From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Z-Buffered Bitmaps
Date:	25 May 2000 09:25:23 GMT
Organization:	Aachen University of Technology (RWTH)
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Alexei A. Frounze <alex DOT fru AT mtu-net DOT ru> wrote:
> You don't really need any Z-buffers. At least Z-buffer is a computer gfx
> term usually used in 3d gfx. 

Usually, but not only there. In the situation the original poster
describes, he *does* need a z buffer. You didn't read the question
completely, I think: he was talking about multiple _concurrent_
threads blitting windows to a common framebuffer. In that case he
cannot z-sort the windows, simply because there's no point in time
when they're all available, so they can be sorted and output.

His situation requires either a z-buffer or a datastructure that
partitions the plane into rectangles or similar areas of common
'depth', which is somewhat equivalent to the 'dirty rectangles'
blitting method for sprites.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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