TweetFollow Us on Twitter

4D Graphics
Volume Number:7
Issue Number:2
Column Tag:Database Corner

Related Info: Quickdraw

4th Dimension Graphics

By Haven C. Sweet, Orlando, FL

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Graphics Output in Fourth Dimension.

Haven Sweet is a Professor of Biology at the University of Central Florida. He has been interested in using the Macintosh for a variety of educational purposes, and has tried to incorporate the computer into an academic laboratory setting. He has developed several classroom exercises using 4th Dimension.

Introduction

Although Fourth Dimension (4D) is not a programming language, I prefer to use it for most of my projects since it vastly simplifies programming and managing complex data. However, I recently discovered a very unfortunate limitation of Fourth Dimension; it is unable to draw on the screen using tool box calls.

The Problem

After creating a large data base of organisms with 4D, I added calculations for a cluster analysis to elucidate their possible relationships. When I wanted to present the final results in a dendrogram (Figure 1), I discovered there was no simple mechanism for drawing on the screen or printing text at variable locations.

Figure 1. A sample clustering output, showing the similarity of four different records in the data base. The figure was drawn on an output layout which only contained the buttons.

I would have to write the entire graphics routine in Pascal, compile it as an external procedure, and create external areas within my program. Not being proficient with MPW, I was hesitant to attempt writing anything which would require debugging by switching from MPW to Ext. Mover to 4D to MPW etc. Hoping version 2 would provide direct toolbox routines such as MoveTo(xStart,yStart), LineTo(xEnd,yEnd) and Writeln(Message), I found that Acius had no such plans.

The Solution

Facing the tedium of learning MPW and Pascal, I hit upon a much simpler solution; I created four external units which provide equivalent procedures for moving the pen, drawing a line, writing text at any location on the screen, and defining both pen and text characteristics. Then, using a blank layout screen, I wrote the graphics routines in the layout procedure and invoked these procedures. Although the graphics output is quite slow, it is more than adequate for the occasional presentation of simple data.

The “pseudo toolbox” routines can be as short or long as needed, but each must be compiled separately and given a name different from the toolbox routine. While I toyed with putting a “4D” before the name of every toolbox call, I decided to combine several I need into a single procedure. So, when text must appear at variable locations on the screen, instead of using MoveTo(xStart;yStart); Writeln(message), the new procedure is WriteAt(xStart;yStart;Message). Likewise, when a line must be drawn, instead of using MoveTo and LineTo, they were combined into DrawLine(xStart;yStart;xEnd;yEnd) which defines the start and end of the line. To alter the text or pen’s characteristics, I adopted the syntax used in ZBasic to produce Pen(xSize;ySize;visible;PenMode) and Text(font;point size;mode). Because variables are used, the procedures can use data either stored in the database or generated from it to draw appropriate lines.

These procedures were written in Pascal and compiled as units which can be moved using 4D External Mover into either the resource of a 4D program or the Proc.Ext. The units are quite small, taking under 600 bytes for all four routines. Once installed, the procedures can be called from within the program in the same manner as any global procedure.

The Output Screen

The next problem was to provide a blank screen on which the results could be written, as well as to find the best way to call the function. My solution was to create a dummy data file with all the drawing done in the output layout procedure. However, there must be exactly one record in the file; if the file is empty, the layout screen never appears, while if there are more than one record in the selection, the drawing procedure is executed for each record. Although it is possible to create a set with only one record in it, it is simpler to create a file named “Blank” which contains only one field, “Dummy”. Then, with the User mode, add one record to the file. An empty layout screen must be created for each different graphics screen.

The layout forms in the file “Blank” should have the three markers Header, Detail, and Break positioned at the very top of the page. If no buttons are to appear in the form, the Footer should also should be placed at the top; otherwise, it should be just far enough down to accomidate the buttons (Figure 2).

Figure 2. The appearance of the layout screen on which the drawing or text placement will be done. Note that the markers for Header, Detail and Break are all at the top of the page.

Although other line positions may work (including using the default positioning of the lines), having them at the top is more reliable since unusual things may occur with some positions. For example, if Break or Header are below the window’s margin, nothing will be drawn; if the Detail line is below the window, then the image is drawn and immediately erased; if space remains between the Header and Detail, clicking on the area permits the user to double click the region and jump to the data input mode. Thus, since the user may resize the window, it is safest to prevent anomalies by placing the lines at the top.

The Procedures’ Syntax

The drawing procedures should only be executed in the BEFORE phase, and should use the following formats:

Pen([xSize] [; [YSize]; [Visible]; [Pen Mode]] )

XSize is the horizontal width of the line in pixels.

YSize is the vertical width of the line in pixels. If omitted or set to zero, the xSize value is used for ySize.

Visible is set to one if the line is to be seen or zero if it is invisible.

Pen Mode uses the following;

0 or 8 Pattern COPY

1 or 9 Pattern OR

2 or 10 Pattern XOR

3 or 11 Pattern BIC

4 or 12 Not pattern COPY

5 or 13 Not pattern OR

6 or 14 Not pattern XOR

7 or 15 Not Pattern BIC

All values are optional. A call to Pen with no parameters resets the normal pen (1 by 1 pixel, visible in the copy mode). Partial parameters may also be used. For example, Pen(3;3;1;8) would produce the same effect as Pen(3) or Pen(3;3)-- that is, a visible pen, 3 by 3 pixels in the copy mode. Although ZBasic also includes the possibility of altering the pen pattern, I did not include it in these routines.

Text( [Font] [; [Point size] ; [Face] ; [Mode]] )

Font codes include;

0 System font

1 Application font

2 New York 20 Times

3 Geneva 21 Helvetica

4 Monaco 22 Courier

5 Venice 23 Symbol

11 Cairo 24 Taliesin

Point size can range from 1 through 127

Face codes are; Mode uses the following;

0 Plain 0 or 8 Pattern COPY

1 Bold 1 or 9 Pattern OR

2 Italic 3 or 11 Pattern BIC

4 Underlined 2 or 10 Pattern XOR

8 Outlined 4 or 12 Not pattern COPY

16 Shadow 5 or 13 Not pattern OR

32 Condensed 6 or 14 Not pattern XOR

64 Extended 7 or 15 Not Pattern BIC

Combinations would be the sum of each face; i.e., bold italic text would have a code of 3.

All values are optional; if omitted, the result is 12 point, plain system font in the copy mode. Both Text(22;10;3;0) and Text(22;10;3) define text as 10 point Courier, italic and bold, which is in the COPY mode.

DrawLine( xStart; yStart; xEnd; yEnd)

This procedure draws a line, with the characteristics defined in the Pen procedure, which begins at a point xStart, yStart, and extends to the point xEnd, yEnd. For example DrawLine(1;1;200;1) would draw a line across the top of the screen.

WriteAt( xStart; yStart; Message)

This procedure writes any text stored in Message beginning at a point xStart, yStart. For example, WriteAt(10;YPos;”The results follow”) would print the text 10 pixels from the left edge and YPos pixels from the top.

Example

The following procedures are designed to draw a line on the screen and to place text near its origin. In this example, the coordinates of the line are entered by the user in a dialog box, but they could have been derived from data in the file.

‘ global procedure Draw a line
DEFAULT FILE([Blank])
ALL RECORDS([Blank]) ‘ this file has one record
 ‘ ask for characteristics of line and text
DIALOG(“Dialog box”)
If (OK=1)|(b1=1)
     INPUT LAYOUT(“Blank-line”)
     OUTPUT LAYOUT(“Blank-line”)
     DISPLAY SELECTION(*)
End if 
‘Layout procedure Blank-line
If (Before)
  visible:=1
  PenMode:=8   ‘Pattern copy  
 ‘ pen size entered by user
  Pen (xSize;Ysize;visible;PenMode)
 ‘ start and end positions entered by user
  DrawLine (h1;v1;h2;v2)
 ‘ Face entered by user
  Text (0;12;Face;0) ‘ font,point size,style,mode
  WriteAt ((h1+20);(v1+20);”This is where the line begins.”)
End if 

The Units

The Pascal versions of the four procedures are followed by one annoted example of the MPW commands needed to compile each into a unit. This method of directly creating units was devised by Jud Spencer of After Hours Software, and was distributed by Acius as Technical Note #150, March, 1989.

Unit Pen;
INTERFACE
 USES 
 Memtypes,Quickdraw,OSIntf,Toolintf,packintf;
 Procedure  PenSet(var Xsize,Ysize,visible, Mode: Integer);
IMPLEMENTATION
Procedure PenSet(var Xsize,Ysize,visible, Mode: Integer);
 begin
 PenNormal;
 if (Xsize>0) then
 {its OK}
 else
 Xsize:=1;
 if (Ysize>0) then
 {its OK}
 else
 Ysize:=Xsize;
 PenSize(Xsize,Ysize);
 if (visible=0) then
 HidePen
 else
 ShowPen;
 if (Mode>=0) and (Mode<8) then
 Mode:=Mode+8; {correct if wrong mode range used}
 if (Mode>7) and (Mode<16) then
 PenMode(Mode);
 end;
END.
____________________________________________
Unit DrawLine;
INTERFACE
 USES 
 Memtypes,Quickdraw,OSIntf,Toolintf,packintf;
 
 Procedure DrawALine(var h1,v1,h2,v2: Integer);
 
IMPLEMENTATION
 Procedure DrawALine(var h1,v1,h2,v2: Integer);
 begin
 MoveTo(h1,v1);
 LineTo(h2,v2);
 end;
END.
____________________________________________
Unit Text;
INTERFACE
 USES 
  Memtypes,Quickdraw,OSIntf,Toolintf,packintf;
 Procedure TextSet(var font,point,StyleNum,mode: Integer);
IMPLEMENTATION
 Procedure TextSet(var font,point,StyleNum,mode: Integer);
 begin
 if (font>0) then
 TextFont(font)
 else
 TextFont(0);
 if (point>0) and (point<128) then
 TextSize(point)
 else
 TextSize(12);
 if (mode>7) and (mode<16) then
 mode:=mode-8; {correct if wrong mode range used}
 if (mode>=0) and (mode<8) then
 TextMode(mode) 
 else
 TextMode(0);
 if (StyleNum>0) and (StyleNum<128) then
 TextFace(Style(StyleNum))
 else
 TextFace([]);
 end; {procedure}
END.
____________________________________________
Unit WriteAt;
INTERFACE
 USES 
 Memtypes,Quickdraw,OSIntf,Toolintf,packintf;
 Procedure WriteItAt(var h1,v1:Integer;var s: Str255);   IMPLEMENTATION
 Procedure WriteItAt(var h1,v1:Integer;var s: Str255);
 begin
 MoveTo(h1,v1);
 DrawString(s);
 end;
END.

Workshop Commands

MPW worksheet commands for the WriteAt procedure are described below. Set the correct directory, then replace or correct all the items noted below as each different unit is compiled and linked.

Pascal WriteAt.p
#      Fix ^     Use unit’s name
Link -w -p WriteAt.p.o 
#             Fix ^    Use unit’s name
“{Libraries}”Runtime.o 
“{Libraries}”Interface.o 
“{PLibraries}”PasLib.o 
-m WRITEITAT 
#    Fix ^    use ALL CAPS with the procedure’s name (not the Unit’s)
-rt 4DEX=16114 
#Fix ^ be sure 4D is name of 4th Dimension, or change it here
-sg Main2 
-sn “Main2=WriteAt(&I;&I;&S)” 
#      Fix ^         Fix ^  with proper variable list, where I=integer, 
S=String
-o Proc.Ext(WriteAt)
#          Fix ^      with proper unit name

Conclusions

Although some labor is required to initially write and compile the graphics external procedures, it only needs to be done once. After being installed in the Proc.Ext, a 4th Dimension database can access the procedures with minimal effort. Unfortunately, describing the process makes it sound much more difficult than it actually is.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

BetterTouchTool 2.332 - Customize multi-...
BetterTouchTool adds many new, fully customizable gestures to the Magic Mouse, Multi-Touch MacBook trackpad, and Magic Trackpad. These gestures are customizable: Magic Mouse: Pinch in / out (zoom... Read more
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
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

Latest Forum Discussions

See All

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 »
Everything about Hero Academy 2: Part 4...
In this part of our Hero Academy 2 guide, we're going to have a look at some of the tactics you're going to need to learn if you want to rise up the ranks. We're going to start off slow, then get more advanced in the next section. [Read more] | Read more »
All the best games on sale for iPhone an...
Another week has flown by. Sometimes it feels like the only truly unstoppable thing is time. Time will make dust of us all. But before it does, we should probably play as many awesome mobile videogames as we can. Am I right, or am I right? [Read... | 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 »
Everything about Hero Academy 2 - The co...
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 »

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

AppleCare Support Engineer for *Apple* Medi...
# AppleCare Support Engineer for Apple Media Products Job Number: 113222855 Santa Clara Valley, California, United States Posted: 14-Nov-2017 Weekly Hours: 40.00 Read more
QA Automation Engineer, *Apple* Pay - Apple...
# QA Automation Engineer, Apple Pay Job Number: 113202642 Santa Clara Valley, California, United States Posted: 11-Dec-2017 Weekly Hours: 40.00 **Job Summary** At Read more
*Apple* Video Partnerships - Apple (United S...
# Apple Video Partnerships Job Number: 113059126 Santa Clara Valley, California, United States Posted: 15-Nov-2017 Weekly Hours: 40.00 **Job Summary** Partnerships Read more
Sr. Engineering Manager- *Apple* Media Produ...
# Sr. Engineering Manager- Apple Media Products Job Number: 113335268 Santa Clara Valley, California, United States Posted: 17-Jan-2018 Weekly Hours: 40.00 **Job Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.