[comp.graphics] Animation techniques?

hudgens@stat.fsu.edu (Jim Hudgens) (09/07/89)

Hello,

A quick question concerning graphics, and in particular animations.  We
have an 3d volume rendering application running on a graphics
processer called a Graphicon 1700, and are able to get a moderately
complex images (10-30,000 polygons, Gourand shaded, 1280*1024
resolution) to display at perhaps 3-10 seconds per image (using
precomputed polygons).  We need to record them so that they can be
replayed at least 2-5 frames per second, or better.  The application is
currently hosted on a Sun 4/280.  The graphicon outputs RGB and NTSC.

We are currently investigating several options, including:
1) Movie camera driven by RS232, and photographing the screen
after each image is displayed.  This would be high resolution, 
but fairly cumbersome.  I do not know of any specific devices
in this category, but I've heard they exist.  
2) Digital film recorder such as those supplied by Dunn or Matrox.
These are high resolution and expensive.  
3) Analog optical drives.  A fairly expensive piece of equipment
(10-20K$), and fairly poor resolution (600*400).  This would interface
directly to the graphicon (for input), and to a VCR (output).
The frames are captured at slow speed and replayed at high speed.
Frame rates  of perhaps 20 per second.
4) Grab the generated image to disk files, and animation effected by
dumping disk files to the host's screen.  We would need a RGB to NTSC
converter to capture the animation to VCR.  The Sun VIDEO-BOARD
announced this year seems to fit the bill exactly.  Animation frame
rates are unknown.  
5) Capture NTSC output to a VCR, and use video editing
equipment to speed up the frame rate.  This seems questionable at
best, and perhaps really expensive.

I'm wondering what others have done in this area, and was hoping 
I could get some recommendations in terms of products or methods
used in doing animation.  Any information, rumors, or experiences 
would be helpful.

We're leaning towards using disk files to store the images (i.e. as
little specialized equipment as possible), but are uncertain as to
what sort of frame rates we will be able to get.  I've seen a
Panasonic optical disk in action, and it is certainly an interesting
prospect.

Please respond by e-mail to me, and if there is interest, I'll
summarize.   

	Jim Hudgens
	hudgens@ray.met.fsu.edu
	hudgens@nu.cs.fsu.edu