TweetFollow Us on Twitter

Apr 87 Letters
Volume Number:3
Issue Number:4
Column Tag:Letters

Letters

Postscript Plotting

Philip Baumeister

Loomis, CA

As a new subscriber, let me convey thanks for a great magazine. But as many of your letters seem to contribute information, I seek it. When I write my own plot graphs, I approximate curves the quick and dirty way, with short segments of straight lines. The line itself is drawn at 300 dots/inch on the LaserWriter, but (alas!) the locations of the ends of the line are in pixel coordinates, which means that there are steps, and a resolution of only the nearest 1/72 of an inch in the location of the line. What can I do?

[This may or may not answer your question as you expected, but you might try writing two plot routines; one for the screen in quickdraw, and one for the LaserWriter in Postscript. The following sample program does this. It displays a black box with a plotted line using quickdraw on the screen in Microsoft Basic (see fig. 1). Then it opens a text file and writes a short Postscript program to the file that when downloaded to a LaserWriter, prints the same thing but in Postscript. This way you can plot at the LaserWriter resolution of 300 dots per inch. -Ed]


{1}
REM Basic Postscript Demo
REM  by D. Smith, MS Basic
 CLS
 WINDOW CLOSE 1
MENU
MENU 1,0,0,”File”:FOR i=3 TO 6:MENU i,0,0,””:NEXT i
MENU 3,0,1,”Demo”
MENU 3,1,1,”Draw Line”
MENU 3,2,1,”Quit”
ON MENU GOSUB eventloop:MENU ON
idle:GOTO idle
‘----------------------------------------------------------
eventloop:
MenuStuff=MENU(0)
menuitem=MENU(1)
ON menuitem GOSUB Draw, Quit
RETURN
‘----------------------------------------------------------
Draw:
WINDOW 1,””,(100,75)-(350,150),4
WINDOW OUTPUT 1
GOSUB screendraw
GOSUB Postscript
GOSUB screendraw ‘ update window
MENU
RETURN
‘----------------------------------------------------------
Quit:
CLOSE
WINDOW CLOSE 1
MENU RESET
END
‘----------------------------------------------------------
screendraw:
TEXTFONT(0):TEXTSIZE(12):TEXTFACE(0)
LOCATE 3,10:PRINT “Here is a Basic Line”
LINE (10,10) - (60,60),33,bf
LINE (15,15) - (55,55),30
RETURN
‘----------------------------------------------------------
Postscript:
FIL1$=FILES$(0,”Enter Postscript File ...”):IF FIL1$=”” THEN FIL1$=”LINE.TXT”
 NAM1$=FIL1$
 OPEN NAM1$ FOR OUTPUT AS #1
PRINT #1, “%!PS-Adobe-1.0”
PRINT #1, “%%Title: Postscript Line”
PRINT #1, “%%DocumentFonts: (atend)”
PRINT #1, “%%Creator: Basic”
PRINT #1, “%%CreationDate: 3/1/1987 5:30 PM”
PRINT #1, “%%Pages: (atend)”
PRINT #1, “%%BoundingBox: 0 0 612 792”
PRINT #1, “%%EndComments”
PRINT #1, “%%Document prolog now follows”
PRINT #1, “grestoreall”
PRINT #1, “initgraphics”
PRINT #1, “/pageproc{} def”
PRINT #1, “%%EndProlog”
PRINT #1, “%%Line Example”
PRINT #1, “%%Procedures now follow”

PRINT #1, “/Times-BoldItalic findfont”
PRINT #1, “36 scalefont setfont”

PRINT #1, “/fillbox”
PRINT #1, “{newpath”
PRINT #1, “125 360 moveto”
PRINT #1, “0 72 rlineto”
PRINT #1, “72 0 rlineto”
PRINT #1, “0 -72 rlineto”
PRINT #1, “closepath”
PRINT #1, “0.0 setgray”
PRINT #1, “fill”
PRINT #1, “}def”

PRINT #1, “/box”
PRINT #1, “{newpath”
PRINT #1, “120 355 moveto”
PRINT #1, “0 82 rlineto”
PRINT #1, “400 0 rlineto”
PRINT #1, “0 -82 rlineto”
PRINT #1, “closepath”
PRINT #1, “0.0 setgray”
PRINT #1, “stroke”
PRINT #1, “}def”

PRINT #1, “/line”
PRINT #1, “{newpath”
PRINT #1, “130 427 moveto”
PRINT #1, “192 365 lineto”
PRINT #1, “1.0 setgray”
PRINT #1, “stroke”
PRINT #1, “}def”

PRINT #1, “%% main program”
PRINT #1, “.8 setlinewidth”
PRINT #1, “fillbox”
PRINT #1, “line”
PRINT #1, “210 380 moveto”
PRINT #1, “.7 setgray”
PRINT #1, “(Here is a Basic Line) show”
PRINT #1, “.1 setlinewidth”
PRINT #1, “box”
PRINT #1, “showpage”
PRINT #1, “%% End of Example”
PRINT #1, “%%Trailer”
PRINT #1, “%%Pages:1”
CLOSE #1
RETURN

Fig. 1 Plot a line in Quickdraw & Postscript!

V.I.P. Improves!

Tom Nalevanko

Mainstay, Agoura Hills, CA

Thank you for your coverage of Visual Interactive Programming; V.I.P. users and potential users appreciate the comparitive viewpoint that can only be provided by a multi-language interest publication like MacTutor.

Since the release of V.I.P. in January, we’ve received a number of letters from customers expressing their satisfaction and offering suggestions for improvement. Since we couldn’t answer all of these letters, we did an even better thing. We took the best suggestions and implemented them in a new version 2.1 of V.I.P. This update will be sent, at no charge, to all registered V.I.P. users in March.

The V.I.P. v2.1 update includes the following improvements:

Feature Extensions: Ability to access all fonts, ability to edit Case logic structure, use of window with “grow” box, ability to use “About ...” in apple menu, movement about the flow diagram using arrow keys, use of any ASCII character in a string, etc.

New Intrinsic Functions: err, point, toplft, botrgt, and rect.

New Procedures: draw character, string to scrap, scrap to string, get pen position, set text mode, is real font, get font name, move, line, get picture info, get window title, get active window, undo text, get text, set dlog/alert font and set print options.

Supplementary products that we have announced will be available in April. These include translators to MPW C and Pascal, Lightspeed C and Pascal, and TurboPascal as well as external procedure classes: Speech Manager, Grid Manager, Database Manager, Multi-user Database Manager and the Matrix Manager. [See the VIP article in this issue for a discussion of the LS C translator, which is now functional. -Ed]

MS Basic Compiler Code Expansion

I.N. Botnick

Los Angeles, CA

I’ve been a BASIC programmer for seven years, from the Apple II+ to the IBM PC and finally to the Macintosh. I”ve used IBM Basic I & II, QuickBasic, BetterBasic, True Basic, ZBasic and now MS Basic on the Mac. I want you to know that the Microsoft Basic Compiler for the Macintosh is one of the worse compilers I have ever used. It is unbelievable that a company of Microsoft’s reputation would put out a compiler that is so bad. Take a look at the chart below:

Program ASCII Size Compile Size Memory Use

#1 148K 375K 625K

#2 127K 327K 550K

#3 111K 293K 525K

#4 93K 254K 475K

Each of these programs was designed to run in 330K to 465K of memory, but as you can see, the compiler is generating unusually large code. One main reason is because they are putting 8 bytes in front of each statement for error and event trapping. Program #1 has 8300 statements but only 2550 lines. In all my years of programming, I have never seen a compiler that produced a 375K executable program from a 148K ASCII file! With this version, I still cannot:

1. Run a program from a compiled BASIC program.

2. Read the names of files on a disk and load them into an array.

3. Get the amount of space available on a disk.

4. Create a folder

5. Delete a folder

6. Find the name for a volume without using the FILE$ statement.

7. Set a volume’s name.

8. Find the size of the current screen. (New Macs, remember?)

9. Use color (New Macs?)

10. Init a disk.

11. Get the name of the current printer.

12. Get the name of the file that was clicked to launch the program.

13. Open an included library without a fixed path name (a Macintosh No-No!)

Microsoft Responds

Art Schumer, Program Manager

Microsoft Corp.

As the new Program Manager for Macintosh Languages here at Microsoft, let me thank Dave Kelly for the fine review you wrote in the February issue on our new interpreter and compiler and may I respond to some of the bugs you and your readers have uncovered and which you communicated to me in your recent letter.

Terminal Program: We are actually aware of three seperate problems with the communications port. We are working to fix these problems. We have a patch for one of them.

Default Window: Your right! The display of a default window is annoying in compiled programs. This will be addressed in the next major release.

Zoom Box Support: This will be added to the present method of double-clicking on the title bar in the next major release. Ditto for the compiler.

Large Code Size: We are investigating ways to shrink code size and hopefully will be addressing this in the next major release. It’s not unusual to expect a 3 to 1 expansion in any language from source to compiled form. However, I would like to see it reduced as much as possible. Sharing the runtime module with a number of programs can save 40K.

HFS: Major enhancements to the way HFS is handled in both the interpreter and compiler will be addressed in the next major release.

Undocumented features: TextEdit support was built-in to BASIC at the last minute mainly in response to one of your articles. It was too late to include in the manual but certainly will be documented further in the next revision of the manual. We would like to invite Dave Kelly and Dave Smith to discuss our future plans for MS Basic and to get any suggestions you have as to features you would like to see implemented. [We accept. Ok, gang, here is your chance! Send in your wish list on MS Basic and we will present them to Microsoft. -Ed]

Turbo Bug

Tim Votaw

Anaheim, CA

I stumbled across something recently that I can’t seem to figure out so I thought I’d pass it along to you and your readers. It seems that Turbo Pascal allows division by zero at compilation time and hence produces a nice system crash (ID 4) in your program, although the resume function seems to recover you.

[We checked this error in the latest Turbo Pascal copy, version 1.00D, just sent yesterday to our offices. While this new version is supposed to fix some bugs with the floating point routines, it does not fix this one. Here is the program:


{2}
program divbyzero;
{$U-}
{Turbo Pascal 1.00D version}
uses MemTypes, QuickDraw, OSIntf, ToolIntf, PasInOut, PasConsole;
var
 thenbr,zero:integer;
begin
 zero:=0;
 thenbr:=0 div zero; {this line compiles & executes ok!}
 writeln(thenbr);
 thenbr:=1 div zero; {causes system crash ID=04.}
 writeln(thenbr);
end.

When we ran this program, it compiles and executed! The first division by zero wrote “0” to the window, but the second one produced a system crash with ID 4. When we hit the resume button, Turbo then trapped the error and reported a division by zero error. We then compiled the program to disk and it also produced a nice stand alone application, that when executed, displays a nice system crash although the resume button returns to the Finder. The listing below is the same program in LS Pascal:


{3}
PROGRAM divbyzero;
{LS Pascal Version}
 VAR
 thenbr, zero : integer;
BEGIN
 showtext;{get default text window up}
 zero := 0;
 thenbr := 0 DIV zero; {This line won’t compile!}
 writeln(thenbr);
 thenbr := 1 DIV zero; 
 writeln(thenbr);
END.

We tried the same program in LS Pascal to see what it would do. The program correctly 
refused to compile at the first division by zero statement. We had to change zero to a 1 to 
get the program to compile and execute. Obviously, LS Pascal has better error checking 
at compile time. (See fig. 2) -Ed]

Fig. 2 Catching potential run-time errors
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Live Home 3D Pro 3.2.2 - $69.99
Live Home 3D Pro, a successor of Live Interior 3D, is the powerful yet intuitive home design software that lets you build the house of your dreams right on your Mac. It has every feature of Live Home... Read more
Live Home 3D Pro 3.2.2 - $69.99
Live Home 3D Pro, a successor of Live Interior 3D, is the powerful yet intuitive home design software that lets you build the house of your dreams right on your Mac. It has every feature of Live Home... Read more
FileZilla 3.27.0.1 - Fast and reliable F...
FileZilla (ported from Windows) is a fast and reliable FTP client and server with lots of useful features and an intuitive interface. Version 3.27.0.1: MSW: Add misssing file to .zip binary package... Read more
Spotify 1.0.59.395. - Stream music, crea...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
Sierra Cache Cleaner 11.0.6 - Clear cach...
Sierra Cache Cleaner is an award-winning general purpose tool for macOS X. SCC makes system maintenance simple with an easy point-and-click interface to many macOS X functions. Novice and expert... Read more
DiskCatalogMaker 7.1.2 - Catalog your di...
DiskCatalogMaker is a simple disk management tool which catalogs disks. Simple, light-weight, and fast Finder-like intuitive look and feel Super-fast search algorithm Can compress catalog data for... Read more
Live Home 3D Pro 3.1.2 - $69.99
Live Home 3D Pro, a successor of Live Interior 3D, is the powerful yet intuitive home design software that lets you build the house of your dreams right on your Mac. It has every feature of Live Home... Read more
Deeper 2.2.1 - Enable hidden features in...
Deeper is a personalization utility for macOS which allows you to enable and disable the hidden functions of the Finder, Dock, QuickTime, Safari, iTunes, login window, Spotlight, and many of Apple's... Read more
Pinegrow 3.04 - Mockup and design webpag...
Pinegrow (was Pinegrow Web Designer) is desktop app that lets you mockup and design webpages faster with multi-page editing, CSS and LESS styling, and smart components for Bootstrap, Foundation,... Read more
Deeper 2.2.1 - Enable hidden features in...
Deeper is a personalization utility for macOS which allows you to enable and disable the hidden functions of the Finder, Dock, QuickTime, Safari, iTunes, login window, Spotlight, and many of Apple's... Read more

Latest Forum Discussions

See All

The best deals on the App Store this wee...
There are quite a few truly superb games on sale on the App Store this week. If you haven't played some of these, many of which are true classics, now's the time to jump on the bandwagon. Here are the deals you need to know about. [Read more] | Read more »
Realpolitiks Mobile (Games)
Realpolitiks Mobile 1.0 Device: iOS Universal Category: Games Price: $5.99, Version: 1.0 (iTunes) Description: PLEASE NOTE: The game might not work properly on discontinued 1GB of RAM devices (iPhone 5s, iPhone 6, iPhone 6 Plus, iPad... | Read more »
Layton’s Mystery Journey (Games)
Layton’s Mystery Journey 1.0.0 Device: iOS Universal Category: Games Price: $15.99, Version: 1.0.0 (iTunes) Description: THE MUCH-LOVED LAYTON SERIES IS BACK WITH A 10TH ANNIVERSARY INSTALLMENT! Developed by LEVEL-5, LAYTON’S... | Read more »
Full Throttle Remastered (Games)
Full Throttle Remastered 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Originally released by LucasArts in 1995, Full Throttle is a classic graphic adventure game from industry legend Tim... | Read more »
Stunning shooter Morphite gets a new tra...
Morphite is officially landing on iOS in September. The game looks like the space shooter we've been needing on mobile, and we're going to see if it fits the bill quite shortly. The game's a collaborative effort between Blowfish Studios, We're Five... | Read more »
Layton's Mystery Journey arrives to...
As you might recall, Layton's Mystery Journey is headed to iOS and Android -- tomorrow! To celebrate the impending launch, Level-5's released a new trailer, complete with an adorable hamster. [Read more] | Read more »
Sidewords (Games)
Sidewords 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Grab a cup of coffee and relax with Sidewords. Sidewords is part logic puzzle, part word game, all original. No timers. No... | Read more »
Noodlecake Games' 'Leap On!...
Noodlecake Games is always good for some light-hearted arcade fun, and its latest project, Leap On! could carry on that tradition. It's a bit like high stakes tetherball in a way. Your job is to guide a cute little blob around a series of floating... | Read more »
RuneScape goes mobile later this year
Yes, RuneScape still exists. In fact, it's coming to iOS and Android in just a few short months. Jagex, creators of the hit fantasy MMORPG of yesteryear, is releasing RuneScape Mobile and Old School RuneScape for mobile devices, complete with... | Read more »
Crash of Cars wants you to capture the c...
Crash of Cars is going full on medieval in its latest update, introducing castles and all manner of new cars and skins fresh from the Dark Ages. The update introduces a new castle-themed map (complete with catapults) and a gladiator-style battle... | Read more »

Price Scanner via MacPrices.net

Save or Share
FotoJet Designer, is a simple but powerful new graphic design apps available on both Mac and Windows. With FotoJet Designer’s 900+ templates, thousands of resources, and powerful editing tools you... Read more
Logo Maker Shop iOS App Lets Businesses Get C...
A newly released app is designed to help business owners to get creative with their branding by designing their own logos. With more than 1,000 editable templates, Logo Maker Shop 1.0 provides the... Read more
Sale! New 15-inch MacBook Pros for up to $150...
Amazon has the new 2017 15″ MacBook Pros on sale for up to $150 off MSRP including free shipping: – 15″ 2.8GHz MacBook Pro Space Gray: $2249 $150 off MSRP – 15″ 2.89Hz MacBook Pro Space Gray: $2779 $... Read more
DEVONthink To Go 2.1.7 For iOS Brings Usabili...
DEVONtechnologies has updated DEVONthink To Go, the iOS companion to DEVONthink for Mac, with enhancements and bug fixes. Version 2.1.7 adds an option to clear the Global Inbox and makes the grid... Read more
15-inch 2.2GHz Retina MacBook Pro, Apple refu...
Apple has Certified Refurbished 2015 15″ 2.2GHz Retina MacBook Pros available for $1699. That’s $300 off MSRP, and it’s the lowest price available for a 15″ MacBook Pro. An Apple one-year warranty is... Read more
13-inch 2.3GHz Silver MacBook Pro on sale for...
B&H Photo has the new 2017 13″ 2.3GHz/256GB Silver MacBook Pro (MPXU2LL/A) on sale for $1399 including free shipping plus NY & NJ sales tax only. Their price is $100 off MSRP. Read more
Apple Tackles Distracted Driving With iOS 11...
One of the most important new features coming in iOS 11 is Do Not Disturb while driving, intended to help drivers stay more focused on the road. With Do Not Disturb while driving, your iPhone can... Read more
iMazing Mini for Mac: Free Automatic and Priv...
Geneva, Switzerland-based indie developer DigiDNA has released iMazing Mini, their free macOS utility designed to automatically back up iOS devices over any local Wi-Fi network. The app offers users... Read more
Clearance 2016 13-inch MacBook Airs, Apple re...
Apple dropped prices recently on Certified Refurbished 2016 13″ MacBook Airs, with models now available starting at $809. An Apple one-year warranty is included with each MacBook, and shipping is... Read more
9.7-inch 2017 iPads available for $299, save...
B&H Photo has 2017 9.7″ 32GB WiFi iPads on sale for $30 off MSRP for a limited time. Shipping is free, and pay sales tax in NY & NJ only: – 32GB iPad WiFi: $299, $30 off Read more

Jobs Board

*Apple* Retail - Multiple Positions - Apple...
SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions - Apple...
SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Senior Payments Architect - *Apple* Pay - A...
Changing the world is all in a day's work at Apple . If you love innovation, here's your chance to make a career of it. You'll work hard. But the job comes with more Read more
Frameworks Engineering Manager, *Apple* Wat...
Frameworks Engineering Manager, Apple Watch Job Number: 41632321 Santa Clara Valley, California, United States Posted: Jun. 15, 2017 Weekly Hours: 40.00 Job Summary Read more
Manager, *Apple* Media Products - Apple Inc...
Job Summary The Apple Media Products Discovery, Fraud and Abuse team is responsible for protecting the integrity of Apple services. As a manager of the team, you Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.