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- To: alleg-developers@xxxxxxxxxx
- Subject: Re: [AD] Mouse drawings
- From: Chris <chris.kcat@xxxxxxxxxx>
- Date: Sat, 27 Aug 2005 21:08:57 -0700
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On Saturday 27 August 2005 08:42 pm, Victor wrote:
> I fear that removing the way to use show_mouse() in memory bitmaps will
> cause serious compatibilities issues and will break older codes.
>
> I normally do:
All of which will cause problems when the timer tries to update the mouse at
the same time that blit tries to read from it. There is no mutex's associated
with memory bitmaps, so you can't gaurantee that multiple operations won't
occur at the same time. It would be better to maanully draw the mouse to the
buffer before blitting it to the screen.
> I think restricting it to video bitmaps only is a really bad idea,
> since there isn't any technical issues to create such restriction.
There are technical issues. There is no way to gaurantee concurrent drawing
operations won't occur with the mouse timer, and memory bitmaps aren't safe
being used from two different threads.