Sanity Roots 2.0 rotozoom effect

[crabman]

It's spinning so fast it looks like it rotates on more axes. But it's "just" a floor effect then, can't remember they worked when view from straight above, but apparently I'm completely wrong. Cool demo anyway.

Is the [ Show youtube player ] also a technical marvel?

[ReadOnlyCat]

Originally Posted by crabman

It's spinning so fast it looks like it rotates on more axes. But it's "just" a floor effect then, can't remember they worked when view from straight above, but apparently I'm completely wrong. Cool demo anyway.

Is the [ Show youtube player ] also a technical marvel?

The swan uses the same technique but on only one axis which allows the pattern to be much bigger.
If you look carefully you will notice shearing artifacts which betray the horizontal-shearing-vertical-stretching technique used.

[zero]

I do wonder if you could introduce a bit of perspective by just adjusting the pre-rendered lines, but that's getting way ahead.

[paraj]

Greetings amigos and amigas

This thread inspired me to give implementing the effect a shot. It's probably terribly buggy and incorrect (in particular it 'wobbles' when zoomed in a lot),
but it seems to be barely 1-frame using the non-expanded A1200 setup with WinUAE 3.3.0 (my amigas are in storage, so I haven't tried it on real HW yet).

Even when knowing how the effect should be implemented and with all the input here and in the threads over at ADA, I had trouble getting it to work. I never did get around to doing much coding on the amiga, so I had to read up on AGA and brush up on 68k-coding in the process. Massive props to Chaos for doing the original effect!

Thanks to everybody contributing here and at ADA.

I've attached source code and an executable version.

The source should compile with Asm-One (tested with v. 1.48) or Asm-Pro (v. 1.17).
68020+ and AGA (obviously) required.

[zero]

Amazing work paraj!

[zero]

Paraj, I've had a look at your code, it's an excellent effort. Really, well done for cracking this one, you deserve much credit for it!

[paraj]

Originally Posted by zero

Paraj, I've had a look at your code, it's an excellent effort. Really, well done for cracking this one, you deserve much credit for it!

Thanks, although all credit should go to the insightful and clever people here and on other online forums who actually figured out the details(I just (re-)implemented it poorly). And of course the original wizards!