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- Path: sparky!uunet!europa.asd.contel.com!darwin.sura.net!lhc!adm!news
- From: akin@tuolumne.asd.sgi.com (Allen Akin)
- Newsgroups: comp.sys.sgi
- Subject: Re: SGI Phigs implementation
- Message-ID: <34674@adm.brl.mil>
- Date: 14 Dec 92 22:25:16 GMT
- Sender: news@adm.brl.mil
- Lines: 48
-
-
- In article <1407@shrike.com>, flash@austin.lockheed.com writes:
- >
- > ...She said that
- > 1) Phigs is built into X11R5 (true? if so, how about it
- > SGI?)
-
- That's a bit misleading. The PEX sample implementation is available
- from the X Consortium as part of the X11 distribution, and it includes
- a PHIGS API. However, it lacks some fairly important functionality
- (e.g. Z-buffering) and is reported to be quite slow. It needs to be
- ported, extended, and optimized for the target graphics system. Since
- this requires a huge amount of work, not all vendors will be using this
- approach to provide a product-quality PHIGS on their systems.
-
- > 2) Figaro+ (for the SGI) is actually built on top of GL.
- > That I found hard to believe
-
- I believe this is true. Perhaps someone from Liant could comment.
-
- > ...However, I am curious if the SGI implementation of Phigs takes
- > advantage of the CLEARLY SUPERIOR SGI graphics hardware, or is it
- > as crippled as the X server?
-
- To the best of my knowledge, SGI doesn't sell an internally-developed
- PHIGS. However, we do refer people to third-party implementations
- (like Figaro+). I believe most (if not all) of those use GL for
- rendering.
-
- Someone from Liant should speak to the performance characteristics
- of Figaro+.
-
- By the way, is there some performance problem with X that particularly
- bothers you?
-
- > I presume that GL is the SGI answer for really hot graphics
- > performance, but what about OpenGL on other platforms (S*n)? Will
- > it out-perform an X-based application?
-
- Depends on the application, the implementation of OpenGL, and the
- hardware on which they'll be run. For applications that involve 3D
- transformations, lighting, and smooth shading, I'd certainly expect
- OpenGL applications to do better than X applications, unless OpenGL is
- naively layered on X. This would be even more likely on machines with
- more hardware support for those graphics functions.
-
-
- Allen
-