90s demo effects ported to WebGL

[george]

Spinning this off so I don't derail the .MOD thread. Based on this static dissection of DOPE by Complex (1st PC demo at TG'95, MS-DOS, 320×200 mode 13h): https://demo2.jeskola.net/dope-analysis.html

Rebuilt its effects live in WebGL (attached). All the real-mode tricks are toggles: fixed-point 3×3 rotation, divide-by-depth projection, radix polygon sort, additive overlays, nibble/palette hacks. Two-pass like the original — 320×200 work buffer → fake "VGA blit" with palette ramp + scanlines. Plus 4K/retina upscale (up to ×8 internally) with a chunky-pixels switch.

The analysis driven on a GPU instead of a 486 took the LLM about 5 minutes. Perfect as a starting point for audio visuals.

[oskari]

it's an interesting idea but you should make it so that i don't have to unzip

[george]

Yeah, sorry, it's annoying. https://free-moccasin-lsirwj6e.edgeone.dev

[oskari]

yeah not very good.

i think you could make better by the descriptions. have every part and stuff. i should have made it have time stamps of course.

[oskari]

i asked it to add time stamps so dope etc should have them soon

[oskari]

i think it updated https://demo2.jeskola.net/dope-analysis.html at least

[george]

The new output is impressive. It's much better for learning!