TweetFollow Us on Twitter

June 96 - Print Hints: The Top 10 Printing Crimes Revisited

Print Hints: The Top 10 Printing Crimes Revisited

DAVE POLASCHEK

They say some things never change. Although it's been four years since Pete "Luke" Alexander wrote about the top 10 printing crimes in develop, people are still committing some of the same crimes. There are also a few new crimes to add to the list. So, here they are, the updated top 10 printing crimes (ordered on a combined frequency and hideousness scale):


    10. Having insufficient free memory at print time.

    9. Coloring outside the lines.

    8. Misusing the PostScriptHandle picture comment.

    7. Calling PrintDefault or PrValidate before PrOpen.

    6. Avoiding the print dialogs, especially PrJobDialog.

    5. Accessing undocumented fields in the print record.

    4. Not checking error return values.

    3. Making low-level Printing Manager calls.

    2. Not using QuickDraw GX print dialogs if QuickDraw GX is present.

    1. Adding printing to your application last.

Now let's look at how to avoid these crimes. The solutions are relatively easy.

SOLVING THE PRINTING CRIMES

10. Having insufficient free memory at print time.

Some printer drivers use a lot of memory. When a driver runs out of memory, the results are usually pretty bad, so you should give printer drivers as much memory as possible. Unfortunately, memory requirements vary from driver to driver, so it's hard to predict how much memory a driver will need.

Solution: Unload all unneeded code and resources before printing.

9. Coloring outside the lines.

Many applications draw outside the printable area of the page when printing. This can happen if the user has extended objects beyond the printable area. Drawing unneeded objects causes extra work for the driver and the printer, which affects performance. In some cases, the driver also needs to allocate extra memory to hold the objects or the enclosing rectangle.

Solution: Draw only the portions of objects that will appear on the page. This can be determined by looking at the rPage field in the printer information record (which is in the prInfo field of the print record).

8. Misusing the PostScriptHandle picture comment.

The PostScriptHandle picture comment is designed to add PostScript (TM) code to a page containing QuickDraw graphics. It's not designed to send multiple pages of pre-generated PostScript code to a printer (for that, you need to use the Pap.WorkStation.o library).

Solution: Use the PostScriptHandle picture comment only to draw a self-contained image, which will be added to any QuickDraw graphics already on the page. If the PostScript code needs to change the graphics state, it should save and restore the state. Think of the picture comment as a way to include an EPS image, with all the restrictions placed on EPS by Adobe (TM) (as specified in Appendix H of the PostScript Language Reference Manual, second edition). The PostScript code should be compatible with both Level 1 and Level 2 PostScript, and you should include a QuickDraw version of the graphic so that your users can print to a non-PostScript printer.

    For more information on how to use the PostScriptHandle picture comment, see Technote 1032, "Mixing QuickDraw & PostScript Printing from Your App: Some Gotchas," and Appendix B of Inside Macintosh: Imaging With QuickDraw.*

7. Calling PrintDefault or PrValidate before PrOpen.

The documentation for the Printing Manager (Chapter 9 of Inside Macintosh: Imaging With QuickDraw) mentions that you need to call PrOpen before calling any other Printing Manager functions. Unfortunately, the descriptions for PrintDefault and PrValidate don't repeat this warning.

Solution: Always call PrOpen before calling any other Printing Manager calls.

6. Avoiding the print dialogs, especially PrJobDialog.

Some applications try to avoid print dialogs because either user interaction isn't possible or the developer thinks the user will make a mistake. Because all of the many options for the current drivers, most notably LaserWriter 8, cannot be stored in the print record, you need to call PrJobDialog so that the driver can read in the options from where they're stored (usually in the preferences file). If you don't call PrJobDialog, the driver can't set up the print record correctly, and you might not get the output you expected. The solution should be to call PrJobMerge, but in many drivers PrJobMerge does a less than perfect job.

Solution: Call PrJobDialog before printing to set up your print record correctly, or use QuickDraw GX, which supports dialog-free printing.

5. Accessing undocumented fields in the print record.

Many of the fields in the print record are undocumented or documented as private. Printer drivers can use these fields however they choose. What works for one driver might cause another to crash or to print zillions of pages you don't want.

Solution: Use only the fields in the print record that are documented as public in Chapter 9 of Inside Macintosh: Imaging With QuickDraw.

4. Not checking error return values.

After any call to a Printing Manager function, you should check PrError. If you're calling PrGeneral, you should also check the iError field in the TGnlData structure. Be aware that newer drivers return errors that older drivers didn't. For example, PrStlDialog in LaserWriter 8 can return an error if the preferences file is missing or corrupted; many applications don't check for this error, and later crash when they've pushed the driver completely off the cliff.

Solution: Always check and handle printing errors. See the Macintosh Technical Note "A Printing Loop That Cares..." (PR 10) and the article "Meet PrGeneral" in develop Issue 3.

3. Making low-level Printing Manager calls.

The low-level Printing Manager routines, such as PrDrvrOpen, are obsolete and unsupported.

Solution: Never call the low-level routines.

2. Not using QuickDraw GX print dialogs if QuickDraw GX is present.

When you call the classic Printing Manager functions and QuickDraw GX is active, the user gets the old-style "compatibility dialogs," which lack many of the features that are provided in the QuickDraw GX print dialogs. There are two problems with this: the user doesn't have access to all of the QuickDraw GX features; and when some applications call the QuickDraw GX print dialog functions and others don't, two very different printing experiences are presented to the user.

Solution: Call the QuickDraw GX print dialog functions in your print loop if QuickDraw GX is present. For help, see the article "Adding QuickDraw GX Printing to QuickDraw Applications" in develop Issue 19. The complete documentation can be found in Inside Macintosh: QuickDraw GX Printing.

1. Adding printing to your application last.

Four years later, this is still the number-one printing crime. A lot of developers leave printing until near the end of the product development cycle. When problems are encountered, Developer Technical Support gets messages like: "My application can't print, and I've got to ship today. Please answer as soon as possible."

Solution: Hook up your print loop as early as possible. As you add each new feature to your application, print a page or two. Make sure that things are still working as expected. When you take this approach, any features that cause printing problems get noticed early, and you'll have time to fix them.

A CLOSING NOTE

If you're committing any of the crimes on this list, your customers are probably seeing things they don't like when they print. This list is also far from comprehensive, as people continue to find new and unique ways to abuse the Macintosh print architecture.

Looking ahead, printing will be changing in a big way. Mac OS 8 will use QuickDraw GX as the printing model. As changes occur, there will be Technotes, develop articles, and other sources of information. So keep your eyes open, and remember, don't commit too many printing crimes. Crime doesn't pay.

DAVE POLASCHEK supports printing and font-related issues in Apple's Developer Technical Support group. Dave was last seen wandering the halls muttering, "This will all be better in Mac OS 8" and laughing maniacally.*

Thanks to Pete "Luke" Alexander, Paul Danbold, Dave Hersey, and Jim Zandee for reviewing this column.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Apple Remote Desktop 3.8 - Remotely cont...
Apple Remote Desktop is the best way to manage the Mac computers on your network. Distribute software, provide real-time online help to end users, create detailed software and hardware reports, and... Read more
NeoOffice 2014.7 - Mac-tailored, OpenOff...
NeoOffice is a complete office suite for OS X. With NeoOffice, users can view, edit, and save OpenOffice documents, PDF files, and most Microsoft Word, Excel, and PowerPoint documents. NeoOffice 3.x... Read more
DesktopLyrics 2.6.6 - Displays current i...
DesktopLyrics is an application that displays the lyrics of the song currently playing in "iTunes" right on your desktop. The lyrics for the song have to be set in iTunes; DesktopLyrics does nothing... Read more
Ember 1.8.3 - Versatile digital scrapboo...
Ember (formerly LittleSnapper) is your digital scrapbook of things that inspire you: websites, photos, apps or other things. Just drag in images that you want to keep, organize them into relevant... Read more
Apple iTunes 12.1 - Manage your music, m...
Apple iTunes lets you organize and play digital music and video on your computer. It can automatically download new music, app, and book purchases across all your devices and computers. And it's a... Read more
LibreOffice 4.4.3 - Free, open-source of...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
FoldersSynchronizer 4.2.1 - Synchronize...
FoldersSynchronizer is a popular and useful utility that synchronizes and backs-up files, folders, disks and boot disks. On each session you can apply special options like Timers, Multiple Folders,... Read more
Simon 4.0.2 - 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
Cocktail 8.1.2 - General maintenance and...
Cocktail is a general purpose utility for OS X that lets you clean, repair and optimize your Mac. It is a powerful digital toolset that helps hundreds of thousands of Mac users around the world get... Read more
Cyberduck 4.6.4 - FTP and SFTP browser....
Cyberduck is a robust FTP/FTP-TLS/SFTP browser for the Mac whose lack of visual clutter and cleverly intuitive features make it easy to use. Support for external editors and system technologies such... Read more

Playworld Superheroes Review
Playworld Superheroes Review By Tre Lawrence on January 30th, 2015 Our Rating: :: HERO CRAFTINGUniversal App - Designed for iPhone and iPad It’s all about the imagination, fighting bad creatures — and looking good while doing so.   | Read more »
Join the SpongeBob Bubble Party in this...
Join the SpongeBob Bubble Party in this New Match 3 Bubble Poppin’ Frenzy Posted by Jessica Fisher on January 30th, 2015 [ permalink ] | Read more »
Handpick Review
Handpick Review By Jennifer Allen on January 30th, 2015 Our Rating: :: TANTALIZING SUGGESTIONSiPhone App - Designed for the iPhone, compatible with the iPad Handpick will make you hungry, as well as inspire you to cook something... | Read more »
Storm the Halls of Echo Base in First St...
Storm the Halls of Echo Base in First Star Wars: Galactic Defense Event Posted by Jessica Fisher on January 30th, 2015 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Contradiction Review
Contradiction Review By Tre Lawrence on January 30th, 2015 Our Rating: :: SPOT THE LIEiPad Only App - Designed for the iPad Contradiction is a live action point and click adventure that’s pretty engaging.   Developer: Tim Follin... | Read more »
Unlock Sunshine Girl in Ironkill with th...
Unlock Sunshine Girl in Ironkill with this special 148Apps code Posted by Rob Rich on January 29th, 2015 [ permalink ] Robo-fighter Ironkill has been out on iOS a | Read more »
Crossroad Zombies Review
Crossroad Zombies Review By Jordan Minor on January 29th, 2015 Our Rating: :: CROSSWALKING DEADiPad Only App - Designed for the iPad Crossroad Zombies is a rough draft of a cool genre mash-up.   | Read more »
Blood Brothers 2 – Tips, Cheats, and Str...
War is hell: Is it the kind of hell you want to check out? Read our Blood Brothers 2 review to find out! Blood Brothers 2, DeNA’s follow-up to the original Blood Brothers, is an intriguing card collecting / role-playing / strategy hybrid. There’s... | Read more »
Blood Brothers 2 Review
Blood Brothers 2 Review By Nadia Oxford on January 29th, 2015 Our Rating: :: AN AGGRAVATING RELATIVEUniversal App - Designed for iPhone and iPad Blood Brothers 2 is built on a simple, solid foundation, but its free-to-play system... | Read more »
I AM BREAD, the Toast of the Town, is Ro...
Have you ever dreamt of being deliciously gluten-y? Do you feel passionate about Rye and Wheat? The guys at Bossa Studios do and that is why they are bringing I AM BREAD to iOS soon. The loafy app will feature all the new content that is being... | Read more »

Price Scanner via MacPrices.net

Intel Aims to Transform Workplace With 5th-Ge...
Intel Corporation today announced the availability of its 5th generation Intel Core vPro processor family that provides cutting-edge features to enable a new and rapidly shifting workplace. To meet... Read more
iOS App Sharalike Introduces New Instant Smar...
Sharalike slideshow and photo management software for iOS, is making it easier than ever to create shareable meaningful moments with its new instant SmartShow technology. Staying organized is a goal... Read more
Apple Becomes World’s Largest Smartphone Vend...
According to the latest research data from Strategy Analytics, as global smartphone shipments grew 31 percent annually to reach a record 380 million units in the fourth quarter of 2014. Apple became... Read more
Cut the Cord: OtterBox Resurgence Power Case...
Dead batteries and broken phones are two of the biggest issues for smartphone users today. Otterbox addresses both with the new Resurgence Power Case for Apple iPhone 6, promising to make those panic... Read more
13-inch Retina MacBook Pros on sale for up to...
B&H Photo has 13″ Retina MacBook Pros on sale for $200 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 2.6GHz/128GB Retina MacBook Pro: $1199.99 save $100 - 13″ 2.6GHz/... Read more
15-inch 2.5GHz Retina MacBook Pro on sale for...
 B&H Photo has the 15″ 2.5GHz Retina MacBook Pro on sale for $2319.99 including free shipping plus NY sales tax only. Their price is $180 off MSRP, and it’s the lowest price available for this... Read more
Back in stock: Refurbished iPod nanos for $99...
The Apple Store has Apple Certified Refurbished 16GB iPod nanos available for $99 including free shipping and Apple’s standard one-year warranty. That’s $50 off the cost of new nanos. Most colors are... Read more
Apple lowers price on refurbished 256GB MacBo...
The Apple Store has lowered prices on Apple Certified Refurbished 2014 MacBook Airs with 256GB SSDs, now available for up to $200 off the cost of new models. An Apple one-year warranty is included... Read more
New Good Management Suite Simplifies Enterpri...
Good Technology has announced the availability of the Good Management Suite, a comprehensive cross-platform solution for organizations getting started with mobile business initiatives. Built on the... Read more
15-inch 2.0GHz Retina MacBook Pro (refurbishe...
The Apple Store has Apple Certified Refurbished previous-generation 15″ 2.0GHz Retina MacBook Pros available for $1489 including free shipping plus Apple’s standard one-year warranty. Their price is... Read more

Jobs Board

Sr. Mac Expert- *Apple* Online Store - Apple...
**Job Summary** The World Wide Apple Online Store (AOS) Sales and Service team is looking for motivated, outgoing, and tech savvy individuals who want to offer Apple Read more
*Apple* Solutions Consultant- Retail Sales (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Event Director, *Apple* Retail Marketing -...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global engagement strategy and team. Delivering an overarching brand Read more
At-Home Chat Specialist- *Apple* Online Stor...
**Job Summary** At Apple , we believe in hard work, a fun environment, and the kind of creativity and innovation that only comes about when talented people from diverse Read more
SW QA Engineer - *Apple* TV - Apple (United...
**Job Summary** The Apple TV team is looking for experienced Quality Assurance Engineers with a passion for delivering first in class home entertainment solutions. **Key Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.