Subject: Re: Blitting
To: Eduardo E. Horvath eeh@btr.com <eeh@btr.btr.com>
From: Chris Hopps <chopps@emunix.emich.edu>
List: amiga-x
Date: 03/24/1994 00:11:00
> If all rendering is done with the blitter, there is also a need to
> allocate off-screen bitmaps (pixmaps) for the server to be able to
> scribble into, so a user-level chipmem allocator seems necessary.

This is best provided under views as part of the interface when 
blit functions are incorporated.  When someone writes the blitter routines
then we can extend the area that is mapped we can also play games later
with VM..  No user accessable generic chipmem allocator should be needed
I will work against it in every way possible.  If there is no other way
then there is no other way, but right now I don't see a problem with 
doing it through mmap() calls.  This will allow us to have fun with 
VM when and if we want to support that allowing the allocation of more
chip memory than is available.

> What are the ramifications of these functions on other graphic cards?

If any other cards are added to dev/view then they need toeither
1) support the interfaces functions, or 2) dev/view needs to provide 
defaults.

The reason /dev/view doesn't have blitter functions as part of the interface 
is becuase I didn't want to write the defaults for boards that had
none.  I also didn't want to write the vustom chip routines. 


> Eduardo Horvath				eeh@btr.com

Chris.

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