TweetFollow Us on Twitter

Feb 94 Tips
Volume Number:10
Issue Number:2
Column Tag:Tips & Tidbits

Tips & Tidbits

By Neil Ticktin, Editor-in-Chief

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

Tip Of The Month

Playing a sound can be potentially disastrous. Suppose you have an init that plays a sound when a mail arrives on the network, but at the same time, e.g., HyperCard is playing, an (asynchronous) sound of its own. Both sounds will be stopped by a freeze or a crash.

I looked at the code of the _SysBeep trap, and came up with the ‘SafeSound’-procedure. It will only play the sound when it’s safe to do so. If the routine did not play the sound, it returns false so that you try again after, say, a few seconds.


/* 1 */
#define ExpandMem   0x02B6
#define WWExists   0x08F2

Boolean SafeSound (Handle snd)
{
  asm {
       move SR, D0   ; this little piece of code checks if
       andi.w    #0x0700, D0; we can play our sound !
       bne  @exit    ; Took it from code of the SysBeep-trap!
       movea.l   ExpandMem, A0
       movea.l   0x0110(A0), A0
       tst.w     0x0018(A0)
       beq  @exit
       tst.b     WWExists
       bne  @exit
    }

  SndPlay (NULL, snd, false) ;
  return true ;  // ok, sound is played

exit:
  return false;  // sound has not been played
}

- Jan Bruyndonckx

Wave Research

Belgium

This column is your opportunity to spread the word about little bits of information that you find out about. These tidbits can be programming related or they can be user tips that are particularly useful to programmers.

MacTech Magazine will pay $25 for every tip used, and $50 for the Tip of the Month. Or you can take your award in orders or subscriptions.

To submit a tip, send in a letter to the magazine. E-mail is our preferred method, but feel free to send something via the US Mail. See page two for all addresses. If you do send snail mail, enclose a printed copy and a disk copy of the letter so that it does not have to be retyped.

Changing Popup Fonts

There’s an easy way to change a Popup menu’s font and size. To do that, you could of course use the new CDEF provided with the Comm Toolbox, but it will not work for Pre-System 7 users.

An alternative solution is to change system font and size before PopUpMenuSelect is called, and restore them afterwards. Typical code looks like:

/* 2 */

TYPE
 LomemPtrWord=^Integer;
 LomemPtrLong=^Longint;

VAR
 SysFont, SysSize:Integer;
 PopUpResult:Longint;

{-1 means hierarchical menu}
InsertMenu(MyPopUpID, -1);  

{ Let's save system font and size }
SysFont := LomemPtrWord($0BA6) ^;  {SysFontFam}
SysSize := LomemPtrWord($0BA8) ^;  {SysFontSize}

{Modfy to our convenience (Geneva 10)}
LomemPtrWord($0BA6) ^ := Geneva;
LomemPtrWord($0BA8) ^ := 10;
LomemPtrLong($0B4C) ^ := -1;

{ This line insure that system will }
{ load the right font in the cache }
{ for the next job--drawing my Popup }
ResultPopUp := PopUpMenuSelect(MyPopUpHandle, Where.v, 
 Where.h, DefaultItem);

{ Let's restore system configuration }
LomemPtrWord($0BA6) ^ := SysFont;
LomemPtrWord($0BA8) ^ := SysSize;
LomemPtrLong($0B4C) ^ := -1;

{ Insure that usual system font will be back loaded }
DeleteMenu(MyPopUpID);
{...}
{PopUp Process }
{...} 

Remark 1 : If you’re using CheckItem call, be sure that CheckMark character exists in the font and size you want popup menu to be drawn. If not, use SetItemMark instead.

Remark 2 : Modifying directly low memory globals is discouraged by Apple. Future system releases could break this tip. Keep this in mind.

- Laurent Haas

Paris, France

Often Used Field Positions

For data structures accessed via pointers or handles, place the most often used field in your program in the first place of your data structure declaration.

The Optimal Data Structure Declaration is:

/* 3 */

TYPE
 YourDataStructurePtr = ^YourDataStructure;
 YourDataStructure = RECORD
 often_Used_Field:LongInt;
 less_Often_Used_Field:LongInt;
 END;
Less Optimal Data Structure Declaration:

TYPE
 YourDataStructurePtr = ^YourDataStructure;
 YourDataStructure = RECORD
 less_Often_Used_Field:LongInt;
 often_Used_Field:LongInt;
 END;

The compiler will generate 66% faster code for the optimal data structure when it compiles the next line:

/* 4 */
yourDataStructurePtr^.often_Used_Field:=someValue;

- Marek Hajek

Incline Village, Nevada

It’s in the fine print

The integration of translators in Think C 6.0 has a few rough areas that are not so obvious, unless you read the fine print in the manual. Unless you never make assumptions about how a feature works, read on....

First, if you use both the C and C++ translators in the same project, you could have problems. The C translator allows you to choose whether you want two or four byte integers. The C++ translator doesn’t give you a choice. Integers are always four bytes. So if you want your C code to co-exist peacefully with your C++ code, you must tell the C translator to use four byte integers. Here is the menu/dialog selections you must make to select four byte integers - “Edit:Options:Think C...:Compiler Settings:4-byte ints”

Second, the project settings allow you to put strings in the data segment of the project, or in separate STRS resources. In the “Set Project Type...” option under the “Project” menu, there is a check box “Separate STRS” that you can use to toggle this setting. It isn’t obvious, but this toggle only affects the C translator. To toggle the same setting for the C++ translator you must make the following menu/dialog selections: “Edit:Options:Symantec C++:Compiler Settings:Place string literals in code”.

- Greg Johnson

WordPerfect Corp.

Orem, Utah

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

RapidWeaver 6.0.8 - Create template-base...
RapidWeaver is a next-generation Web design application to help you easily create professional-looking Web sites in minutes. No knowledge of complex code is required, RapidWeaver will take care of... Read more
Artlantis Studio 5.1.2.7 - 3D rendering...
Artlantis Studio is a unique and ideal tool for performing very high resolution rendering easily and in real time. The new FastRadiosity engine now lets you compute images in radiosity-even in... Read more
MacUpdate Desktop 6.0.5 - Search and ins...
MacUpdate Desktop 6 brings seamless 1-click installs and version updates to your Mac. With a free MacUpdate account and MacUpdate Desktop 6, Mac users can now install almost any Mac app on macupdate.... Read more
BitTorrent Sync 2.0.82 - Sync files secu...
BitTorrent Sync allows you to sync unlimited files between your own devices, or share a folder with friends and family to automatically sync anything. File transfers are encrypted. Your information... Read more
Google Drive 1.20 - File backup and shar...
Google Drive is a place where you can create, share, collaborate, and keep all of your stuff. Whether you're working with a friend on a joint research project, planning a wedding with your fiancé, or... Read more
Simon 4.0.3 - Monitor changes and crashe...
Simon monitors websites and alerts you of crashes and changes. Select pages to monitor, choose your alert options, and customize your settings. Simon does the rest. Keep a watchful eye on your... Read more
Vitamin-R 2.23 - Personal productivity t...
Vitamin-R creates the optimal conditions for your brain to work at its best by structuring your work into short bursts of distraction-free, highly focused activity alternating with opportunities for... Read more
iDefrag 5.0.0 - Disk defragmentation and...
iDefrag helps defragment and optimize your disk for improved performance. Features include: Supports HFS and HFS+ (Mac OS Extended). Supports case sensitive and journaled filesystems. Supports... Read more
PCalc 4.2 - Full-featured scientific cal...
PCalc is a full-featured, scriptable scientific calculator with support for hexadecimal, octal, and binary calculations, as well as an RPN mode, programmable functions, and an extensive set of unit... Read more
FileZilla 3.10.2 - Fast and reliable FTP...
FileZilla (ported from Windows) is a fast and reliable FTP client and server with lots of useful features and an intuitive interface. Version 3.10.2: Note: Now requires a 64-bit Intel processor.... Read more

Warner Bros. Interactive Entertainment A...
Warner Bros. has some exciting games coming down the pipe! | Read more »
GDC 2015 – Star Trek Timelines will Prob...
GDC 2015 – Star Trek Timelines will Probably Make Your Inner Trekkie Squeal With Glee Posted by Rob Rich on March 4th, 2015 [ permalink ] Any popular fictional universe has its fair share of fan fiction – where belo | Read more »
Protect Yourself from an Onslaught of Ca...
Surprise Attack Games has announced a Cat-astrophic new physics puzzler called Fort Meow! In the game, a young girl named Nia finds her grandfather’s journal which triggers an all mighty feline attack! Why do the cats want the journal? Who knows,... | Read more »
GDC 2015 – Jelly Reef will be Game Oven’...
GDC 2015 – Jelly Reef will be Game Oven’s Last Hurrah, and it Seems like a Good Note to Go Out on Posted by Rob Rich on March 4th, 2015 [ permalink ] It’s sad knowing that Game Oven ( | Read more »
daWindci Deluxe Review
daWindci Deluxe Review By Campbell Bird on March 4th, 2015 Our Rating: :: BLUSTERY PUZZLESUniversal App - Designed for iPhone and iPad This updated puzzle game offers some creative gameplay and new mechanics, but still suffers from... | Read more »
Dungeon Hunter 5 Coming on March 12
Gameloft has excitedly announced that Dungeon Hunter 5 is on its way! Once again, you will adventure across the land of Valenthia exploring dungeons and fighting monsters. The game will have a new asynchronous multiplayer mode called Strongholds... | Read more »
GDC 2015 – The Sandbox 2 is Coming, and...
GDC 2015 – The Sandbox 2 is Coming, and Now it has Textures! | Read more »
Warner Bros. Interactive Announces Mort...
Mortal Kombat X, by Warner Bros. and NetherRealm Studios, will be a a free-to-play fighting/card-battle Mortal Kombat game. The game promises card collecting, multiplayer team combat, classic characters such as Scorpion, Sub-Zero and Raiden, and the... | Read more »
GDC 2015 – Piloteer is Whitaker Trebella...
GDC 2015 – Piloteer is Whitaker Trebella’s Latest Project, and it’s Definitely Something DIfferent Posted by Rob Rich on March 3rd, 2015 [ permalink ] You know | Read more »
PangoLand Review
PangoLand Review By Amy Solomon on March 3rd, 2015 Our Rating: :: COME VISIT PANGO AND FRIENDSUniversal App - Designed for iPhone and iPad PangoLand is an open-ended world full of familiar characters, bright colors and interactive... | Read more »

Price Scanner via MacPrices.net

iPad: A More Positive Outlook – The ‘Book Mys...
It’s good to hear someone saying positive things about the iPad. I’ve been trying to bend my mind around how Apple’s tablet could have gone from zero to bestselling personal computing device on the... Read more
Mac Pros on sale for up to $279 off MSRP
Amazon has Mac Pros in stock and on sale for up to $279 off MSRP. Shipping is free: - 4-Core Mac Pro: $2725.87, $273 off MSRP (9%) - 6-Core Mac Pro: $3719.99, $279 off MSRP (7%) Read more
Sale! 13-inch Retina MacBook Pros for up to $...
B&H Photo has 13″ Retina MacBook Pros on sale for up to $205 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 2.6GHz/128GB Retina MacBook Pro: $1219.99 save $80 - 13″ 2.... Read more
Another Tranche Of IBM MobileFirst For iOS Ap...
IBM has announced the next expansion phase for  its IBM MobileFirst for iOS portfolio, with a troika of new apps to address key priorities for the Banking and Financial Services, Airline and Retail... Read more
Sale! 15-inch Retina MacBook Pros for up to $...
B&H Photo has the new 2014 15″ Retina MacBook Pros on sale for up to $250 off MSRP for a limited time. Shipping is free, and B&H charges NY sales tax only: - 15″ 2.2GHz Retina MacBook Pro: $... Read more
WaterField Designs Introduces the Minimalist...
With Apple Pay gaining popularity, Android Pay coming in May 2015, and loyalty cards and receipts that can be accessed from smartphones, San Francisco’s WaterField Designs observes that it may be... Read more
Sale! 15-inch 2.2GHz Retina MacBook Pro for $...
 Best Buy has the 15″ 2.2GHz Retina MacBook Pro on sale for $1774.99 $1799.99, or $225 off MSRP. Choose free home shipping or free local store pickup (if available). Price valid for online orders... Read more
13-inch 2.5GHz MacBook Pro (refurbished) avai...
The Apple Store has Apple Certified Refurbished 13″ 2.5GHz MacBook Pros available for $170 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.5GHz... Read more
13-inch 2.5GHz MacBook Pro on sale for $100 o...
B&H Photo has the 13″ 2.5GHz MacBook Pro on sale for $999.99 including free shipping plus NY sales tax only. Their price is $100 off MSRP. Read more
27-inch 3.5GHz 5K iMac in stock today and on...
 B&H Photo has the 27″ 3.5GHz 5K iMac in stock today and on sale for $2299 including free shipping plus NY sales tax only. Their price is $200 off MSRP, and it’s the lowest price available for... Read more

Jobs Board

*Apple* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
Position Opening at *Apple* - Apple (United...
…Summary** As a Specialist, you help create the energy and excitement around Apple products, providing the right solutions and getting products into customers' hands. You Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** The Apple Store is a retail environment like no other - uniquely focused on delivering amazing customer experiences. As an Expert, you introduce people Read more
*Apple* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
*Apple* Pay Automation Engineer - iOS System...
**Job Summary** At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring passion and dedication to your job Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.