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Xref: sserve comp.os.386bsd.apps:1033 comp.os.linux.misc:10912 Newsgroups: comp.os.386bsd.apps,comp.os.linux.misc Path: sserve!newshost.anu.edu.au!munnari.oz.au!yarrina.connect.com.au!harbinger.cc.monash.edu.au!yeshua.marcam.com!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!pipex!uknet!festival!edcogsci!richard From: richard@cogsci.ed.ac.uk (Richard Tobin) Subject: Re: DOOM for X Message-ID: <CMIGw6.M3w@cogsci.ed.ac.uk> Organization: HCRC, University of Edinburgh References: <hastyCMEw58.FMr@netcom.com> <2lm9ih$6s5@godot.cc.duq.edu> <glen.763349922@paladine> Date: Fri, 11 Mar 1994 17:36:04 GMT Lines: 24 In article <glen.763349922@paladine> glen@paladine.ece.jcu.edu.au (Glen Harris) writes: >>Amancio, what effect, if any, do you think the shared memory extentions of X >>have on graphics performance? > > What it means is that a bitmap in memory is mapped directly over the >screen, so an access to the array is an access to the screen. No, this isn't what it means. At least, not in any extension to X that I've used. It means that a bitmap in the client's address space is mapped into the server's space. So displaying it on the screen simply involves telling the server to copy it from main memory to display memory (doing whatever horrible contortions are required by the revolting design of the PC), rather than transmitting it through a socket to the server, followed by copying it to display memory. > After the mapping is set up, there's no calls to X for the graphics. No, there's still a call for each graphical operation. -- Richard -- Richard Tobin, HCRC, Edinburgh University R.Tobin@ed.ac.uk "Your monkey has got it right, sir." - HHGTTG