I've just noticed the amazing work done by Mellow Man in his collection of CODEF screens.http://codef.namwollem.co.uk
I don't know if Mellow Man is on the forum but the amount of conversions on there is amazing.
Every screen in the So Watt Demo converted to HTML5.
Not only has he converted them but everything is spot on.
I don't know his conversion process but he has actually worked out the sprite waves and everything. Did he have access to the original source code? Disassembling stuff with precalculated sin\cos and floating point maths in 68k is difficult (for me).
I thought those sprite waves were often precalculated in GFA and the actual demo simply includes them - but not in this case.
Still got, still working: Atari 4Mb STe, 520STFM, 2.5Mb STF.
Hardware: Cumana CSA 354, Ultimate Ripper, Blitz Turbo, Synchro Express II (US and UK Versions).