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From: walrus@wam.umd.edu (Udo K Schuermann)
Newsgroups: comp.sys.amiga
Subject: Re: Doing animation to flopticals, and Re: Imagine
Message-ID: <1990Dec16.221147.3620@wam.umd.edu>
Date: 16 Dec 90 22:11:47 GMT
References: <86758@tut.cis.ohio-state.edu> <61534@masscomp.ccur.com> <1990Dec13.201243.4265@wam.umd.edu> <1990Dec15.042510.14514@zorch.SF-Bay.ORG>
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Reply-To: walrus@wam.umd.edu (Udo K Schuermann)
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In article <1990Dec15.042510.14514@zorch.SF-Bay.ORG> xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) writes:
>walrus@wam.umd.edu (Udo K Schuermann) writes:
>
>> [times to render stuff]
>
>I'm still a bit confused. Are those the times to render a single frame
>of the animation, or to render an entire animation?

Single frames.  Keep in mind that full raytracing is _much_ slower than
Scanline rendering.  My machine traces nearly anything in 30 minutes or
less.

>In either case, how
>many frames of animation did you create, and what was the missing (total
>or frame) time to do the animation?

The Scanline rendered scene came out well, so I went for a "final" with
full trace.  60 frames at 352x470 interlaced HAM, each frame roughly
25 to 35 minutes, takes it a good 30 hours to trace.

>but one of the joys of multitasking is to put something like this
>in the background and let it grind while you put your system to other
>uses. The limiting quantity here seems to be chip ram, so the obvious
>question: is it possible to render to fast ram, or better, directly to a
>file, to prevent a squeeze in chip ram over the long period of an
>animation? Is it possible to checkpoint and restart an animation to
>avoid a restart from scratch due to power problems or system guru's
>during software development?

I always have Imagine running at priority -1 so that the system responds
well when *I* want it to respond.  Imagine just gets all the left-over
cycles.
	No (or very little) chip RAM is used during rendering, and the
frames are written directly to disk.  Chip RAM is used when the
animation is created.  Thus, I render an animation's frames, store
them all on disk (this requires disk space, of course) and when the
whole thing is ready, I'll create the animation without killing the
rendered frames (in case of trouble).  Once that's done, I can wipe
the frames.
	This approach means that when the machine does go down I lose
only a minimal amount of work:  Never more than one (incompletely)
rendered frame, and Imagine updates the project status immediately to
reflect the presence of a new rendered frame.
	It goes to say here that I don't create an animation unless all
the animation's frames have already been rendered.  This way I kill as
little Chip RAM as possible.
	The size of individual frames can range anywhere from 20K to
140K -- depends on the output format as well as the size and complexity
of the scene.

>These are some of the features that would make such a system "fully
>professional".

I agree.  Imagine _is_ professional.

 ._.  Udo Schuermann        "How is American beer similar to making love in
 ( )  walrus@wam.umd.edu    a canoe?" -- "Both are f***ing close to water."