TweetFollow Us on Twitter

Winter 91 - SYS 7 Q&A

SYSTEM 7.0 Q & A

MACINTOSH DEVELOPER TECHNICAL SUPPORT

Q When I use the name and vRefNum returned from FindFolder, I always get a fnfErr from OpenRFPerm. Why?

A FindFolder returns both a vRefNum and a DirID. They both must be used to identify the folder. Instead of using OpenRFPerm,which takes only a vRefNum, try HOpenResFile. Avoid using PBHSetVol! (See Technical Note #140 for more information.)

Q We want to use OpenCPicture for higher resolution, not for color per se. Can OpenCPicture in System 7.0 be used with non-Color as well as Color QuickDraw Macintosh computers?

A Yes, with System 7.0, OpenCPicture can be used to create extended PICT2 files from all Macintosh computers. Under System 6.0.7 or later, you must test for 32-Bit QuickDraw before using OpenCPicture. You can do this by calling Gestalt with the gestaltQuickDrawVersion selector. If it returns gestalt32BitQD or greater, then 32-Bit QuickDraw is installed.Q Can the Communications Toolbox be used in a DA? InitCM has to be called and the manual says it should be called only once.

A Yes, it is all right to call CTB Initialization routines from CODE resources. This includes a DRVR, cdev, or INIT.

Q Can I use my 8*24 GC card with System 7.0ßx? I was told the GC misbehaves with any and all nonlinear address mapping, such as System 7.0 and A/UX. Is this true? Can this be fixed with CODE/INIT patch? Is it scheduled to be fixed in the near future?

A The 8*24 GC card software version 1.0 is not intended to run in any environment involving virtual memory management. A VM-compatible version of the GC software will be made available when System 7.0 is final. Until then, the card can be used as a video buffer, and System 7.0 preliminary software might run with VM switched off.Q Under what System 7.0 and System 6.0 conditions is it legal to call the QDError function?

A Under System 7.0, QDError can be called from all Macintosh computers. (System 7.0 supports RGBForeColor, RGBBackColor, GetForeColor, and GetBackColor for all Macintosh computers as well.) On a non-Color QuickDraw Macintosh, QDError always returns a "no error." Under System 6.0, QDError cannot be used for non-Color QuickDraw Macintosh systems.

Q Why do some CopyBits transfer modes produce different results for System 7.0 than for System 6.0?

A Under System 6.0, the srcOr, srcXor, srcBic, notSrcCopy, notSrcOr, notSrcXor, and notSrcBic transfer modes do not produce the same effect for a 16- or 32-bit (direct) pixel map as for an 8-bit or shallower (indexed) pixel map. With Color QuickDraw these classic transfer modes on direct pixel maps aren't color based; they're pixel value based. Color QuickDraw performs logical operations corresponding to the transfer mode on the source and destination pixel values to get the resulting pixel value.For example, say that a multicolored source is being copied onto a black and white destination using the srcOr transfer mode, and both the source and destination are 8 bits per pixel. Except in unusual cases, the pixel value for black on an indexed pixel map has all its bits set, so an 8-bit black pixel has a pixel value of $FF. Similarly, the pixel value for white has all its bits clear, so an 8-bit white pixel has a pixel value of $00. CopyBits takes each pixel value of the source and performs a logical OR with the corresponding pixel value of the destination. Using OR to combine any value with 0 results in the original value, so any pixel value ORed with the pixel value for white results in the original pixel value. Using OR to combine any value with 1 results in 1, so any pixel value ORed with the pixel value for black results in the pixel value for black. The resulting image shows the original image in all areas where the destination image was white and shows black in all areas where the destination image was black.

Take the same example, but this time make the source and destination 32 bits per pixel. The direct- color pixel value for black is $00000000 and the direct-color pixel value for white is $00FFFFFF. CopyBits still performs a logical OR on the source and destination pixel values, but notice what happens in this case. Using OR to combine any source pixel value with the pixel value for white results in white, and using OR to combine any source pixel value with the pixel value for black results in the original color. The resulting image shows the original image in all areas where the destination image was black and shows white in all areas where the destination image was white--roughly the opposite of what you see on an indexed pixel map.

The newer transfer modes addOver, addPin, subOver, subPin, adMax, and adMin work consistently at all pixel depths, and often, though not always, correspond to the theoretical effect of the old transfer modes. For example, the adMin mode works similarly to the srcOr mode on both direct and indexed pixel maps. Also, 1-bit deep source pixel maps work consistently and predictably regardless of the pixel depth of the destination even with the old transfer modes.

Under System Software 7.0, the old transfer modes now perform by calculating with colors rather than pixel values. You'll find that transfer modes like srcOr and srcBic work much more consistently even on direct pixel maps.

Q Is the Macintosh printing architecture different for System 7.0?

A No changes were made to the printing architecture for System 7.0. Printer drivers were revised for System 7.0 to support TrueType, to be completely 32-bit clean, and to fix bugs, but the printing architecture remains the same for System 7.0.Q BitMapToRegion does not work as described in Technical Note #275 for a PixMap with baseAddr = (NuBus address). Which calls support PixMap 32-bit base addressing with pmVersion = 4?

A As of System 7.0ß1, BitMapToRgn cannot handle a bitmap whose base address is in the NuBus TM address space or any bitmap that requires 32-bit addressing. The problem will be fixed for System 7.0's final release. As far as we know, BitMapToRgn is the only call that doesn't yet support 32-bit addressed bitmaps.

Q Can the LaserWriter 7.x driver be used with System 6.0?

A Yes! LaserWriter 7.x is compatible with both System 7.0 and System 6.0. It's still prerelease software, however. Do not ship the preliminary LaserWriter 7.x driver with your application. You'll be able to ship the final LaserWriter 7 driver with your product as soon as System 7.0 is final. To use the new LaserWriter driver with an AppleShare print spooler, you need a special LaserPrep, available on developer CDs and on AppleLink.

Kudos to our readers who care enough to ask us terrific and well-thought-out questions. The answers to these puzzles have been supplied courtesy of our teams of technical gurus; our thanks to all. Special thanks to Pete "Luke Skywalker" Alexander, Jim "Im" Beninghaus, Rich Collyer, Guillermo Ortiz, Forrest Tanaka, and Scott "Zz" Zimmerman for the material in this Q & A column. *

Have more questions? Need more answers? Take a look at the new developer technical library on AppleLink (updated weekly) or the Q & A stack on the disc that comes withdevelop . *

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

WhatsApp 0.2.5862 - Desktop client for W...
WhatsApp is the desktop client for WhatsApp Messenger, a cross-platform mobile messaging app which allows you to exchange messages without having to pay for SMS. WhatsApp Messenger is available for... Read more
Things 3.1.3 - Elegant personal task man...
Things is a task management solution that helps to organize your tasks in an elegant and intuitive way. Things combines powerful features with simplicity through the use of tags and its intelligent... Read more
BetterTouchTool 2.292 - 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
Things 3.1.3 - Elegant personal task man...
Things is a task management solution that helps to organize your tasks in an elegant and intuitive way. Things combines powerful features with simplicity through the use of tags and its intelligent... Read more
BetterTouchTool 2.292 - 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
Bookends 12.8.3 - Reference management a...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Bookends uses the cloud to sync reference libraries on all the Macs you use.... Read more
Mellel 3.5.5 - The word processor for sc...
Mellel is the leading word processor for OS X and has been widely considered the industry standard since its inception. Mellel focuses on writers and scholars for technical writing and multilingual... Read more
Mellel 3.5.5 - The word processor for sc...
Mellel is the leading word processor for OS X and has been widely considered the industry standard since its inception. Mellel focuses on writers and scholars for technical writing and multilingual... Read more
Bookends 12.8.3 - Reference management a...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Bookends uses the cloud to sync reference libraries on all the Macs you use.... Read more
Carbon Copy Cloner 4.1.18 - Easy-to-use...
Carbon Copy Cloner backups are better than ordinary backups. Suppose the unthinkable happens while you're under deadline to finish a project: your Mac is unresponsive and all you hear is an ominous,... Read more

Guild sieges and soul gems in latest upd...
Webzen’s MU Origin hit app stores last year, giving fans of fantasy hack-n-slash MMOs like Diablo a new fix to fixate on. This latest update introduces a competitive guild battle, a fresh dungeon challenge, a mini-game and some elemental gems to... | Read more »
Little Red Lie (Games)
Little Red Lie 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: ARE YOU MORE AFRAID OF POVERTY THAN DEATH? Little Red Lie is a narrative-focused, interactive fiction experience that reduces... | Read more »
You can now apply to be Clash of Clans...
Earlier this month, word got out that the Builder, the trusty handiman who tirelessly built every single building inevery singleClash of Clansbase had called it quits. Sick of seeing his work destroyed endless, the Builder has set out for our world... | Read more »
Meshi Quest beginner's guide - how...
Meshi Quest is Square Enix's newest free-to-play release, and it's a real charmer. You start off as the head of a sushi restaurant, upgrading your food and equipment as you serve visitors heaping helpings of your delicious meals. As you progress,... | Read more »
BUST-A-MOVE JOURNEY (Games)
BUST-A-MOVE JOURNEY 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: BUST-A-MOVE Features:- Shoot bubbles and match 3 or more bubbles of the same color to make them pop!- Complete your... | Read more »
The best card combos in Clash Royale
Clash Royale is all about building a deck of units that synergise well. To help you get off to a flying start, we've put together a list of unit combinations that are incredibly effective. Looking for some choice 2v2 combos? Check out our guide. [... | Read more »
The best 2v2 card combos in Clash Royale
2v2 is making it's grand return toClash Royalequite soon. 2v2 has quickly become one of the game's most popular gameplay modes, though they still have yet to make it a permanent fixture in the game. 2v2 is exciting and adds some new flavor to... | Read more »
The best games we played this week - Aug...
Another busy week has come to a close. We played a lot of excellent games this week and now it's time to look back and reflect on some our favorites. Here are our picks for the week of August 18. [Read more] | Read more »
War Wings beginner's guide - how to...
War Wings is the newest project from well-established game maker Miniclip. It's a World War II aerial dogfighting game with loads of different airplane models to unlock and battle. The game offers plenty of single player and multiplayer action. We... | Read more »
How to win every 2v2 battle in Clash Roy...
2v2 is coming back to Clash Royale in a big way. Although it's only been available for temporary periods of time, 2v2 has seen a hugely positive fan response, with players clamoring for more team-based gameplay. Soon we'll get yet another taste of... | Read more »

Price Scanner via MacPrices.net

2016 MacBook Pros, Apple refurbished, availab...
Apple has Certified Refurbished 2016 15″ and 13″ MacBook Pros available starting at $1189. An Apple one-year warranty is included with each model, and shipping is free: – 15″ 2.7GHz Touch Bar Space... Read more
Apple offers Certified Refurbished iPhone 6s...
Apple has Certified Refurbished unlocked iPhone 6s’s and 6s Plus’s available starting at $449. An Apple one-year warranty is included with each phone, and shipping is free: – 16GB iPhone 6s: $449, $... Read more
Apple offers Certified Refurbished Pencils fo...
Apple has Certified Refurbished Apple Pencils available for $85 including free shipping. Their price is $14 off MSRP, and it’s the lowest price available for a Pencil. Read more
2016 15-inch 2.6GHz Touch Bar MacBook Pro ava...
B&H Photo has clearance 2016 15″ 2.6GHz MacBook Pros in stock today and on sale for $500 off original MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: – 15″ 2.6GHz Touch... Read more
21-inch 2.3GHz iMac on sale for $999, save $1...
Amazon has the new 2017 21″ 2.3GHz iMac (MMQA2LL/A) in stock and on sale for $999.99 including free shipping. Their price is $100 off MSRP, and it’s the lowest price available for this model. Read more
Free Instant Translator 2.0 App For iOS Relea...
Mobile application development company, Neoappz has announced the release and immediate availability of Instant Translator 2.0 for iOS devices. Instant Translator is a user-friendly application which... Read more
2017 15-inch MacBook Pros on sale for $200 of...
Amazon has 2017 15″ MacBook Pros on sale for $200 off MSRP. Shipping is free: – 15″ 2.8GHz MacBook Pro Space Gray: $2199.99, $200 off MSRP – 15″ 2.8GHz MacBook Pro Silver: $2296, $103 off MSRP – 15″... Read more
Apple’s 2017 Back to School Promotion: Free B...
Purchase a new Mac using Apple’s Education discount, and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free. As part... Read more
Clearance 2016 12-inch Retina MacBooks, Apple...
Apple has Certified Refurbished 2016 12″ Retina MacBooks available starting at $1019. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The following... Read more
15-inch 2.2GHz Retina MacBook Pro, Apple refu...
Apple has Certified Refurbished 2015 15″ 2.2GHz Retina MacBook Pros available for $1699. That’s $300 off MSRP, and it’s the lowest price available for a 15″ MacBook Pro. An Apple one-year warranty is... Read more

Jobs Board

Development Operations and Site Reliability E...
Development Operations and Site Reliability Engineer, Apple Payment Gateway Job Number: 57572631 Santa Clara Valley, California, United States Posted: Jul. 27, 2017 Read more
Frameworks Engineering Manager, *Apple* Wat...
Frameworks Engineering Manager, Apple Watch Job Number: 41632321 Santa Clara Valley, California, United States Posted: Jun. 15, 2017 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
Development Operations and Site Reliability E...
Development Operations and Site Reliability Engineer, Apple Payment Gateway Job Number: 57572631 Santa Clara Valley, California, United States Posted: Jul. 27, 2017 Read more
Frameworks Engineering Manager, *Apple* Wat...
Frameworks Engineering Manager, Apple Watch Job Number: 41632321 Santa Clara Valley, California, United States Posted: Jun. 15, 2017 Weekly Hours: 40.00 Job Summary Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.