Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!caen!kuhub.cc.ukans.edu!markv
From: markv@kuhub.cc.ukans.edu
Newsgroups: comp.sys.amiga.programmer
Subject: Re: depth changing
Message-ID: <28400.27aee957@kuhub.cc.ukans.edu>
Date: 5 Feb 91 23:20:23 GMT
References: <146@gem.stack.urc.tue.nl>
Organization: University of Kansas Academic Computing Services
Lines: 24

>  I tried it by changing the Depth field of the BitMap structure in the Screen
> structure to 4 (or 2 in HiRes mode), then call MakeScreen and RethinkDisplay.
> This works all fine, except that the program draws in 4 (or 2) bitplanes,
> so the picture contains just 16 (or 4) colors.

Try creating a duplicate BitMap (and RastPort if needed) for the
BitPlanes, then call MakeScreen() etc.  Use the Duplicate Bitmap and
Rastport with the real number of bitplanes for rendering,  when done,
swap things back.

If you really want to free up cycles, call OFF_DISPLAY/ON_DISPLAY and
shut off screen DMA completly.  You can let the user know time if
passing by playing with the pointer image (DISPLAY doesn't effect
sprites which have their own DMA).

-- 
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Mark Gooderum			Only...		\    Good Cheer !!!
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