TweetFollow Us on Twitter

Resize Objects
Volume Number:7
Issue Number:4
Column Tag:Jörg's Folder

Related Info: Quickdraw

Getting A Handle On Objects

By Jörg Langowski, MacTutor Editorial Board

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

“C++/MacApp - resizing objects”

As promised last month, this time we’ll start adding some code to our MacApp drawing program to change the basic shapes once they’ve been drawn. I have chosen to implement a resize operation; other functions, like changing colors and patterns, manipulating the order of objects, etc., will follow later.

We are going to use an interface similar to MacDraw, where a selected object has a number of small black squares connected with itself that can be used to change its shape. We’ll call them ‘tags’ in the following. Objects that can be circumscribed by a rectangle have eight tags: four on the corners and four on the centers of the edges. Dragging a corner tag will move the two sides of the rectangle adjacent to the corner, while dragging the edge tag will only move the side of the rectangle that contains the tag.

We’ll need code to display the tags, determine whether the mouse was clicked in one of them, and take action (track the mouse) depending on what tag it was clicked in. Of course, all operations should be undoable, but that’s almost implicit in MacApp.

Detecting the mouse click will proceed in two stages: first, we’ll check whether the mouse has been clicked in any one of the eight tags. If so, we’ll create a new command object of class TSizer, which then does the mouse tracking and track feedback. The command object determines where the mouse was clicked exactly, and the tracking and action will depend on the tag.

For the first phase - determining whether the mouse was clicked in one of the tags at all - it is convenient to create a region that consists of all the eight tags. This region is stored in a new instance variable of TBox, fTagRgn, and created when an object is selected and redrawn (see changes to the TBox::DrawShape method in listing 3). Also, the eight tags are stored individually as Rect instance variables.

The changes to the mouse down command handler are shown in listing 2. We shall now create a TSketcher, a TDragger, or a TSizer command object, depending on where the mouse was clicked - outside any object, inside a selected object, or inside one of the tags of a selected object.

In the TSizer::TrackMouse method we determine which of the eight tags was clicked in, and allow for changes in the top, bottom, left and right coordinates of the object (flags pT, pB, pL, pR). While those coordinates are continuously changed in the TrackMove phase of the TrackMouse method, the TrackFeedback method simply redraws the object rectangle in XOR mode. Undoing can be implemented very simply by remembering the old coordinates of the object.

Sounds simple? It is, and again the modifications are only to a very limited part of the total code - one of MacApp’s great advantages. We still have to add one more ‘Buzzword’ to the list of commands that appear after the Undo/Redo menu item (Listing 4), and extend the Make file a little. By now our code has grown too big to fit into one segment (compiling in Debug mode). Thus, you’ll also see how to segment a MacApp program.

I have put the code that is supposed to go into the new segment into the file TBox.cp, containing TSizer and all the Box/Shape classes. We then have to tell the MacApp builder that this file should be linked in under a different segment name. The necessary changes are shown in listing 5. We add the name of the new source file (TBox.cp) to the list of OtherInterfaces, and the corresponding object file (TBox.cp.o) to the list of OtherLinkFiles. Last, we add the dependency rule for generating the object file (also containing a comment line showing the build progress).

The drawing example will certainly still be extended over the next few months, but we’ll also take up some Forth again soon. Until then.

Listing 1: Changes to TEDrag.h

class TBox : public TObject {
 Rect fLocation;
 Rect fTL,fTR,fBL,fBR,
 virtual pascal void IBox(Rect *itsLocation);
 virtual pascal void DrawShape();
 virtual pascal void NeedDiskSpace(long *data);
 virtual pascal void Read(short aRefNum);
 virtual pascal void Write(short aRefNum);
#ifdef qDebug
 virtual pascal void Fields(pascal void (*DoToField) 
 (StringPtr fieldName, Ptr fieldAddr, 
 short fieldType, void *link), void *link);

class TSizer : public TCommand {
 TTEDocument   *fTEDocument;
 TBox   *fBox;   RectoldLocation;  RectnewLocation;      Point 
 fStart;  // mouse pressed here
 Point  fDelta;  // offset moved
 // flags to indicate which coordinates to change
 pascal void ISizer(TBox *itsBox, 
 TTEDocument *itsDocument, TTextView *itsView);
 pascal struct TCommand *TrackMouse
 (TrackPhase aTrackPhase, VPoint *anchorPoint, 
 VPoint *previousPoint, VPoint *nextPoint, 
 Boolean mouseDidMove);
 pascal void TrackFeedback
 (VPoint *anchorPoint, VPoint *nextPoint,
 Boolean turnItOn, Boolean mouseDidMove);
 pascal void DoIt();
 pascal void RedoIt();
 pascal void UndoIt();
#ifdef qDebug
 virtual pascal void Fields(pascal void (*DoToField) 
 (StringPtr fieldName, Ptr fieldAddr, 
 short fieldType, void *link), void *link);
Listing 2: Change to TTextView::DoMouseCommand (file TEDrag.cp)
 if (aFindBoxStruct.myBox->fSelected)
 { if (info->theShiftKey) 
 { aFindBoxStruct.myBox->fSelected = false;
 InvalidRect (&aFindBoxStruct.myBox->fLocation);
 return inherited::DoMouseCommand
 { if (PtInRgn(*theMouse,
 { aSizer = new TSizer;
 aSizer->ISizer (aFindBoxStruct.myBox,
  fTEDocument, this);
 return aSizer;   }
 { aDragger = new TDragger;
 (aFindBoxStruct.myBox, fTEDocument, this);
 return aDragger;   }
 if (!info->theShiftKey) 
 { fTEDocument->ForEachShapeDo
 ((DoToObject)Deselect, &aSelectStruct); }
 aFindBoxStruct.myBox->fSelected = true;
 InvalidRect(&aFindBoxStruct.myBox-> fLocation);
 return inherited::DoMouseCommand
Listing 3: TBox.cp
#include <UMacApp.h>
#include <UTEView.h>
#include <ToolUtils.h>
#include “TEDrag.h”

const int kBoxColor= redColor;
const int cSizer = 4001;
// Resizing support, JL 2/91
pascal void TSizer::ISizer(TBox *itsBox, 
 TTEDocument *itsDocument, TTextView *itsView)
 TScroller *aScroller;

 aScroller = itsView->GetScroller(true);
 ICommand(cSizer, itsDocument, itsView, aScroller);
 fTEDocument = itsDocument;
 fTextView = itsView;
 fBox = itsBox;  
 pT = false; pB = false; pL = false; pR = false;
 oldLocation = fBox->fLocation;
 newLocation = oldLocation;

pascal struct TCommand *TSizer::TrackMouse
 (TrackPhase aTrackPhase, VPoint *anchorPoint, 
 VPoint *previousPoint,  VPoint *nextPoint, 
 Boolean mouseDidMove)
 fStart = fTextView->ViewToQDPt(anchorPoint);
 if (aTrackPhase == trackPress) {
 if (PtInRect(fStart,&fBox->fTR)) { pT = true; pR = true; }
 else if (PtInRect(fStart,&fBox->fTL))
 { pT = true; pL = true; }
 else if (PtInRect(fStart,&fBox->fBR))
 { pB = true; pR = true; }
 else if (PtInRect(fStart,&fBox->fBL))
 { pB = true; pL = true; }
 else if (PtInRect(fStart,&fBox->fT)) { pT = true; }
 else if (PtInRect(fStart,&fBox->fB)) { pB = true; }
 else if (PtInRect(fStart,&fBox->fL)) { pL = true; }
 else if (PtInRect(fStart,&fBox->fR)) { pR = true; }

 if ((aTrackPhase == trackMove) && mouseDidMove) {
 fDelta = fTextView->ViewToQDPt(nextPoint);
 SubPt(fTextView->ViewToQDPt(anchorPoint), &fDelta);
 if ( !((fDelta.h == 0) && (fDelta.v == 0)) ) {                
 if (pT){ = + fDelta.v;  }
 if (pB){ newLocation.bottom = 
 oldLocation.bottom + fDelta.v; }
 if (pL){ newLocation.left = 
 oldLocation.left + fDelta.h; }
 if (pR){ newLocation.right = 
 oldLocation.right + fDelta.h; }

 if ((aTrackPhase == trackRelease) && mouseDidMove) {
 fDelta = fTextView->ViewToQDPt(nextPoint);
 SubPt(fTextView->ViewToQDPt(anchorPoint), &fDelta);
 if ((fDelta.h == 0) && (fDelta.v == 0))
 { return gNoChanges; }
 fBox->fLocation = newLocation;
 return this;

pascal void TSizer::TrackFeedback
 (VPoint *anchorPoint, VPoint *nextPoint,
 Boolean turnItOn, Boolean mouseDidMove)
 PenState oldState;
 if (mouseDidMove) {

pascal void TSizer::DoIt()
 fTextView->InvalidRect(&oldLocation);   }

pascal void TSizer::RedoIt()  
{  fBox->fLocation = newLocation; DoIt();    }

pascal void TSizer::UndoIt()
{fBox->fLocation = oldLocation; DoIt();      }

#ifdef qDebug
pascal void TSizer::Fields(pascal void (*DoToField) 
 (StringPtr fieldName, Ptr fieldAddr, 
 short fieldType, void *link), void *link)
 DoToField(“\pTSizer”, nil, bClass, link);
 (Ptr) &fTEDocument, bObject, link);
 DoToField(“\pfTextView”, (Ptr) &fTextView, bObject, link);
 DoToField(“\pfBox”, (Ptr) &fBox, bObject, link);
 DoToField(“\poldLocation”, (Ptr) &oldLocation, bRect, link);
 DoToField(“\pnewLocation”, (Ptr) &newLocation, bRect, link);
 DoToField(“\pfStart”, (Ptr) &fStart, bPoint, link);
 DoToField(“\pfDelta”, (Ptr) &fDelta, bPoint, link);
 DoToField(“\ppT”, (Ptr) &pT, bBoolean, link);
 DoToField(“\ppB”, (Ptr) &pB, bBoolean, link);
 DoToField(“\ppL”, (Ptr) &pL, bBoolean, link);
 DoToField(“\ppR”, (Ptr) &pR, bBoolean, link);
 inherited::Fields(DoToField, link);

pascal void TBox::IBox(Rect *itsLocation)
 {    fLocation = *itsLocation; fSelected = false; }

pascal void TBox::DrawShape()
 if (fSelected) {
 short halfH, halfV;
 halfH = (fLocation.right-fLocation.left)/2;
 halfV = (;
 PenSize (1,1);
 fTagRgn = MakeNewRgn();
 OpenRgn(); =;
 fTL.left = fLocation.left;
 fTL.bottom = + 4;
 fTL.right = fTL.left + 4;
 FrameRect(&fTL); =;
 fT.bottom = + 4;
 fT.left = fLocation.left + halfH - 2;
 fT.right = fT.left + 4;
 FrameRect(&fT); =;
 fTR.bottom = + 4;
 fTR.right = fLocation.right;
 fTR.left = fTR.right - 4;
 fBL.bottom = fLocation.bottom; = fBL.bottom - 4;
 fBL.left = fLocation.left;
 fBL.right = fBL.left + 4;
 fB.bottom = fLocation.bottom; = fB.bottom - 4;
 fB.left = fLocation.left + halfH - 2;
 fB.right = fB.left + 4;
 fBR.bottom = fLocation.bottom; = fBR.bottom - 4;
 fBR.right = fLocation.right;
 fBR.left = fBR.right - 4;
 FrameRect(&fBR); = + halfV - 2;
 fL.bottom = + 4;
 fL.left = fLocation.left;
 fL.right = fL.left + 4;
 FrameRect(&fL); = + halfV - 2;
 fR.bottom = + 4;
 fR.right = fLocation.right;
 fR.left = fR.right - 4;
 ForeColor(kBoxColor);  }
   the rest of the file (TShape and following definitions) stays unchanged 
Listing 4: Change to TEDrag.r

#define cSizer   4001
resource ‘cmnu’ (128) {
 128, textMenuProc, allEnabled, enabled, “Buzzwords”,          /* these 
words appear after Undo in the Edit menu */
 “Page Setup Change”, noIcon, noKey, 
 noMark, plain, cChangePrinterStyle;
 “Typing”, noIcon, noKey, noMark, plain, cTyping;
 “Drawing”,  noIcon, noKey, 
 noMark, plain, cDrawBox;
 “Dragging”,  noIcon, noKey, 
 noMark, plain, cDragBox;
 “Resize”,  noIcon, noKey, noMark, plain, cSizer
Listing 5: TEDrag.MAMake
AppName = TEDrag
OtherInterfaces =  
OtherLinkFiles = 
“{ObjApp}TBox.cp.o”ƒ 
 “{SrcApp}TBox.cp” 
 “{SrcApp}TEDrag.MAMake” 
  {MacAppIntf} 
 {MAEcho} {EchoOptions} “Compiling:     TBox.cp”
 {MACPlus} 
 {CPlusOptions} 
 -s TBox 
 -i “{SrcApp}” 
 -i “{MACIncludes}” 
 -o “{ObjApp}TBox.cp.o” 
OtherRsrcFiles = 
 “{MAObj}Printing.rsrc” 


Community Search:
MacTech Search:

Software Updates via MacUpdate

Microsoft Office 2016 16.11 - Popular pr...
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
Adobe Photoshop CC 2018 19.1.2 - Profess...
Photoshop CC 2018 is available as part of Adobe Creative Cloud for as little as $19.99/month (or $9.99/month if you're a previous Photoshop customer). Adobe Photoshop CC 2018, the industry standard... Read more
Adobe Dreamweaver CC 2018 -...
Dreamweaver CC 2018 is available as part of Adobe Creative Cloud for as little as $19.99/month (or $9.99/month if you're a previous Dreamweaver customer). Adobe Dreamweaver CC 2018 allows you to... Read more
Adobe Flash Player - Plug-in...
Adobe Flash Player is a cross-platform, browser-based application runtime that provides uncompromised viewing of expressive applications, content, and videos across browsers and operating systems.... Read more
Drive Genius 5.2.0 - $79.00
Drive Genius features a comprehensive Malware Scan. Automate your malware protection. Protect your investment from any threat. The Malware Scan is part of the automated DrivePulse utility. DrivePulse... Read more
MegaSeg 6.0.6 - Professional DJ and radi...
MegaSeg is a complete solution for pro audio/video DJ mixing, radio automation, and music scheduling with rock-solid performance and an easy-to-use design. Mix with visual waveforms and Magic... Read more
ffWorks 1.0.7 - Convert multimedia files...
ffWorks (was iFFmpeg), focused on simplicity, brings a fresh approach to the use of FFmpeg, allowing you to create ultra-high-quality movies without the need to write a single line of code on the... Read more
Dash 4.1.5 - 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
Evernote 7.0.3 - Create searchable notes...
Evernote allows you to easily capture information in any environment using whatever device or platform you find most convenient, and makes this information accessible and searchable at anytime, from... Read more
jAlbum Pro 15.3 - Organize your digital...
jAlbum Pro has all the features you love in jAlbum, but comes with a commercial license. You can create gorgeous custom photo galleries for the Web without writing a line of code! Beginner-friendly... Read more

Latest Forum Discussions

See All

Around the Empire: What have you missed...
Oh hi nice reader, and thanks for popping in to check out our weekly round-up of all the stuff that you might have missed across the Steel Media network. Yeah, that's right, it's a big ol' network. Obviously 148Apps is the best, but there are some... | Read more »
All the best games on sale for iPhone an...
It might not have been the greatest week for new releases on the App Store, but don't let that get you down, because there are some truly incredible games on sale for iPhone and iPad right now. Seriously, you could buy anything on this list and I... | Read more »
Everything You Need to Know About The Fo...
In just over a week, Epic Games has made a flurry of announcements. First, they revealed that Fortnite—their ultra-popular PUBG competitor—is coming to mobile. This was followed by brief sign-up period for interested beta testers before sending out... | Read more »
The best games that came out for iPhone...
It's not been the best week for games on the App Store. There are a few decent ones here and there, but nothing that's really going to make you throw down what you're doing and run to the nearest WiFi hotspot in order to download it. That's not to... | Read more »
Death Coming (Games)
Death Coming Device: iOS Universal Category: Games Price: $1.99, Version: (iTunes) Description: --- Background Story ---You Died. Pure and simple, but death was not the end. You have become an agent of Death: a... | Read more »
Hints, tips, and tricks for Empires and...
Empires and Puzzles is a slick match-stuff RPG that mixes in a bunch of city-building aspects to keep things fresh. And it's currently the Game of the Day over on the App Store. So, if you're picking it up for the first time today, we thought it'd... | Read more »
What You Need to Know About Sam Barlow’s...
Sam Barlow’s follow up to Her Story is #WarGames, an interactive video series that reimagines the 1983 film WarGames in a more present day context. It’s not exactly a game, but it’s definitely still interesting. Here are the top things you should... | Read more »
Pixel Plex Guide - How to Build Better T...
Pixel Plex is the latest city builder that has come to the App Store, and it takes a pretty different tact than the ones that came before it. Instead of being in charge of your own city by yourself, you have to work together with other players to... | Read more »
Fortnite Will Be Better Than PUBG on Mob...
Before last week, if you asked me which game I prefer between Fortnite Battle Royale and PlayerUnknown’s Battlegrounds (PUBG), I’d choose the latter just about 100% of the time. Now that we know that both games are primed to hit our mobile screens... | Read more »
Siege of Dragonspear (Games)
Siege of Dragonspear 2.5.12 Device: iOS Universal Category: Games Price: $9.99, Version: 2.5.12 (iTunes) Description: Experience the Siege of Dragonspear, an epic Baldur’s Gate tale, filled with with intrigue, magic, and monsters.... | Read more »

Price Scanner via

Sunday Sales: $200 off 13″ Touch Bar MacBook...
Amazon has new 2017 13″ 3.1GHz Touch Bar MacBook Pros on sale this weekend for $200 off MSRP, each including free shipping: – 13″ 3.1GHz/256GB Space Gray MacBook Pro (MPXV2LL/A): $1599.99 $200 off... Read more
B&H drops prices on 15″ MacBook Pros up t...
B&H Photo has dropped prices on new 2017 15″ MacBook Pros, now up to $300 off MSRP and matching Adorama’s price drop yesterday. Shipping is free, and B&H charges sales tax for NY & NJ... Read more
Apple restocks Certified Refurbished 2017 13″...
Apple has restocked Certified Refurbished 2017 13″ 2.3GHz MacBook Pros for $200-$230 off MSRP. A standard Apple one-year warranty is included with each MacBook, models receive new outer cases, and... Read more
13″ Space Gray Touch Bar MacBook Pros on sale...
Adorama has new 2017 13″ Space Gray Touch Bar MacBook Pros on sale for $150 off MSRP. Shipping is free, and Adorama charges sales tax in NY & NJ only: – 13″ 3.1GHz/256GB Space Gray MacBook Pro (... Read more
Best deal of the year on 15″ Apple MacBook Pr...
Adorama has New 2017 15″ MacBook Pros on sale for up to $300 off MSRP. Shipping is free, and Adorama charges sales tax in NJ and NY only: – 15″ 2.8GHz Touch Bar MacBook Pro Space Gray (MPTR2LL/A): $... Read more
Save $100-$150+ on 13″ Touch Bar MacBook Pros...
B&H Photo has 13″ Touch Bar MacBook Pros on sale for $100-$150 off MSRP. Shipping is free, and B&H charges sales tax for NY & NJ residents only: – 13″ 3.1GHz/256GB Space Gray MacBook Pro... Read more
Current deals on 27″ Apple iMacs, models up t...
B&H Photo has 27″ iMacs on sale for up to $150 off MSRP. Shipping is free, and B&H charges sales tax for NY & NJ residents only: – 27″ 3.8GHz iMac (MNED2LL/A): $2149 $150 off MSRP – 27″ 3... Read more
Thursday Deal: 13″ 2.3GHz MacBook Pro for $11...
B&H Photo has the 13″ 2.3GHz/128GB Space Gray MacBook Pro on sale for $100 off MSRP. Shipping is free, and B&H charges sales tax for NY & NJ residents only: – 13-inch 2.3GHz/128GB Space... Read more
How to save $100-$190 on 10″ & 12″ iPad P...
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
Silver 12″ 1.3GHz MacBook on sale at B&H...
B&H Photo has the 2017 12″ 1.3GHz Silver MacBook on sale for $1399.99 including free shipping plus sales tax for NY & NJ residents only. Their price is $200 off MSRP, and it’s the lowest... Read more

Jobs Board

Firmware Engineer - *Apple* Accessories - A...
# Firmware Engineer - Apple Accessories Job Number: 113452350 Santa Clara Valley, California, United States Posted: 28-Feb-2018 Weekly Hours: 40.00 **Job Summary** Read more
Automation and Performance Engineer, *Apple*...
# Automation and Performance Engineer, Apple Pay Job Number: 113557967 Santa Clara Valley, California, United States Posted: 09-Mar-2018 Weekly Hours: 40.00 **Job Read more
Hardware Systems Architect - *Apple* Watch...
# Hardware Systems Architect - Apple Watch Job Number: 113565323 Santa Clara Valley, California, United States Posted: 05-Mar-2018 Weekly Hours: 40.00 **Job Read more
Lead *Apple* Solution Consultant - Apple (U...
# Lead Apple Solution Consultant Chicago IL Job Number: 113560644 Chicago, Illinois, United States Posted: 10-Mar-2018 Weekly Hours: 40.00 **Job Summary** As a Lead Read more
Art Director, *Apple* Music + Beats1 Market...
# Art Director, Apple Music + Beats1 Marketing Design Job Number: 113258081 Culver City, California, United States Posted: 07-Mar-2018 Weekly Hours: 40.00 **Job Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.