Re: [MiNT] XaAES / GEM memory issues

[joska@nvg.org (Jo Even Skarstein)]

On Wed, 10 Jan 2001 17:11:47 +0100, Sven Karlsson wrote:

> All efficient window systems I know of sends redraw messages to the
> connected clients/applications whatever that force them to redraw only a
> piece of the screen, i.e., the visible part of one of their windows.

Actually, the AES doesn't do this. It simply sends the dirty area to all
applications which might be affected by this, i.e. all applications that
has open windows which intersects with it. It's up to the application
to intersect this dirty rectangle with the rectangle list for the
(possibly) affected window.

Ofcourse, if the AES did this check it would reduce the number of
redraw-events a lot, and it wouldn't cause any compatibility problems
either.

I don't think it's strictly necessary to handle clipping in the driver,
but since it naturally must manage the windows it's the obvious place
to do it. Performance could be a problem though, as Konrad pointed out
this happens inside the kernel so it can't be preempted.

/*
** Jo Even Skarstein    http://home.nvg.org/~joska/
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