TweetFollow Us on Twitter

TML Pascal Tricks
Volume Number:6
Issue Number:3
Column Tag:Pascal Procedures

TML Pascal Tricks

By Paul Diegenbach, Amsterdam, the Netherlands

XCMD - drawing in a Hypercard stack

The attractiveness of Hypercard is for a large part due to it graphical possibilities. Nice cards always mean nice graphics. The Hypertalk language allows drawing on the screen under program control. When we tear the tools menu off the menubar, we can actually see the actions as the tools flop from pen to brush to marquee and so on. Nice to watch, but oh so slow. Ever tried to draw a complicated graph in Hypercard? I tried it in an attempt to simulate the differentiation of an egg to all the different cells an embryo consists of. One of the theories implies the evaluation of some differential equations and then drawing a thousand points on the screen.

The idea was to let students be able to change the parameters in the equations and see the results in a user-friendly environment. The first step was to implement the equation solving in Hypertalk. Too slow, so an XCMD was quickly written. Drawing the results by Hypertalk: still to slow, so why not do the drawing in the XCMD as well? In a first result the drawing looks nice, but as soon as Hypercard updates the screen from its offscreen bitmap, the drawing disappears. The solution to this problem is to copy the drawing in the paste buffer (scrap) and paste it into Hypercard using the paste command from the menu. This combination works fine and quick. The skeleton for the XCMD is given below, in TML-Pascal, with a Fourier-demo in the drawing part to make it less dumb. In this demo we use parameters from Hypercard for the size of the rectangle and for the Fourier coefficients. Although not necessary, it is often handy to give the rectangle parameters. They can easily be estimated by having a temporary field of the same size and asking in the message window ‘put the size of card field tmp into msg’. The Hypercard stack with this demo implemented is on the source disk for this month.

To avoid flicker between the copy and paste, it is convenient to lock the screen before the XCMD is used. Users of other Pascals sometimes need to remove the ParamPtr parameter, that is the first parameter in every call to the glue routines:

{1}

UNIT PictToScrp;
(******************************************************      
This XCMD demodnstrates a method to plot and calculate in Pascal (perhaps 
with floating point processor enabled) and then copy and paste the picture 
in the card compile and link as follows (assuming Fourier is an existing 
stack):
  
  TMLPascal Fourier.p
or:  ( really fast on a mac II)
  TMLPascal Fourier.p  -MC68020 -MC68881 -d Elems881=true

  Link -w -t ‘STAK’ -c ‘WILD’ 
  -m FOURIER -rt XCMD=1282 -sg Fourier 
   Fourier.p.o 
   “{Libraries}”Runtime.o 
   “{Libraries}”Interface.o 
   “{TMLPLibraries}”TMLPasLib.o 
   “{Libraries}”HyperXLib.o 
   -o “Fourier”

 Hypercard call :
  set the lockscreen to true
  -- prevents flicker
  Fourier  330,14,480,319,10,7,5,3,4
  -- 330,14,480 is the area to draw into
  -- 10,7,5,3,4  are the fourier factors times 10
  set the lockscreen to false
 ******************************************************)

INTERFACE

  USES MemTypes, QuickDraw, OSIntf, ToolIntf, PackIntf, PasLibIntf, HyperXCMD;

  PROCEDURE Fourier(ParamPtr: XCMDPtr);

IMPLEMENTATION

  PROCEDURE PictScrap(ParamPtr: XCMDPtr); FORWARD;

  PROCEDURE Fourier(ParamPtr: XCMDPtr);
    BEGIN
      PictScrap(ParamPtr);
    END;

  PROCEDURE PictScrap(ParamPtr: XCMDPtr);
    VAR
      thePoint     : Point;
      hPicture     : PicHandle;
      rg           : rect;
      Piclength    : LONGINT;
      xoffset, yoffset: integer;
      str          : str255;
      xLeft, bot, top, xRight: LONGINT;
      one, two, three, four, five: LONGINT;
      x, y         : extended;
      z1, z2, z3, z4, z5: extended;

PROCEDURE MyDrawing;
 { all your drawing stuff goes here }
      VAR
        i            : integer;
        maxim, offset: extended;

      FUNCTION Sinus(x: extended): extended;
        BEGIN
          Sinus := sin(x) * z1 + sin(2 * x) * z2 + sin(3 * x) * z3 + 
sin(4 * x)  * z4 + sin(5 * x) * z5
 { the more, the better }
        END;

      BEGIN
        eraserect(rg);
        Framerect(rg); { optional }
        offset := top + (bot - top) / 2.0;
        z1 := one / 10.0;
        z2 := two / 10.0;
        z3 := three / 10.0;
        z4 := four / 10.0;
        z5 := five / 10.0;
        x := 0.02 {1 / 50} ;
        maxim := Sinus(x);
        FOR i := 2 TO 314 DO
          BEGIN
          IF i MOD 10 = 0 THEN
SendCardMessage(ParamPtr, ‘set cursor to busy’);
          x := i / 50;
          y := Sinus(x);
          IF maxim < y THEN
            maxim := y;
          END;

        x := 1 / 50;
        y := Sinus(x);
        maxim := 100 / maxim;
SendCardMessage(ParamPtr, ‘set cursor to busy’);
        moveto(xLeft + 1, round(y * maxim + offset));
        FOR i := 2 TO 314 DO
          BEGIN { for two pi }
          x := i / 50;
          y := Sinus(x);
lineto(i + xLeft + 1, round(y * maxim + offset))
          END;
SendCardMessage(ParamPtr, ‘set cursor to busy’);
        penpat(ltgray);
        moveto(xLeft + 1, round(offset));
        lineto(xRight - 2, round(offset));
        pennormal
      END;

    FUNCTION GetParameter(n: integer): LONGINT;
      VAR
        tmp          : LONGINT;
      BEGIN
        ZeroToPas(ParamPtr, ParamPtr^.params[n]^, str);
        stringToNum(str, tmp);
        GetParameter := tmp
      END;

    BEGIN
      IF ParamPtr^.paramCount <> 9 THEN
        SendCardMessage(ParamPtr, ‘put “wrong number of parameters” into 
msg’)
{ I think a more convenient way of error report than by ParamPtr^.ReturnValue 
}
      ELSE
        BEGIN
{get the drawing rectangle coordinates from hypercard }
        xLeft := GetParameter(1);
        top := GetParameter(2);
        xRight := GetParameter(3);
        bot := GetParameter(4);

{ In this example : get Fourier coëfficients from hypercard }
        one := GetParameter(5);
        two := GetParameter(6);
        three := GetParameter(7);
        four := GetParameter(8);
        five := GetParameter(9);
        setrect(rg, xLeft, top, xRight, bot);
        xoffset := xLeft + 5;
        yoffset := top + 5;
        cliprect(rg);
        hPicture := OpenPicture(rg);
        Showpen;
        MyDrawing; { here all your drawing }
        closepicture;
        Piclength := GethandleSize(handle(hPicture));
        IF ZeroScrap + putscrap(Piclength, ‘PICT’, ptr(hPicture^)) = 
NoErr THEN
     ParamPtr^.ReturnValue := PasToZero(ParamPtr, ‘’)
        ELSE
          ParamPtr^.ReturnValue := PasToZero(ParamPtr, ‘something wrong’);
SendCardMessage(ParamPtr, ‘choose select tool’);
SendCardMessage(ParamPtr, ‘domenu “Paste Picture”’);
SendCardMessage(ParamPtr, ‘choose browse tool’);
        END
    END;
END.

Small and Dirty “Write Always”

In the debugging of large programs we were accustomed to put a lot of ‘writeln’s’ in the source text to show what was happening. Although a workable solution on mainframes and mini’s, that’s not so easy in the Macintosh environment, there is not always a window available to write in. The following small subroutine (TML Pascal version) does the trick with some disadvantage: it overwrite all its lines on top of each other at the bottom of the screen in some kind of status line (bit like Online companion), but, sorry, the line is not automatically removed after leaving the program. Dirty isn’t it, so surely for debugging only. An ‘invalrect’ after each multifinder event and at the end of the program is sometimes a solution.

In the program source you write something like :

--2

 if dbg then DQText(‘now in procedure blahblah’)

(The clever one’s can write a MPW-script to put it after the first begin in every procedure or function) Dbg is used as a constant (or in a compiler directive).

The procedure (as a Pascal unit) looks like :

{3}

UNIT DQTextProcedure;
  INTERFACE
    USES
MemTypes, QuickDraw, OSIntf, ToolIntf, PackIntf, QDaccess;
 
{ Tml pascals QDaccess defines:
 TYPE  QDGlobalsPtr = ^QDGlobalsRec;
    QDGlobalsRec =
      record
        randSeed   :  LongInt;
        screenBits :  BitMap;
        arrow      :  Cursor;
        dkGray     :  Pattern;
        ltGray     :  Pattern;
        gray       :  Pattern;
        black      :  Pattern;
        white      :  Pattern;
        ThePort    :  GrafPtr;
      end;
function QDGlobals: QDGlobalsPtr;external;}

PROCEDURE DQText(Message: Str255);
  IMPLEMENTATION
PROCEDURE DQText(Message: Str255);
VAR
  SavedPort    : GrafPtr;
  LocalPort    : GrafPort;
  TheRect      : Rect;
BEGIN
  WITH QDGlobals^ DO
    BEGIN
      GetPort(SavedPort);
      OpenPort(@LocalPort);
      SetPort(@LocalPort);
      WITH ScreenBits.Bounds DO
 { this is QDGlobals^ s ScreenBits ! }
SetRect(TheRect, Left, Bottom-20, Right, Bottom);
      FillRect(TheRect, White);
      MoveTo(TheRect.Left, TheRect.Top);
      LineTo(TheRect.Right, TheRect.Top);
      MoveTo(TheRect.Left+7, TheRect.Bottom-7);
      DrawString(Message);
      ClosePort(@LocalPort);
      SetPort(SavedPort);
   END;
END;
END.

PROGRAM tstDQtext;
  { test the dqtext procedure : }
  USES MemTypes, QuickDraw, OSIntf, ToolIntf, PackIntf,
    PaslibIntf, QDaccess, DQtext;
  (*
  link as :
    Link  -t ‘APPL’ -c ‘????’ 
      DQtext.p.o 
      tstDQtext.p.o 
      “{Libraries}”Runtime.o 
      “{Libraries}”Interface.o 
      “{TMLPLibraries}”TMLPasLib.o 
      -o tstDQtext
  *)
  BEGIN
    textbook(NIL); { TML pascal simple window }
    writeln(‘ see bottom line’);
    writeln(‘ click mouse button’);
    PLFlush(output);
    DQtext(‘before’);
    REPEAT
    UNTIL button;
    DQtext(‘after mouse button’);
    writeln(‘ type return to end program’);
    readln
  END.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Viber 11.9.1 - Send messages and make fr...
Viber lets you send free messages and make free calls to other Viber users, on any device and network, in any country! Viber syncs your contacts, messages and call history with your mobile device, so... Read more
Vallum 3.3.2 - $15.00
Vallum is a little tool that helps you monitor and block apps connections and throttle apps bandwidth. It is able to intercept connections at the application layer, and hold them while you decide... Read more
Microsoft OneNote 16.31 - Free digital n...
OneNote is your very own digital notebook. With OneNote, you can capture that flash of genius, that moment of inspiration, or that list of errands that's too important to forget. Whether you're at... Read more
Apple Pages 8.2.1 - Apple's word pr...
Apple Pages is a powerful word processor that gives you everything you need to create documents that look beautiful. And read beautifully. It lets you work seamlessly between Mac and iOS devices, and... Read more
Numbers 6.2.1 - Apple's spreadsheet...
With Apple Numbers, sophisticated spreadsheets are just the start. The whole sheet is your canvas. Just add dramatic interactive charts, tables, and images that paint a revealing picture of your data... Read more
f.lux 39.9873 - Adjusts the color of you...
f.lux makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day. Ever notice how people texting at night have that eerie blue glow? Or wake... Read more
Deeper 2.5.0 - 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
NTFS 15.5.71 - Provides full read and wr...
NTFS breaks down the barriers between Windows and macOS. Paragon NTFS effectively solves the communication problems between the Mac system and NTFS. Write, edit, copy, move, delete files on NTFS... Read more
MTR 5.3.0.0 - The Mac's oldest and...
MTR (was MacTheRipper)--the Mac's oldest and smartest DVD-backup app. MTR - the complete toolbox, not a one-trick, point-and-click extractor. MTR is intended for making fair-use, backup copies of... Read more
Keynote 9.2.1 - Apple's presentatio...
Easily create gorgeous presentations with the all-new Keynote, featuring powerful yet easy-to-use tools and dazzling effects that will make you a very hard act to follow. The Theme Chooser lets you... Read more

Latest Forum Discussions

See All

Black Desert Mobile gets an official rel...
Pearl Abyss has just announced that its highly-anticipated MMO, Black Desert Mobile, will launch globally for iOS and Android on December 11th. [Read more] | Read more »
Another Eden receives new a episode, cha...
Another Eden, WFS' popular RPG, has received another update that brings new story content to the game alongside a few new heroes to discover. [Read more] | Read more »
Overdox guide - Tips and tricks for begi...
Overdox is a clever battle royale that changes things up by adding MOBA mechanics and melee combat to the mix. This new hybrid game can be quite a bit to take in at first, so we’ve put together a list of tips to help you get a leg up on the... | Read more »
Roterra Extreme - Great Escape is a pers...
Roterra Extreme – Great Escape has been described by developers Dig-It Games as a mini-sequel to their acclaimed title Roterra: Flip the Fairytale. It continues that game's tradition of messing with which way is up, tasking you with solving... | Read more »
Hearthstone: Battlegrounds open beta lau...
Remember earlier this year when auto battlers were the latest hotness? We had Auto Chess, DOTA Underlords, Chess Rush, and more all gunning for our attention. They all had their own reasons to play, but, at least from where I'm standing, most... | Read more »
The House of Da Vinci 2 gets a new gamep...
The House of Da Vinci launched all the way back in 2017. Now, developer Blue Brain Games is gearing up to deliver a second dose of The Room-inspired puzzling. Some fresh details have now emerged, alongside the game's first official trailer. [Read... | Read more »
Shoot 'em up action awaits in Battl...
BattleBrew Productions has just introduced another entry into its award winning, barrelpunk inspired, BattleSky Brigade series. Whilst its previous title BattleSky Brigade TapTap provided fans with idle town building gameplay, this time the... | Read more »
Arcade classic R-Type Dimensions EX blas...
If you're a long time fan of shmups and have been looking for something to play lately, Tozai Games may have just released an ideal game for you on iOS. R-Type Dimensions EX brings the first R-Type and its sequel to iOS devices. [Read more] | Read more »
Intense VR first-person shooter Colonicl...
Our latest VR obsession is Colonicle, an intense VR FPS, recently released on Oculus and Google Play, courtesy of From Fake Eyes and Goboogie Games. It's a pulse-pounding multiplayer shooter which should appeal to genre fanatics and newcomers alike... | Read more »
PUBG Mobile's incoming update bring...
PUGB Mobile's newest Royale Pass season they're calling Fury of the Wasteland arrives tomorrow and with it comes a fair chunk of new content to the game. We'll be seeing a new map, weapon and even a companion system. [Read more] | Read more »

Price Scanner via MacPrices.net

New 2019 16″ MacBook Pros on sale for $100 of...
Apple Authorized Reseller Adorama has new 2019 16″ MacBook Pros on sale today for $100 off Apple’s MSRP, each including free shipping. In addition, Adorama charges sales tax for NY & NJ residents... Read more
Apple Watch Series 3 GPS models on sale for l...
Amazon has Apple Watch Series 3 GPS models on sale starting at only $179. There prices are the lowest we’ve ever seen for these models from any Apple reseller. Choose Amazon as the seller rather than... Read more
iOS Bug In Facebook News Feed Lets Device Ca...
NEWS: 11.15.19- Users of the Facebook social media platform’s mobile app running on iOS devices won’t, like, this piece of news one bit in where a bug in the News Feed gave access to the camera... Read more
16″ MacBook Pros on sale! Preorder at Amazon...
Apple’s new 16″ MacBook Pros were only introduced yesterday, but Amazon is already offering a $100 discount on preorders. Prices for the base 6-Core 16″ MacBook Pros start at $2299: – 2019 16″ 2.6GHz... Read more
Use our exclusive MacBook Price Trackers to f...
Our Apple award-winning MacBook price trackers are the best place to look for the best sales & lowest prices on new and clearance MacBook Airs and MacBook Pros–including Apple’s new 16″ MacBook... Read more
New November Verizon iPhone deal: Get an iPho...
Verizon has the 64GB iPhone Xr on sale for 50% off for a limited time, plus they will include a free $200 prepaid MasterCard and a free Amazon Echo Dot. That reduces their price for the 64GB iPhone... Read more
Apple cuts prices on clearance, refurbished 2...
Apple has clearance 2018 15″ 6-Core Touch Bar MacBook Pros, Certified Refurbished, now available starting at only $1829. Each model features a new outer case, shipping is free, and an Apple 1-year... Read more
Up to $450 price drop on clearance 15″ MacBoo...
B&H Photo has dropped prices Apple’s 2019 15″ 6-Core and 8-Core MacBook Pros by $400-$450 off original MSRP, starting at $1999, with free overnight shipping available to many addresses in the US... Read more
Here’s how to save $200 on Apple’s new 16″ Ma...
Apple has released details of their Education discount associated with the new 2019 16″ 6-Core and 8-Core MacBook Pros. Take $200 off the price of the new 8-Core model (now $2599) and $200 off the 16... Read more
Price drop! 2019 15″ 2.6GHz 6-Core MacBook Pr...
Focus Camera has dropped their price for clearance 2019 15″ 2.6GHz 6-Core Space Gray MacBook Pros by $400 to $1999 shipped. Apple’s original MSRP for this model was $2399. Focus charges sales tax for... Read more

Jobs Board

Best Buy *Apple* Computing Master - Best Bu...
**746655BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Store NUmber or Department:** 002518-Atlantic Center-Store **Job Description:** Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**744973BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Store NUmber or Department:** 000949-Rochester Hills-Store **Job Description:** Read more
AV Systems Engineer at *Apple* - Theorem, L...
Job Summary Apple Retail Technology is looking for an Audio Visual Systems Engineer to design and implement scalable, next-generation A/V solutions for Apple ?s Read more
Nurse Practitioner - Field Based (San Bernard...
Nurse Practitioner - Field Based (San Bernardino, CA, Apple Valley, Hesperia) **Location:** **United States** **New** **Requisition #:** PS30312 **Post Date:** 3 Read more
Best Buy *Apple* Computing Master - Best Bu...
**746510BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Store NUmber or Department:** 001407-Milford-Store **Job Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.