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From: andrey mirtchovski <andrey@lanl.gov>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] vnc[vs] implementation question
Date: Tue, 18 Jun 2002 11:03:56 -0600	[thread overview]
Message-ID: <1766e9b4ce8a1a43a6748a2049e2c87d@acl.lanl.gov> (raw)

> it's worth noting that vncs is what uses
> the stand-ins for devdraw etc.
>
> vncv doesn't.  vncv probably has good performance
> just because all it does is write blocks to the
> screen.  memmove to the screen is fast.

got it...  the trick (or rather, the problem with xaos) is that it
does
	loadimage(someimage, buffer, ...);
	draw(screen, someimage,...);

in vncv you (I assume) just do a
	loadimage(screen, buffer, ...);

in XaoS' case, unfortunately, one can't use this approach, because the
pixels are written by the program in CMAP8 format (and the image used
in loadimage(); is alloc-ed in CMAP8 too) and if the screen is
anything else loadimage(screen, ...); fails...

it'd be great to have routines that convert between format en masse
(similar to the ones in color(2)), but that's just as expensive as
doing a loadimage();draw() combination.

or maybe there's a trick to it?



             reply	other threads:[~2002-06-18 17:03 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-06-18 17:03 andrey mirtchovski [this message]
  -- strict thread matches above, loose matches on Subject: below --
2002-06-18 17:48 andrey mirtchovski
2002-06-18 17:14 Russ Cox
2002-06-18 16:00 Russ Cox
2002-06-18 15:54 andrey mirtchovski
2002-06-18 15:51 Russ Cox
2002-06-18 15:43 andrey mirtchovski

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