Amiga Animation and CHIP RAM versus FAST RAM

[Damion]

--edit-- Old progressive resolutions are indeed capable of 50/60 fps :/

Bottom line -- NTSC video (like Amiga/ST used) is capable of displaying 30 frames per second, or 60 interlaced fields per second. Amiga/ST monitors are probably not capable of displaying 60 non-laced (progressive) frames per second.

Conclusion -- there is essentailly *no* difference between Amiga and ST fps capability on non-laced screens (aside from Amiga advantage of better quality graphics). Whatever you were changing with the function keys to get "60 fps" sounds like some kind of marketing gimmick.

Do some research on NTSC video here:

http://en.wikipedia.org/wiki/Ntsc

Rowbeartoe wrote:

tonyp12 wrote:
If all the frames in raw format would been able to fit on chip ram:

Then 60fps would be not problem and would only use
1% cpu power as just simple changing the mem pointer in the copper list.

But if you use delta compression such as IFF anim when the cpu would have to go to work

And if you have to copy from fast ram to chip ram you could not use the blitter.

I was watching these demos at my work on an Amiga 500- that translates to all Chip RAM.  Again, I keep reading the Amiga can, or the Amiga should have no problem, or the Amiga has no need too, but the reality is, in my visual experience at the time, the Amiga animation demos, as with Sculpt 3D, or Antics Cad 3D 2.0, or the Juggler Demo, these animation programs stopped at no greater than 30fps.  My question again is, why? And is everyone that says it can, better programmers than the software makers of these programs, or is it because of other reasons?  I'm just curious, because the Atari ST was pounded for being inferior by experts all the time, and i really don't care what was better- to me it was a win win, because Amiga to be is an Atari computer (sorry if that upsets Amiga fans), and I enjoyed my Atari ST software very much as well.  I keep reading all my old magazines reviewing animation software or demos, and none mention 60fps as was bragged about with Atari ST's Cad 3D and shown all the time with Spectrum 512 page flipping.  Again, if the Amiga was limited to this page flipping, was it just the software, the speed of Chip RAM, the 7.1 MHz clock speed, the more memory intense files?  I duno.  sigh.

Thanks again everyone for trying to help.

[Damion]

Zac67 wrote:
NTSC and PAL are very well capable of displaying full 60/50 fps NON-INTERLACED. In interlace mode the frame rate drops to half, but vertical resolution doubles (same horizontal scan rate of course).

DOH! I stand corrected, 240/288p is indeed capable of 50/60 fps. The fields are scanned one atop the other twice as fast, at half resolution of normal interlace. (I suppose there'd be quite a bit more flicker if it was done the way I was thinking). Seems *I* needed to do a bit more research, LOL ;-)

[Damion]

One question though:

"We even had Antic software with Cad 3D 2.0 on both computers, but the Amiga was limited to 30fps at best."

Everything I've searched sez CAD 3D 2.0 was an ST only program?? So I'm wondering how you had them both side by side running the same software/animations… It would be interesting to know what exactly the Amiga was running, since (once again from what I’ve researched) Antic CAD 3D 2.0 was basically considered the pinnacle of the genre on the ST (yet, in reading the old reviews I find no mention of the "highy advertised 60 fps" thing)... so if you were comparing that to some ropey PD software on the Amiga, that could definitely explain it.

I also found this interesting bit (more on this page):

"Yet the biggest new feature by far in CAD-3D 2.0 was the ability to render to the new "delta-compressed" animation format developed by Mark Kimball. The basic idea was to start with a picture, and then for each subsequent "movie frame" store only the parts that change, rather than storing each frame as an entire picture, thus wasting data. Mark Kimball implemented this process as an Atari ST desk accessory called Cyber Smash."

Anyhow, after reading the entire thread (and exercising some common sense), it's obvious the OCS Amiga would have no problem matching/surpassing the ST's animation skillz, one guy even posted the code to prove it. Whatever differences existed were down to file formats (with tricks/gimmicks like posted above) or screenmode differences, not the actual hardware. (I would imagine raising the small MHz difference is a non-sequitur in light of the Amiga's co-processor scheme.) Also (as has been mentioned), there were a ton of 60 fps games/demos running on low-res screens (glad I got that sorted ) on OCS machines, and a ton of graphics/animation software available (which was not limited to 320x200 and 16 colors like Cyber Paint btw). As the Amiga was basically the home animation "King" at the time, I’m sure both the hardware and software was able to match whatever the ST could do. (As an aside, anything intended for broadcast would obviously be 30 fps/interlaced due to NTSC broadcast regulations.)

[Damion]

Juggler, Sculpt 3D,

Sculpt 3D was the first animation program for the Amiga (what Juggler was done with), maybe that had something to do with it. Again, the authors may not have seen a point (for reasons already listed).

and this Demo of CAD 3D on the Amiga

Link?

this is about my question as to why Amiga animation software appeared to always be limited to 30fps on the store Amiga 500.  hmmmm.

So all we've really established here is that whatever was running in your store (you seem to not be sure, or think it might have been "demo" software) may have been limited to 30 fps, and not "all Amiga animation software." Why not research the mountain of other Amiga animation titles (aside from the very first one in '86) and see what ya come up with?

[Damion]

In addition Juggler was not Scult 3D.

Not technically, but kind of:

http://home.comcast.net/~erniew/juggler.html

"Eric rendered the frames in a raytracer he wrote called ssg, a Sculpt precursor. The rendered images were encoded in the Amiga's HAM display mode and then assembled into a single data file using a lossless delta compression scheme similar to the method that would later be adopted as the standard in the Amiga's ANIM file format."


In regard to Zoetrope, I have no idea what the limit was. (Nor can I find anything about max fps with Cyber Paint, btw.) I will stress again though that anything intended for NTSC broadcast would obviously be limited to 30 fps. (Some Amiga programs did however take advantage of "field rendering" (60 fields/sec) in interlaced modes, for the appearance of smoother motion. Naturally, this would be a non-issue on the ST since there were no laced modes.)