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From: oster@dewey.soe.berkeley.edu (David Phillip Oster)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Text Drawing at speeds greater than 1200baud
Message-ID: <27572@ucbvax.BERKELEY.EDU>
Date: 18 Jan 89 01:50:35 GMT
References: <2243@uokmax.UUCP>
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: oster@dewey.soe.berkeley.edu.UUCP (David Phillip Oster)
Organization: School of Education, UC-Berkeley
Lines: 20

The ultimate in text drawing speed can be achieved by:
(o) using a custom font, where each character is 7 pixels high, and, say,
9 pixels tall. f there is one pixel of white space between characters,
then each pixel fits in an 8-bit wide cell.

(o) constrain motion and growing of the window, (a la hypercard) so that
the portRect is always on a byte boundary.

(o) if and only if the destination is a 1-bit deep pixmap, completely
visible, the front window, and un-obscured by other windows, than do the
following ultra-fast code. Otherwise, use the DrawText solution you've
already been told about.

(o) use hand-tuned assembly language to move one of our 9x7 characters to
the screen using 9 move.b instructions.
If you are careful with you registers, you can wrap this up into a custom
SuperDrawText

(o) use hand-tuned assembly instructions to scroll the screen using 
loops unrolled into lots of move.l instructions.