Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!usc!rutgers!cbmvax!spence
From: spence@cbmvax.commodore.com (Spencer Shanson)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: 3D stuff & quick line drawing
Message-ID: <20884@cbmvax.commodore.com>
Date: 23 Apr 91 15:49:38 GMT
References: <1991Apr21.081925.4722@lynx.CS.ORST.EDU> <1991Apr22.122442.25505@cs.umu.se>
Reply-To: spence@cbmvax.commodore.com (Spencer Shanson)
Organization: Commodore, West Chester, PA
Lines: 33



In article <1991Apr22.122442.25505@cs.umu.se> dvljrt@cs.umu.se (Joakim Rosqvist) writes:
> [stuff deleted]
>Here is a part of the source i use when i want *fast* lines.
>It uses the blitter and writes directly to the DFF regs
>(no flames please, i *did* call Ownblitter first)

Great! But you also need to WaitBlit() after owning the blitter (just to be 
safe), and just before starting to write to any of the blitter registers.

>[stuff deleted]
>	jsr	OwnBlitter(a6)
>	
>	lea	$dff000,a6

** You need to WaitBlit() here

>	move	#$8000,BLTADAT(a6)
> [more stuff deleted]
>wait:	btst	#6,DMACONR(a6)
>	bne.s	wait

** Better to use WaitBlit(), which knows about various Agnus hardware bugs
** (see Autodocs for more details)

-- 
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Spencer Shanson - Amiga Software Engineer     | email: spence@commodore.COM
                                              | or uunet!cbmvax!spence
All opinions expressed are my own, and do not | "You know my methods. Apply
(necessarily) represent those of Commodore.   | them" -- Sir Arthur Conan
                                              | Doyle - 'The Sign of Four'