Printing Techniques 1
|Column Tag:||Basic School
By Dave Kelly, Hybrids Engineer, Hughes Aircraft Co., MacTutor Editorial Board
This month's column features a guide to printing on the Macintosh. The ability of the Macintosh to make our documents look good is one of the things that attracted me to the Mac. There are some choices to make when printing via Microsoft BASIC.
MSBASIC offers the following commands for printing:
BASIC PRINT COMMANDS
LCOPY - Sends a copy of screen to the printer just like command shift-4. (standard quality)
LIST,filename - see below for valid filenames.
LLIST - same as LIST,filename when filename = "LPT1:DIRECT" see more below.
LPOS - gives the position of the print head (not necessarily the physical position).
LPRINT - works just like PRINT except it prints to the printer instead of the screen. Draft quality.
LPRINT USING - works just like PRINT USING except it prints to the printer instead of the screen. Draft quality
OPEN # / CLOSE # - output to printer is specified by the filespec. Used the same as in storing files to a sequential file.
PRINT # - use with OPEN and CLOSE. Same as output to a sequential file.
PRINT # USING - use with OPEN and CLOSE. Same as output to a sequential file.
WIDTH # - used to set the line width size and print-zone parameters (similar to tab stops) for the printer.
WIDTH output-device - same as WIDTH #
WIDTH LPRINT - same as WIDTH #
WINDOW OUTPUT # - allows the printer to print subsequent graphics as determined by subsequent graphics statements such as CIRCLE, PSET, PICTURE, and calls to the Macintosh ROM routines. See sample program.
WRITE # - use with OPEN and CLOSE. Same as output to a sequential file.
The filespec, output-device, or filename may be one of the following:
"LPT1:" - All data written to a file opened to this output-device will be directed to the lineprinter. Prints in standard quality and issues a printer form feed when done. Supports graphics.
"LPT1:DIRECT" - When this is used, BASIC sends data to the printer as ASCII characters. The printer will respond to all normal printer codes just as it would connected to some other computer. Prints draft quality with no form feed. Fastest way to print. No graphics.
"LPT1:PROMPT" - This calls the standard page setup and printer quality dialog boxes and allows you to choose and quality of printing. Also allows 50% reduction if you have the new imagewriter driver installed. There is no known way to print high quality without using this output-device. Perhaps there is a way to call the imagewriter driver directly?? Graphics is supported only when High and Standard quality print is selected.
Now the decision is up to you. MSBASIC supplies the tools to print just about anything that can be printed to the screen. When the file-spec is set to one of the modes that supports graphics, (LPT1: or LPT1:PROMPT) whatever font has been specified with the TEXTFONT and other related commands will appear in the proper font as expected. When printing in draft quality modes, graphics is not supported and the font used is the one built in to the printer. One thing missing is the ability to output high quality printing without having to go through the dialogs. There may be a way to call the imagewriter driver directly to do this, but I haven't discovered how to do that yet.
It should be noted that the TAB and SPC functions may only be used with PRINT and LPRINT. This should not be much of a problem though.
The program below demonstrates how to print graphics created within a MSBASIC program. The "LPT1:PROMPT" output- device specification is used. This allows you to print with any quality of printing. The program uses the PICTURE statement to create a sine wave drawing. The menu lets you print on the screen or the printer or do a screen dump using the LCOPY statement. The WINDOW OUTPUT # statement is used to send graphics output to the printer. The WINDOW OUTPUT # statement saves graphics commands and sends them to the printer when the output file is closed. In this program I have used the ROM functions PAINTOVAL, ERASEOVAL, and FRAMEOVAL to draw a sinewave either on the screen or on the printer. The ROM functions are well documented in the MSBASIC 2.0 manual.
NOTE THAT THIS ROUTINE DOES NOT WORK WITH THE LASER PRINTER. MACTUTOR WILL PAY $50 TO THE FIRST ARTICLE SUBMISSON THAT EITHER MAKES THIS PROGRAM WORK ON THE LASER OR GIVES A WELL DOCUMENTED ACCOUNT OF WHY IT DOESN'T.
The Macintosh BASIC Handbook, by Thomas Blackadar and Jonathan Kamin makes no reference printing graphics on the printer. Apparently Apple has spent alot of time trying to develop MacBASIC as an "educational" tool and hasn't developed all the features to make it into a serious development language. According to this book, and few other "pre-mature" books that are out, the TOOLBOX function will not even be documented in the initial release of MacBASIC. The TOOLBOX includes the means of creating windows, menus, and other Mac controls. Printing is limited to draft quality via a file aparameter named .PRINTER. The fancy features of MacBASIC only apply to the Mac screen.
' Sine Wave
' by Dave Kelly
' ©MACTUTOR 1985
ON MENU GOSUB premenu: MENU ON
WINDOW OUTPUT 1
CLS:PRINT" Please wait while picture data is being recorded (approx
FOR x=10 TO 525
' Sine wave equation
'Set up parameters for PAINTOVAL
'Setup parameters for ERASEOVAL
'Setup parameters for FRAMEOVAL
PICTURE OFF:MENU OFF
MENU 2,0,1,"Print Sine Wave"
MENU 2,1,1,"On Screen"
MENU 2,2,1,"On Printer"
MENU 2,3,1,"Screen Dump"
ON MENU GOSUB menuselect:MENU ON
CLS: PRINT"Make your ^ ^ ^ ^ ^ ^ ^ ^ ^ selection from this
loop: GOTO loop
IF menunumber=1 THEN PICTURE OFF: GOTO quit
IF menunumber =1 THEN quit
IF menunumber<>2 THEN RETURN
'Print graphics on Screen
IF menuitem=1 THEN CLS:GOSUB printpic:RETURN
' Note that LCOPY does not work with
' laser printers. Anybody know why?
IF menuitem=3 THEN CLS:GOSUB printpic:LCOPY:RETURN
'Print graphics on printer
' Note that this does not work with laser
' printers. Anybody know why?
OPEN "LPT1:PROMPT" FOR OUTPUT AS #1
WINDOW OUTPUT #1
MENU 1,0,0:MENU 2,0,0
MENU 1,0,1:MENU 2,0,1