Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!tut.cis.ohio-state.edu!snorkelwacker!bloom-beacon!EXPO.LCS.MIT.EDU!keith
From: keith@EXPO.LCS.MIT.EDU (Keith Packard)
Newsgroups: comp.windows.x
Subject: Re: Purdue Speedups
Message-ID: <9002122217.AA27286@xenon.lcs.mit.edu>
Date: 12 Feb 90 22:17:10 GMT
References: <222@hal.CSS.GOV>
Sender: daemon@athena.mit.edu (Mr Background)
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> I was wondering if the current version of X (X11R4) has
> incorporated the Purdue Speedups Version 2.0 or 2.1 to
> speed up the mfb code.

All of the purdue speedups which produced measurable performance increases
were incorporated into X11R4.  Additional speedups engineered here at MIT
are also included which produce significant performance improvements
for text, copyarea and 0-width lines.

>                    Also, I was told that the folks
> at Purdue were working on a version for the cfb code,
> and I would like to know if this has been completed/
> or included in the source for X11R4.

The CFB code for R4 was written entirely at MIT and provides reasonable (some
would say "pretty darn good") performance for most 8-bit frame buffers.  Some
ideas from the Purdue monochrome speedups were incorporated, but the structure
of the monochrome speedups was not generally useful on an 8-bit display.

Keith Packard
MIT X Consortium