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From: janjaap@gem.stack.urc.tue.nl (Janjaap van Velthooven)
Newsgroups: comp.sys.amiga.programmer
Subject: depth changing
Message-ID: <146@gem.stack.urc.tue.nl>
Date: 5 Feb 91 16:38:27 GMT
Organization: Stack, Eindhoven University of Technology, The Netherlands
Lines: 37

I receved a request from a certain friend, who can only read but not
post news, to post a certain message. the message follows:

Begin message ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

I am working on a fast fractal program which is programmed following the
guidelines issued by Commodore-Amiga. For greater speed, I'd want to decrease
the number of bitplanes displayed during calculation.
 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.

I couldn't find it in the ROM Kernel Reference Manuals (I think C-A doesn't
like these tricks), so could anyone help me with this ?

Please don't flame me if I posted this wrong or done anything else to offend
you, it's my very first posting.

                                  Thanx !

,--, 
|  |     |                  \     s90406225@hsepm1.hse.nl
+--',--, +-  ,--, +---------->    peter@amice1.stack.urc.tue.nl } won't be for
|   +--' |   +--' |         /     peter@amice2.stack.urc.tue.nl } very long.
`   `--' `-' `--' `

End message ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

I refuse to accept any responsibility for the contents and the effect of
the included message.

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|\  | |  |   |\  |\| |/    +-----------------------------------------------
|\\ | |  |   |\\ | | |     | PAGEFAULT: Wait for wisdom some time.....
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