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, ‘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  -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’);
END.
```

Community Search:
MacTech Search:

Capture One 11.0.1.40 - RAW workflow sof...
Capture One is a professional RAW converter offering you ultimate image quality with accurate colors and incredible detail from more than 400 high-end cameras -- straight out of the box. It offers... Read more
GraphicConverter 10.5.4 - \$39.95
GraphicConverter is an all-purpose image-editing program that can import 200 different graphic-based formats, edit the image, and export it to any of 80 available file formats. The high-end editing... Read more
Dash 4.1.3 - Instant search and offline...
Dash is an API documentation browser and code snippet manager. Dash helps you store snippets of code, as well as instantly search and browse documentation for almost any API you might use (for a full... Read more
Microsoft OneNote 16.9 - Free digital no...
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
DEVONthink Pro 2.9.17 - Knowledge base,...
Save 10% with our exclusive coupon code: MACUPDATE10 DEVONthink Pro is your essential assistant for today's world, where almost everything is digital. From shopping receipts to important research... Read more
OmniGraffle 7.6 - Create diagrams, flow...
OmniGraffle helps you draw beautiful diagrams, family trees, flow charts, org charts, layouts, and (mathematically speaking) any other directed or non-directed graphs. We've had people use Graffle to... Read more
iFinance 4.3.7 - Comprehensively manage...
iFinance allows you to keep track of your income and spending -- from your lunchbreak coffee to your new car -- in the most convenient and fastest way. Clearly arranged transaction lists of all your... Read more
Opera 50.0.2762.58 - High-performance We...
Opera is a fast and secure browser trusted by millions of users. With the intuitive interface, Speed Dial and visual bookmarks for organizing favorite sites, news feature with fresh, relevant content... Read more
Microsoft Office 2016 16.9 - Popular pro...
Microsoft Office 2016 - Unmistakably Office, designed for Mac. The new versions of Word, Excel, PowerPoint, Outlook and OneNote provide the best of both worlds for Mac users - the familiar Office... Read more
SoftRAID 5.6.4 - High-quality RAID manag...
SoftRAID allows you to create and manage disk arrays to increase performance and reliability. SoftRAID allows the user to create and manage RAID 4 and 5 volumes, RAID 1+0, and RAID 1 (Mirror) and... Read more

## Latest Forum Discussions

Around the Empire: What have you missed...
Around this time every week we're going to have a look at the comings and goings on the other sites in Steel Media's pocket-gaming empire. We'll round up the very best content you might have missed, so you're always going to be up to date with the... | Read more »
The 7 best games that came out for iPhon...
Well, it's that time of the week. You know what I mean. You know exactly what I mean. It's the time of the week when we take a look at the best games that have landed on the App Store over the past seven days. And there are some real doozies here... | Read more »
Popular MMO Strategy game Lords Mobile i...
Delve into the crowded halls of the Play Store and you’ll find mobile fantasy strategy MMOs-a-plenty. One that’s kicking off the new year in style however is IGG’s Lords Mobile, which has beaten out the fierce competition to receive Google Play’s... | Read more »
Blocky Racing is a funky and fresh new k...
Blocky Racing has zoomed onto the App Store and Google Play this week, bringing with it plenty of classic kart racing shenanigans that will take you straight back to your childhood. If you’ve found yourself hooked on games like Mario Kart or Crash... | Read more »
Cytus II (Games)
Cytus II 1.0.1 Device: iOS Universal Category: Games Price: \$1.99, Version: 1.0.1 (iTunes) Description: "Cytus II" is a music rhythm game created by Rayark Games. It's our fourth rhythm game title, following the footsteps of three... | Read more »
JYDGE (Games)
JYDGE 1.0.0 Device: iOS Universal Category: Games Price: \$4.99, Version: 1.0.0 (iTunes) Description: Build your JYDGE. Enter Edenbyrg. Get out alive. JYDGE is a lawful but awful roguehate top-down shooter where you get to build your... | Read more »
Tako Bubble guide - Tips and Tricks to S...
Tako Bubble is a pretty simple and fun puzzler, but the game can get downright devious with its puzzle design. If you insist on not paying for the game and want to manage your lives appropriately, check out these tips so you can avoid getting... | Read more »
It's fair to say we've spent a good deal of time on Hero Academy 2. So much so, that we think we're probably in a really good place to give you some advice about how to get the most out of the game. And in this guide, that's exactly what you're... | Read more »
In the third part of our Hero Academy 2 guide we're going to take a look at the different modes you can play in the game. We'll explain what you need to do in each of them, and tell you why it's important that you do. [Read more] | Read more »
In this second part of our guide to Hero Academy 2, we're going to have a look at the different card types that you're going to be using in the game. We'll split them up into different sections too, to make sure you're getting the most information... | Read more »

## Price Scanner via MacPrices.net

Deals on clearance 15″ Apple MacBook Pros wit...
B&H Photo has clearance 2016 15″ MacBook Pros available for up to \$800 off original MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: – 15″ 2.7GHz Touch Bar MacBook Pro... Read more
Apple restocked Certified Refurbished 13″ Mac...
Apple has restocked a full line of Certified Refurbished 2017 13″ MacBook Airs starting at \$849. An Apple one-year warranty is included with each MacBook, and shipping is free: – 13″ 1.8GHz/8GB/128GB... Read more
How to find the lowest prices on 2017 Apple M...
Apple has Certified Refurbished 13″ and 15″ 2017 MacBook Pros available for \$200 to \$420 off the cost of new models. Apple’s refurbished prices are the lowest available for each model from any... Read more
The lowest prices anywhere on Apple 12″ MacBo...
Apple has Certified Refurbished 2017 12″ Retina MacBooks available for \$200-\$240 off the cost of new models. Apple will include a standard one-year warranty with each MacBook, and shipping is free.... Read more
Apple now offering a full line of Certified R...
Apple is now offering Certified Refurbished 2017 10″ and 12″ iPad Pros for \$100-\$190 off MSRP, depending on the model. An Apple one-year warranty is included with each model, and shipping is free: –... Read more
27″ iMacs on sale for \$100-\$130 off MSRP, pay...
B&H Photo has 27″ iMacs on sale for \$100-\$130 off MSRP. Shipping is free, and B&H charges sales tax for NY & NJ residents only: – 27″ 3.8GHz iMac (MNED2LL/A): \$2199 \$100 off MSRP – 27″ 3.... Read more
2.8GHz Mac mini on sale for \$899, \$100 off MS...
B&H Photo has the 2.8GHz Mac mini (model number MGEQ2LL/A) on sale for \$899 including free shipping plus NY & NJ sales tax only. Their price is \$100 off MSRP. Read more
Apple offers Certified Refurbished iPad minis...
Apple has Certified Refurbished 128GB iPad minis available today for \$339 including free shipping. Apple’s standard one-year warranty is included. Their price is \$60 off MSRP. Read more
Amazon offers 13″ 256GB MacBook Air for \$1049...
Amazon has the 13″ 1.8GHz/256B #Apple #MacBook Air on sale today for \$150 off MSRP including free shipping: – 13″ 1.8GHz/256GB MacBook Air (MQD42LL/A): \$1049.99, \$150 off MSRP Read more
9.7-inch 2017 WiFi iPads on sale starting at...
B&H Photo has 9.7″ 2017 WiFi #Apple #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 – 128GB iPad WiFi... Read more

## Jobs Board

*Apple* Data Center Site Selection and Strat...
# Apple Data Center Site Selection and Strategy Research Analyst Job Number: 83708609 Santa Clara Valley, California, United States Posted: 18-Jan-2018 Weekly Hours: Read more
Security Engineering Coordinator, *Apple* R...
# Security Engineering Coordinator, Apple Retail Job Number: 113237456 Santa Clara Valley, California, United States Posted: 18-Jan-2018 Weekly Hours: 40.00 **Job Read more
Firmware Engineer - *Apple* Accessories - A...
# Firmware Engineer - Apple Accessories Job Number: 113422485 Santa Clara Valley, California, United States Posted: 18-Jan-2018 Weekly Hours: 40.00 **Job Summary** Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Store Leader - Retail District Manag...
Job Description:Job SummaryAs more and more people discover Apple , they visit our retail stores seeking ways to incorporate our products into their lives. It's your Read more