Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!bcstec!voodoo!zombie
From: zombie@voodoo.UUCP (Mike York)
Newsgroups: comp.sys.sgi
Subject: Re: lines and libraries
Message-ID: <1271@voodoo.UUCP>
Date: 23 Apr 91 19:10:38 GMT
References: <1991Apr17.144853.17441@dsd.es.com> <1991Apr22.163320.8755@odin.corp.sgi.com>
Organization: BoGART To You Buddy, Bellevue, WA
Lines: 34

In article <1991Apr22.163320.8755@odin.corp.sgi.com> kurt@cashew.asd.sgi.com (Kurt Akeley) writes:
>In article <1991Apr17.144853.17441@dsd.es.com>, pmartz@undies.dsd.es.com (Paul Martz) writes:
>|> 1) Is it normal to see move/draw perform better on a Personal Iris GT
>|> than a VGX? I really should be using v3f for VGX machines, right?
>
>Yes, you really should use v3f on GT, GTX, and VGX machines.  The VGX in
>particular cannot parallelize move/draw syntax commands, and therefore
>performs very poorly on them.  The Personal Iris is unfortunately optimized
>for the soon-to-be-obsolete move/draw interface.

Does this mean that our PI's are soon-to-be-obsolete?  

>v3f calls are the future of the Iris Graphics Library.  If you choose to
>take advantage of the performance advantage of move/draw calls on current
>Personal Iris equipment, you should consider writing your code to use
>v3f on all other platforms.

Here's an excerpt from the man page for move on 4D/35 we've got here:

    NOTE
	 move should not be used in new development.  Rather, lines should be
	 drawn using the high-performance v commands, surrounded by calls to
	 bgnline and endline.

We've been following this advice.  All of our production machines are currently
4D/25TG's (considering 4D/35 upgrades).  Should we change back to move/draw
commands, or is there hope for "high-performance v commands" to be high
performance on the PI's?

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