Tearing problem at bigger overlay sizes

[Matthias Hopf]

On Jan 13, 09 18:07:13 +0100, Xavier Bestel wrote:
> On Tue, 2009-01-13 at 17:41 +0100, Matthias Hopf wrote:
> > > tear free. Sometimes the diagonal tear can be seen in one or more (2..4  
> > > segments out of 11) of the 100 line segments. This last point is really 
> > > puzzling, this could indicate the graphics engine is just keeping up 
> > > with the refresh, slightly slower or slightly faster.
> > 
> > Could be a caching issue, pushing out the cache after each block might
> > help.
> 
> Why not just after the last block ?

Because the chip might reorder memory writes, and decide for later
blocks to be pushed out first (or even pushed out to memory w/o changing
the cache). That way you *could* see multiple tearings.

Again, this is a lot of hand waving. Still, it might be an idea.

Matthias

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