BltBitMap

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#818

From: Bill Warner
Date: Thu, 10 Aug 1989 06:18

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I am copying a portion of a screen by first finding the BitMap structure of the
active screen and then Bliting it wo my own BitMap structure. I have a few
questions:

   (1) Is the function BltBitMap syncronous or asyncronous?   Does it call
       WaitBlit?

   (2) Assuming the screen I am copying is not static, would it be proper to
       call Disable() or  Forbid() ?

   (3) When the OS is writing to the blitter, does it turn off interrupts?

I am afraid of the following:  I call Disable, then BlitBitMap.  But just
before I call Disable, some task starts to use the Blitter.  Now when I call
BlitBitMap it waits for another task to complete its blitter operation (which
will never happen).

                                       Chris

                                       CJC@psuecla (bitnet)

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Message-ID: <89222.021843WTW101@PSUVM>

Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!tut.cis.ohio-state.edu!cica!gatech!psuvax1!psuvm!wtw101

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Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!tut.cis.ohio-state.edu!cica!gatech!psuvax1!psuvm!wtw101
From: WTW101@PSUVM.BITNET (Bill Warner)
Newsgroups: comp.sys.amiga.tech
Subject: BltBitMap
Message-ID: <89222.021843WTW101@PSUVM>
Date: 10 Aug 89 06:18:43 GMT
Organization: Penn State University - Center for Academic Computing
Lines: 20