Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!mcnc!kk
From: kk@mcnc.org (Krzysztof Kozminski)
Newsgroups: comp.sys.mac.programmer
Subject: Meaning of visRgn in offscreen bitmaps + whinings about PrintManager.
Message-ID: <1342@speedy.mcnc.org>
Date: 22 Aug 89 13:38:15 GMT
References: <22321@andante.UUCP> <30755@ucbvax.BERKELEY.EDU> <34168@apple.Apple.COM> <1336@speedy.mcnc.org> <3733@internal.Apple.COM>
Reply-To: kk@mcnc.org.UUCP (Krzysztof Kozminski)
Organization: Microelectronics Center of NC; RTP, NC
Lines: 52

In article <3733@internal.Apple.COM> parent@apple.com (Sean Parent) writes:
>In article <1336@speedy.mcnc.org> kk@mcnc.org (Krzysztof Kozminski) writes:
>>As far as I can tell, IM is not correct: drawing does get clipped to visRgn.
>>I have fresh a recollection of creating an off-screen bitmap to produce image
>>for printing and doing CopyBits to the printer port just to find out that
>>I was getting 640x480 pixel image ...
>
>Inside Mac is correct. Drawing does not get clipped to visRgn on an off 
>screen Bit/PixMap with one exception. StdBits (not CopyBits) will obey the 
>visRgn.
>
>Sean Parent

Then how come that the following:

	OpenPort(&offBitsPort);

	... initialize it to be exactly the size of a LaserWriter page ...

	SetPort(&offBitsPort);
	FillRect(&offBitsPort.portRect,gray);
	PrOpenPage(ThePrintPort,NULL);
	CopyBits(&offBitsPort.portBits,&ThePrintPort->gPort.portBits
		,&offBitsPort.portRect,&offBitsPort.portRect,srcCopy,NULL);
	PrClosePage(ThePrintPort);

Results in a printout *clipped to visRgn* ?????

Also: how come that doing this CopyBits in chunks < 3.5kBytes (I know, it
isn't really necessary) is THREE times slower than doing it in one huge piece?

Also: how come a page-sized bit map (filled gray) prints on a LW in ~9
seconds at 100% scale, ~50 seconds at 50%, and ~80 sec at 25%?
Shouldn't the ratios be more like 1 : 4 : 16 ?  Why is it so damn slow
anyway ?  I'd think that just dumping a bitmap is the fastest thing
that can be done (is it communications problem or what? Even at 25%,
the LW page is < 1Mbyte - should transfer real fast)

All the above times on a Mac II with 5 Mbytes of RAM and lots of disk space
and LW II NT, with graphics smoothing OFF and precision bitmap alignment ON.

Finally: am I the only person who thinks that saying in the Inside Mac,
vol. 2, something to the effect "you draw to a printing port just as if
it was a screen" just to follow it 3 pages later with making 95% of
really useful QuickDraw calls (transfer modes & region operations)
invalid on a LaserWriter is, well, inconsistent?  Does anybody has a
good method of doing 'patOr' on an LW short of drawing into your own
off-screen port and then CopyBiting it?

KK
-- 
"The party was a masquerade; the guests were all wearing their faces."