Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!gatech!mcnc!kk
From: kk@mcnc.org (Krzysztof Kozminski)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Meaning of visRgn in offscreen bitmaps + whinings about PrintManager.
Message-ID: <1358@speedy.mcnc.org>
Date: 25 Aug 89 13:11:04 GMT
Reply-To: kk@mcnc.org.UUCP (Krzysztof Kozminski)
Organization: Microelectronics Center of NC; RTP, NC
Lines: 57

[Had to kill references list - rn would give me internal errors - KK]

In article <3906@internal.Apple.COM> parent@apple.com (Sean Parent) writes:
>> [KK, in an earlier article: Why isn't there a CASE in the LW driver to
>>  handle 100%. 50% and 25% scaling of bitmaps efficiently]
>
>The LW driver does not scale the BitMap PostScript does. What would the 
>case statement do?

It would tell the printing engine: "here are bits, stick'em directly into
your image, don't do any extra processing"

>Remember the LaserWriter Driver is written as a general purpose PostScript 
>Driver. It drives the LaserWriter Classic, +, NT, NTX with variouse ROM 
>revisions and the QMS ColorScript, and variouse other PostScript devices. 
>Sometimes it has to talk to the device through a server.

Either the LaserWriter in the System folder, or the software in the
LaserWriter hardware knows the actual physical resolution of the device
(I suspect both do). I see no reason why this knowledge should not be
used to speed up bitmap printing. Probably the PostScript software in the
LW (hardware) should be smart enough to notice that the dimension of the
bitmap is exactly the same as it destination rectangle.

>No, the hex data is twice the size of binary data.

OOPS, my error.

>Yes, it [printing a full page bitmap - KK] should take only 3 seconds. Or
>even 6 seconds sent as HexData. But 
>there is overhead in packaging the data, overhead in sending it (can you 
>say busy networks and protocall layers), then PostScript gets
>its grubby little hands on it and takes a merry amount of time :-P

Yes, like additional 2 minutes.  And I have a single Mac connected to a
single LW, with no other business on the network than transmitting my
bitmap.  So what causes a 2000% time overhead?

>> [A simple method of doing patOr on LW for rectangles]
>Well, that would work fine for rectangles but what about Ovals Arcs, 
>RoundRect, Polygons? (...)
>There is nothing so complicated about it. In fact, the fastest thing would 
>be to image the entire page with QuickDraw and send one big BitMap to your 
>device.

And that's what I wind up doing anyway, unless somebody can tell me how to
emulate patOr more efficiently.
I can see the problems on the QuickDraw - PostScript interface, but
sloooooooooooooooooooow copying bitmaps should not be one of them.

On a side: what is so complicated about rotating bitmaps that QuickDraw
does not have a routine to do it ? How about drawing text vertically?

KK
-- 
Kris Kozminski   kk@mcnc.org
"The party was a masquerade; the guests were all wearing their faces."