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From: David Brown <david.brown@hesbynett.no>
Newsgroups: comp.arch
Subject: Re: Is Intel exceptionally unsuccessful as an architecture designer?
Date: Fri, 20 Sep 2024 09:14:12 +0200
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On 20/09/2024 01:40, Lawrence D'Oliveiro wrote:
> On Thu, 19 Sep 2024 12:54:23 +0200, Terje Mathisen wrote:
> 
>> The way I implemented it was by updating the "official" back frame
>> buffer, and compare the update with the visible front buffer. If at any
>> time a write to the back buffer did not result in something that was
>> already in the front buffer, I just copied the back buffer to the front
>> and went on from there.
> 
> Is this where the need for “triple buffering” comes from -- the fact that
> you need to copy the entire contents of one buffer to another?
> 
> The way I understood to do flicker-free drawing was with just two buffers
> -- “double buffering”. And rather than swap the buffer contents, you just
> swapped the pointers to them.

You use triple buffering if the incoming data (or drawing commands, or 
whatever) and the outgoing data (such as to a screen) are asynchronous. 
If you have control of the timing and synchronisation on one side, you 
can get away with double buffering.

You don't usually copy the data in such systems - you just swap pointers 
to the buffer used for the different purposes.