Of the machines from the 16-bit era, the Commodore Amiga arguably has the most active community decades later, and it’s a space which still has the power to surprise. Today we have a story which perhaps pushes the hardware farther than ever before: a demo challenge for the Amiga custom chips only, no CPU involved.
The Amiga was for a time around the end of the 1980s the most exciting multimedia platform, not because of the 68000 CPU it shared with other platforms, but because of its set of custom co-processors that handled tasks such as graphics manipulation, audio, and memory. Each one is a very powerful piece of silicon capable of many functions, but traditionally it would have been given its tasks by the CPU. The competition aims to find how possible it is to run an Amiga demo entirely on these chips, by using the CPU only for a loader application, with the custom chip programming coming entirely from a pre-configured memory map which forms the demo.
The demoscene is a part of our community known for pushing hardware to its limits, and we look forward to seeing just what they do with this one. If you have never been to a demo party before, you should, after all everyone should go to a demo party!
In the early days of computing, and well into the era where home computers were common but not particularly powerful, programming these machines was a delicate balance of managing hardware with getting the most out of the software. Memory had to be monitored closely, clock cycles taken into account, and even video outputs had to be careful not to overwhelm the processor. This can seem foreign in the modern world where double-digit gigabytes of memory is not only common, it’s expected, but if you want to hone your programming skills there’s no better way to do it than with the limitations imposed by something like a retro computer or a Raspberry Pi Pico.
This project is called Kaleidoscopio, built by [Linus Åkesson] aka [lft] and goes deep into the hardware of the Pi Pico in order to squeeze as much out of the small, inexpensive platform as possible. The demo is written with 17,000 lines of assembly using the RISC-V instruction set. The microcontroller has two cores on it, with one core acting as the computer’s chipset and the other acts as the CPU, rendering the effects. The platform has no dedicated audio or video components, so everything here is done in software using this setup to act as a PC from the 80s might. In this case, [lft] is taking inspiration from the Amiga platform, his favorite of that era.
The only hardware involved in this project apart from the Pi Pico itself are a few resistors, an audio jack, and a VGA port, further demonstrating that the software is the workhorse in this build. It’s impressive not only for wringing out as much as possible from the platform but for using the arguably weaker RISC-V cores instead of the ARM cores, as the Pi Pico includes both. [lft] goes into every detail on the project’s page as well, for those who are still captivated by the era of computer programming where every bit mattered. For more computing demos like this, take a look at this one which is based on [lft]’s retrocomputer of choice, the Amiga.
Classic demos from the demoscene are all about showing off one’s technical prowess, with a common side order of a slick banging soundtrack. That’s precisely what [BUS ERROR Collective] members [DJ_Level_3] and [Marv1994] delivered with their prize-winning Primer demo this week.
This demo is a grand example of so-called “oscilloscope music”—where two channels of audio are used to control an oscilloscope in X-Y mode. The sounds played determine the graphics on the screen, as we’ve explored previously.
The real magic is when you create very cool sounds that also draw very cool graphics on the oscilloscope. The Primer demo achieves this goal perfectly. Indeed, it’s intended as a “primer” on the very artform itself, starting out with some simple waveforms and quickly spiraling into a graphical wonderland of spinning shapes and morphing patterns, all to a sweet electronic soundtrack. It was created with a range of tools, including Osci-Render and apparently Ableton 11, and the recording performed on a gorgeous BK Precision Model 2120 oscilloscope in a nice shade of green.
If you think this demo is fully sick, you’re not alone. It took out first place in the Wild category at the Revision 2025 demo party, as well as the Crowd Favorite award. High praise indeed.
[James Sharman] designed and built his own 8-bit computer from scratch using TTL logic chips, including a VGA adapter, and you can watch it run a glorious rotating cube demo in the video below.
The rotating cube is the product of roughly 3,500 lines of custom assembly code and looks fantastic, running at 30 frames per second with shading effects from multiple light sources. Great results considering the computing power of his system is roughly on par with vintage 8-bit home computers, and the graphics capabilities are limited. [James]’s computer uses a tile map instead of a frame buffer, so getting 3D content rendered was a challenge.
The video is about 20 seconds of demo followed by a detailed technical discussion on how exactly one implements everything required for a 3D cube, from basic math to optimization. If a deep dive into that sort of thing is up your alley, give it a watch!
The demoscene never ceases to amaze. Back in the mid-80s, people wouldn’t just hack software to remove the copy restrictions, but would go the extra mile and add some fun artwork and greetz. Over the ensuing decade the artform broke away from the cracks entirely, and the elite hackers were making electronic music with amazing accompanying graphics to simply show off.
Looked at from today, some of the demos are amazing given that they were done on such primitive hardware, but those were the cutting edge home computers at the time. I don’t know what today’s equivalent is, with CGI-powered blockbusters running in mainstream cinemas, the state of the art in graphics has moved on quite a bit. But the state of the old art doesn’t rest either. I’ve just seen the most amazing demo on a ZX Spectrum.
Simply put, this demo does things in 2022 on a computer from 1982 that were literally impossible at the time. Not because the hardware was different – this is using retro gear after all – but because the state of our communal knowledge has changed so dramatically over the last 40 years. What makes 2020s demos more amazing than their 1990s equivalents is that we’ve learned, discovered, and shared enough new tricks with each other that we can do what was previously impossible. Not because of silicon tech, but because of the wetware. (And maybe I shouldn’t underestimate the impact of today’s coding environments and other tooling.)
I love the old demoscene, probably for nostalgia reasons, but I love the new demoscene because it shows us how far we’ve come. That, and it’s almost like reverse time-travel, taking today’s knowledge and pushing it back into gear of the past.
This article is part of the Hackaday.com newsletter, delivered every seven days for each of the last 200+ weeks. It also includes our favorite articles from the last seven days that you can see on the web version of the newsletter.
Want this type of article to hit your inbox every Friday morning? You should sign up!
The community of Hackaday readers is diverse and talented, and supplies us with plenty of motivation, feedback, knowledge, and of course cool stuff to show you. There are many interest streams within it, but it’s safe to say that we’re more directed towards the hardware scene here. One of those parallel streams which has much overlap is the demoscene, that area in which programming, art, and music come together and push computer hardware to the limit of its abilities in pursuit of the most eye-catching works. I took a road trip with a friend to Outline, a small demo party held on a farm in the eastern Netherlands, to take a look at the world of demos up-close as a hardware-focused outsider.
Like A Hacker Camp, But The Music’s Better
A still from Thrive, a 256 byte demo for the TIC-80 fantasy console.
If I wanted to sum up the flavour of Outline, I’d describe it as very similar to a small hacker camp, but with better music and partying. The hackerspaces are replaced by demo groups and awesome graphics take the place of robots and electronics, but the vibe of people with a passionate interest in the low-level understanding of technology is exactly the same. Even some of the same faces make an appearance. On the benches sit modern high-spec PCs alongside classic consoles and microcomputers, on the projector screen are live coding shaders or some of the most recognisable demos past and present, and in the air is an eclectic mix of live-DJ EDM and chiptunes.
As an outsider at a first demoscene event it’s difficult to appreciate the work from a comparative perspective, while like most of us I’m familiar with quite a few demos that have become popular I’m not well-equipped enough to talk about the code and techniques behind them But I can run through the various sections of the competition, and since everything is online I can link to a few of them. The competition is split up into several sections, which are loosely for all-out technology-no-object demos, space-limited 256 byte and 128 byte demos, and old-school demos for retrocomputing hardware. Each is a test of the programmer’s skill in fitting the most into the least of resources, and for those who appreciate such things it’s the cleverness of the technique which produces the demo that’s as much a draw as the look of the thing. I don’t think I have ever exercised such mastery over any of the computers I have owned. So browse the entries, and marvel at their ingenuity. My personal aesthetic favourites were Thrive by [Agenda] for the TIC-80 fantasy console and It’s about time by [Guideline] for Windows, but you may have different tastes.
Don’t Forget The Hardware
Mine Storm 4D, on a lenticular holographic display.
Beyond the atmosphere and the demos themselves, there was a bit of hardware for the retrocomputer enthusiast. The Atari Falcon and Jaguar were neither destined to set the world on fire when they appeared, but there they were for those of us who drooled over them back in the day to lust for once more.
If the original hardware wasn’t enough then there was some newly minted retrocomputing hardware making a showing, with a couple of minimig Amiga FPGA boards showing Workbench. Star of the hardware show though went to Mine Storm 4D, a version of the classic Vectrex game Mine Storm running on a PC, for the Looking Glass Factory holographic portrait display. With my visual superpower I didn’t quite get a 3D effect, but I definitely got the holographic effect when moving my head.
Having never been to a demo party I didn’t know quite what to expect, but I can safely say I had a fantastic time, saw a lot of really cool stuff, and made some friends along the way. If you’ve never been to a demo party because it’s not quite your scene then all I can say is that you should give it a go. Every hardware hacker should go to a demo party!
Would it have been too obvious to call a game about soccer playing RC cars, Soc-Car? Well [Martin] thought so and opted to call his Nintendo GameCube homebrew game, Retro League GX. The game clearly takes inspiration from Rocket League developed by Psyonix, as it pits teams of cars on a pitch plus comes complete with boosts to boot. There are some impressive physics on display here, and according to Krista over at GBATemp everything is playable on original hardware. Though those without a GameCube can certainly get a match in via the Dolphin emulator.
There are a number of ways to boot homebrew on a Nintendo GameCube, however, the most essential piece of software would be Swiss. Swiss is a homebrew utility that interfaces with all the myriad of ways to load code onto a GameCube these days. Common ways loading homebrew include saving files onto an SD card then using a SDGecko device that plugs into the memory card ports, or a SD2SP2 device that plugs into one of the GameCube’s expansion ports located on the bottom of the console. Those who prefer ditching the disc drive entirely can load homebrew via a optical disc emulator device like the GC Loader.
Still on the roadmap Retro League GX are ports for 3DS, PSP, Wii, and Linux. LAN and Online multiplayer are in the works as well. So at least that way GameCube broadband adapter owners may get to branch out beyond Phantasy Star Online for once. Best of all, [Martin] stated that the code for Retro League GX will be open sourced sometime next year.
