Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!tut.cis.ohio-state.edu!cwjcc!hal!nic.MR.NET!umn-cs!berlin!grg
From: grg@berlin.acss.umn.edu (George Gonzalez)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Text Drawing at speeds in excess of 1200baud
Summary: Dont use drawchar
Keywords: help, software, terminal, DrawChar, QuickDraw, ack
Message-ID: <281@berlin.acss.umn.edu>
Date: 15 Jan 89 05:42:58 GMT
References: <2220@uokmax.UUCP>
Organization: U of M MicroGroup, Minneapolis
Lines: 14


Here's how to speed up your serial I/O to screen.  I wish Red Ryder and
Microphone were listening.

(1)  Don't use drawchar.  There's too much overhead in drawing 1 char at a time.Try gathering 5-20 chars at a time and then drawing them all at once with
DrawText or DrawString.  This should help a lot.  You'll need to special
case the processing of control characters and escape sequences though.  You'll
also need a timeout to flush the last 5-20 characters.  A bit messy but this
is the only way you can go above 1200 baud on a plain Mac.

(2) You then may find the bottleneck is in scrolling the screen.  You can
speed this up by scrolling up several lines at a time.  This is somewhat ugly
but at 9600 baud the eye can barely tell if you're scrolling 1 line or 3 lines
at a time.