Originally Posted by NovaCoder
I think almost all demos are pre-calculated.
Originally Posted by StingRay
That is, quite frankly, far away from truth, most demos are 100% realtime.
When you watch a demo and see an effect that looks much more impressive than the others, it has very likely been precalced/prerendered. Often, demos also have animations of course, but for the most part it's clear to the viewer that it's an animation.
If you download Vision, you can see the 400KB animation file, but of course you don't see the files or even the filesize at compo time (or on Youtube). So in this case it's a bit devious since the framerate is so slow. And so you think they could maybe have done the impossible.
Of course, it all becomes clear if you run it on a real Amiga or emu matching compomachine specs.
There are various ways to make impossible things possible, f.ex. animation, precalc, prerender etc. There are some famous ones, I don't know if Alpha and Omega was first. It's obvious to a good coder that it's precalced, but that's usually a tiny part of the audience.
You can test it out in WinUAE by doubling or halving the CPU speed and see if the framerate changes.
There are two schools of thoughts on the realtime thingy. One is that realtime should be realtime and the other is "who cares?". Mostly, the realtime phalanx accepts general-purpose tables (ie. not made for the effect) on lower-spec machines.
Also check out Dual Crew/Shining (DCS) and Skarla.
From what I gather A1200+Fastmem was not the stock platform like OCS/1MB is, 030 cards arrived pretty quickly and was accepted as demoscene platform.
The substantial advantage of Falcon to A1200+Fast only is that chunky mode and playing wav comes for free, so the CPU can just render. A 68030 vs 68EC020 at the same bus width and frequency is roughly 2.15x faster, with the faster clock that would be 2.46x faster.