Unless I'm overlooking something, the demo only requires DOSBox to have a machine with predefined execution speed. There are no DOS interrupt calls that I can see. Other than that, the program could probably even be trivially modified to fit in a floppy disk MBR and could potentially run without underlying OS.
To be more exact (in an excessive way), it uses the BIOS's code to set the video mode (INT 10h) which is probably a few dozen bytes (at least?) although I have been remiss at not ever reading them. And it depends on DOS configuring the memory space to leave an INT 20h call (to terminate the program) at a place that's easy to RET to. But, yeah, very little extra. But I'm not being negative at all and this is pretty nice code and on the impressive side of 256 byte demos from the 80s and 90s (and onward).
Yes, this is very minimal; if it were self-booting the INT 20h call wouldn't be needed, but there's no getting around the INT 10h, unless you specialize for very specific hardware.
The entire 5150 BIOS fit in 8k, so even if it were laden with BIOS calls (which it's not) then that would be an upper-bound.
Also, MIDI - I'm not very familiar with demo programming, but I guess using MIDI saves a lot of bytes compared to trying to do something similar with only the PC speaker?
Sure, it saves a lot of bytes compared to PCM encoded wave-form data, but it's not really cheating anything unless we also consider the red, blue and green parts of the computer monitor to be cheating because we're not outputting colours as raw wavelengths, but instead the monitor is decoding compressed signals into actual colours.
What is this "cheating" you speak of? I wasn't expressing any judgement, just saying that using MIDI helps save bytes. But now that you mention it, the bitmapped graphics that we take for granted nowadays also help (it gives you a whole memory space to work with that doesn't count towards the length of your program, rather than having to "race the beam" -https://en.wikipedia.org/wiki/Racing_the_Beam). Not sure if there's a demoscene for the Atari 2600, but that would probably be the most "bare-metal" you could get...
Why is that bad? If the bytes could easily run within the same constraint in another env/language why the hate?
I am with u on the excessive ram of browsers. It is insane. Still, it is one of the most portal and easy ways to share something. Heck, u can run a dos emulator in your browser.
This is probably in reference to things like Dwitter.net (https://news.ycombinator.com/item?id=46557489), where the browser (plus the Dwittet-specific runtime harness) contributes significantly higher-level functions than traditional demoscene targets like DOS PCs.
It’s just a different thing. I see no “hate”, only an expression of preference for “bare-metal” demos.
Yeah, but it's a slippery slope, because no program runs in complete isolation. Even on the simplest 8 bit machines where there is no OS to speak of, you are still benefitting from the capabilities of the hardware - generating sound and music with the C64's SID takes a lot less bytes (and still sounds much better) than trying to do something comparable with more primitive hardware like the PC speaker. That's probably also the reason why this demo uses MIDI.
if your OpenGL driver had a glDoACoolDemo(); function, you wouldn't be allowed to call it. But if you find that among the regular functions are some code blocks that just happen to form a cool demo, you can use them and take credit for your discovery...
Probably because JS has larger runtime, in JS you don't have to write about most of the low level code. So it's easier to squeeze code in JS than in ASM or machine code.
That actually deserves a competition of its own. Just what can you accomplish with a 256 bytes prompt? Or maybe 32 bytes, to compensate for expressiveness of natural language.