---
title: "demoscene-recomp: classic PC demoscene productions running natively in the browser"
slug: demoscene-recomp-classic-pc-demoscene-productions-running-natively-in-the-browser
url: https://listedarticles.com/articles/demoscene-recomp-classic-pc-demoscene-productions-running-natively-in-the-browser
canonical_url: https://treylorswift.github.io/demoscene-recomp/web/
content_type: announcement
language: en
published_at: 2026-10-08T11:09:49.551Z
updated_at: 2026-10-08T11:09:49.551Z
authored_by: human
publisher: "demoscene-recomp"
publisher_url: https://github.com/treylorswift/demoscene-recomp
topics: ["Demoscene", "WebAssembly", "Emulation", "Retro Computing"]
license: all-rights-reserved
word_count: 221
reading_minutes: 1
citation: "demoscene-recomp. \"demoscene-recomp: classic PC demoscene productions running natively in the browser.\" 8 Oct 2026. https://treylorswift.github.io/demoscene-recomp/web/ (all-rights-reserved)"
---

# demoscene-recomp: classic PC demoscene productions running natively in the browser

> demoscene-recomp runs Future Crew's Unreal and Second Reality, Triton's Crystal Dream II and NoooN's Stars in the browser by recording every executed x86 block in an emulator, translating it one-for-one into cycle-timed C, compiling to WebAssembly with timer, VGA and Sound Blaster models, and checking it event for event.

# demoscene-recomp

─═≡ Classic PC demoscene productions running in the browser. ≡═─

## How It Works

Each demo's original DOS code, recompiled instruction for instruction, runs in your browser:

1. The demo is run on an x86 emulator that records every block of code the CPU actually executes, over the whole demo.
2. That recording is translated into C - the original instructions, one for one, with the exact cycle timing of the emulated machine.
3. The C is compiled to WebAssembly, together with models of the hardware the demo talks to: the timer, the VGA card and the Sound Blaster.
4. The result is checked against the emulator event for event: every interrupt, port access and frame at the same moment of emulated time.

The demos' own loaders, music players and effects all run as they did in 1992 and 1993; only the hardware is modelled.

The demos ran on VGA at 70 Hz, so they look smoothest on a display running at 70 Hz, or at 140 Hz or higher.

[demoscene-recomp on GitHub](https://github.com/treylorswift/demoscene-recomp)

## Credits

Unreal and Second Reality are by Future Crew, Crystal Dream II is by Triton, Stars: Wonders of the World is by NoooN; all were released free to the demoscene.

The original release files are served unmodified, as the demos read them at run time.

Font: IBM VGA 8x16 by VileR, int10h.org ([CC BY-SA 4.0](https://treylorswift.github.io/demoscene-recomp/web/assets/FONT-LICENSE.TXT))