info-mac@uw-beaver (info-mac) (08/09/84)
From: Richard Furuta <Furuta@washington.arpa> Inspired by Ed Pattermann's program to print MacPaint documents on the Imagen laser printer, I spent a day a week or so ago putting together a similar program to print MacPaint documents on the Symbolics LGP-1 laser printer. The resulting program is written in C and was developed on Berkeley Unix, version 4.2 bsd. These programs are available for ftp from SUMEX in <info-mac>. There are two files: maclgp.c and maclgp.l (the man page). Usenet and CSNet people can drop me a line (at Furuta@Washington or at uw-beaver!furuta) and I'll mail a copy. By default, the program magnifies the MacPaint document by a factor of 3 resulting in close to life size images. No smoothing of the bitmap is done. There are a couple of interesting points. Unlike the Imagen, the Symbolics laser printer accepts full page bit maps. This has the potential for making the program simpler. However, when one dumps a complete page bit map one ends up with a lot of bytes. At 9600 baud over a RS232 line, this can take up to 8 minutes or so to print one page. Consequently, the program identifies blank scan lines and eliminates them by putting out multiple smaller bitmaps rather than one large bitmap. The Canon LBP-10 print engine used by the LGP-1 seems to be unable to print large dark areas without washing out. The program, by default, "halftones" the output by only printing every other bit (alternating which ones are printed between adjacent scan lines). This sharpens up the output significantly. I'd be interested in hearing about any enhancements or fixes people make to this program. --Rick -------