for 4kb demoscene production “Elevated” released

#58

Earlier quoted context omitted.

The 4kb restriction isn't there to make it run on weak hw, it's there to push people.

However it does irritate me that it's pregenerating the entire scene in memory. Being allowed to use 300MB of RAM doesn't strike me as very limiting.

"Being allowed to use 300MB of RAM doesn't strike me as very limiting."

BOOM! I knew it was going to be huge. That's a beefy GPU + 300MB in RAM + pregenerating. I'd have... made sacrifices to have that even in the Half-Life 1 days. :)

Re: Source code for 4kb demoscene production “Elevated” released

#59
post #48

Earlier quoted context omitted.

"It would be impossible since pixel shaders didn't exist until the 2000's ;-)" Lmao. You got me there. "Just turn it into a function and call it for every pixel on the screen. Making it fast is another matter altogether though." I was imagining it took up many MB of memory and massive cycles even on a multicore CPU. Suddenly, one faces tough decisions about organization, resolution, primitives, techniques used, algor…

A soft renderer wouldn't fit in 4096 bytes, too. The overwhelming preference of the demoscene when doing PC filesize compos is to lean on OS provisions in order to free up space for more algorithms. Hence you have demos that use files in C:\Windows as source data. Likewise, you have demos for older computers that require aftermarket RAM upgrades and employ preprocessing techniques that require modern computing resour…

"It's all fairly arbitrary stuff, and in the end, the point is to present something cool running on the hardware and within the nominal restrictions, even if you get tricky to do so."

Another good, detailed perspective on it. Appreciate it. I'll especially agree with the part I quoted. :)

Re: Source code for 4kb demoscene production “Elevated” released

#60
post #53

Earlier quoted context omitted.

I used to do GPU programming. Brief foray into it for game programming plus a then-new field called "GPGPU" pushing its limits. Think I implemented some crypto or physics stuff on one. I've followed some of the recent efforts. My points of comparison are what they're doing vs what it's designed to do with what vs what other people do with that and other hardware. It looks great with lots of efficiency. I'll give them…

Pre "GPGPU" era of mostly fixed function 3d accelerators is hardly comparable to modern programmable GPUs. > It's just way less impressive to me given they're using a powerful graphics card to mostly do what it's designed to do ... This demo isn't at all what the GPU is "designed to do". The all-procedural graphics is way different from drawing artist-generated 3d models from memory while being orchestrated by the CP…

"Pre "GPGPU" era of mostly fixed function 3d accelerators is hardly comparable to modern programmable GPUs."

Which people used to do things they weren't designed for at all in so-called GPGPU work. The results defaulted on really, clever work. It's why I brought it up.

"The all-procedural graphics is way different from drawing artist-generated 3d models from memory while being orchestrated by the CPU. While it is more commonplace today, this demo was pioneering work in "all GPU" procedural graphics."

This is where I likely slipped up. I forgot how old this one was. I retract that claim then.

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