TweetFollow Us on Twitter

Nov 91 Letters
Volume Number:7
Issue Number:11
Column Tag:Letters

Strip Printing

By Kirk Chase, Editor

Larry Resestein at August BAMADA

James Plamondon

Fourth Wednesday of the month at 7PM, in the Mountain View Room of Apple’s City Center Four building, at 20450 Steven’s Creek Boulevard, Cupertino

Larry Rosenstein, MacApp wizard, was the speaker at the August BAMADA meeting where he discussed a few ideas from his book, C++ Programming with MacApp. First, he discussed filtered commands, which are described in detail in Chapter 25 of his book. The goal of the filtered command mechanism is to reduce the amount of information that one must maintain in order to undo or redo a command.

Larry gave the example of a styled text document, containing hundreds of different style runs (a little bold Times, some 9-point Zapf Chancery, a dash of italic Courier, etc. -- a real ransom-note document). If the user selected all of the document’s styled text, and set it to plain Geneva 12, saving the previous state of the document -- with all of its different styles -- could take a lot of space; in the worst case, you might have to save off the entire document.

Filtered commands solve this problem. Instead of saving the pre-change data, and then altering the document in accordance with the command, the command just installs a filter into each affected piece of data which makes it LOOK as if it has been changed. In the example above, each style run object would be filtered to look like it was plain Geneva 12. To undo the command, the filter is simply removed; to redo it, the filter is reapplied.

The mechanics of the approach are beyond the scope of this summary; besides, you can find them in Larry’s excellent book. Suffice it to say that the use of such commands simplifies the implementation of Undo/Redo significantly, and reduces the storage costs associated with it, at the cost of slightly slower data access times.

After Larry shined his light on filtered commands, he moved on to streaming. Streaming is also discussed in his book (in Chapter 22), and is a major feature of MacApp 3.0. By using streams for data I/O, one can handle input and output more abstractly; one can stream to a file or to the clipboard with equal ease.

The basic idea is that the TStream class is responsible for reading and writing bytes, or aggregates of bytes, from and to “something.” TStream’s subclasses implement the abstract methods that do the reading an writing. For example, a TFileStream would implement reading and writing to a file, while a THandleStream would implement reading and writing to a memory block. A TCountingStream wouldn’t read or write anything -- it would just count the bytes that it was told to write; this is particularly useful when trying to find out if there’s enough room on a disk to hold a file, before you actually write it out (via a TFileStream).

Larry’s book describes streaming in much more detail than this, of course, and you’ll want to look into it, as streams are used extensively in MacApp 3.0.

Article missing

MacTutor

Due to an oversight on our part, the last part of Brendan Murphy's article on Modeless SFDialogs was missing. Here is a reprint of that final section.

Conclusion

After reading this article there are probably a lot of unanswered questions. These questions are left to the reader as an exercise (I always hated that in college). I’m not going to produce a Think C version or a MacApp version. I leave this honor to some hearty soul out there. I will release a maintenance version if enough bugs or deficiencies are brought to my attention. My hope for this piece of software is that it will someday be incorporated into Apple’s system software (7.x or 8.x) and thus make this article a moot exercise for future programmers.

In the future, I plan to write more articles on TCL and perhaps MacApp. I am already “cooking up” some ideas to remove some of the short comings of TCL, but I have not yet decided which idea to pursue. Half the battle is coming up with the idea and half the battle is sticking with the idea and half the battle is implementing the idea. Yes, that adds up to 3/2 which goes to show that anything worth doing, is more work than you thought.

A Problem Stripping

Deborah E. Meadow

Cormetrics Medical Systems, Inc.

61 Barnes Park Road North

Wallingford, CT 06492-0333

(203) 265-5631

Now that the title has caught your attention, here is somthing interesting. While a the Boston MacWorld, Deborah Meadow approached me with an unsual problem. From the above address, you can see that she works for a medical group. Her problem involves printing. Some things such as EKG strips are printed in a continuous fashion, i.e. they are not spooled by the page as Mac printing is usually done. What she would like is help in creating, hopefully, a general purpose driver to do real-time, strip printing. If you have an idea, please get in touch with her at the above address.

Cheshire Keeps on Smiling

Cheshire Grin Productions Ltd.

2145 Sherobee Rd., Ste. 43

Mississauga, Ontario, Canada L5A 3G8

Cheshire Grin has just added two new additions to their Stack Enhancers product. The first addition is the Browser Palette. This allows the user/developer to navigate cards quickly and do card management, such as renaming cards; its immediate benefit is navigation for incomplete stacks. The second addition to Stack Enhancers is the Search Palette. This palette allows you to search for text on a particular stack-great for keeping a list of cards that meet the search criterea. Contact Cheshire Grin for more information.

Prospective International Software Developers

The Software Toolworks

60 Leveroni Court

Novato, CA 94949

(415) 883-3000

Planning on making a trip overseas to a trade show or just curious about the world around you? The Software Toolworks has the product for you, World Atlas. This product puts the atlas on your computer. It comes complete with over 250 detailed maps in either black & white or color. There is also a database covering information such as population, climate, national holidays, and travel documents. Sort of a one stop shop in world travel information.

BitMap Error

Kirk Chase

MacTutor

I would like to point out an error in some code published in MacTutor, November 1990 ("Special Effects") and June 1991 ("Kolorize Your B&W Application"). Basically the code in question is the offscreen bitmap allocation function used in both articles. The offending line in the procedure NewBitMap is

bm->baseAddr=NewPtr(bm->rowBytes *(long (r->right - r->left));

This assumes a height the same size as the width. Correct it to the following:

bm->baseAddr=NewPtr(bm->rowBytes *(long (r->bottom - r->top));

Thanks to Randy Frank for pointing this out.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Suitcase Fusion 7 18.2.4 - Font manageme...
Suitcase Fusion 7 is the creative professional's font manager. Every professional font manager should deliver the basics: spectacular previews, powerful search tools, and efficient font organization... Read more
SoftRAID 5.6.1 - High-quality RAID manag...
SoftRAID allows you to create and manage disk arrays to increase performance and reliability. SoftRAID allows the user to create and manage RAID 4 and 5 volumes, RAID 1+0, and RAID 1 (Mirror) and... Read more
BetterTouchTool 2.25 - Customize Multi-T...
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
Google Chrome 59.0.3071.115 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
Google Chrome 59.0.3071.115 - Modern and...
Google Chrome is a Web browser by Google, created to be a modern platform for Web pages and applications. It utilizes very fast loading of Web pages and has a V8 engine, which is a custom built... Read more
SoftRAID 5.6.1 - High-quality RAID manag...
SoftRAID allows you to create and manage disk arrays to increase performance and reliability. SoftRAID allows the user to create and manage RAID 4 and 5 volumes, RAID 1+0, and RAID 1 (Mirror) and... Read more
Suitcase Fusion 7 18.2.4 - Font manageme...
Suitcase Fusion 7 is the creative professional's font manager. Every professional font manager should deliver the basics: spectacular previews, powerful search tools, and efficient font organization... Read more
BetterTouchTool 2.25 - Customize Multi-T...
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
WhiteCap 6.7.1 - Visual plug-in for iTun...
WhiteCap is a sleek and sophisticated music visualizer and screensaver that features futuristic, wireframe mesh visuals with dynamic backgrounds and colors. WhiteCap contains thousands of visual... Read more
DiskMaker X 6.0 rc5 - Make a bootable OS...
DiskMaker X (was Lion DiskMaker) helps you to build a bootable drive from the official OS X installer app (the one you download from the Mac App Store). It detects the OS X Install program with... Read more

Latest Forum Discussions

See All

This War of Mine gets a new ending and m...
This War of Mine just got a big new update, featuring free DLC that adds a new ending to the game, among other exciting changes. The update is celebrating the game's two-year release anniversary. Apart from the new ending, which will be quite... | Read more »
Summon eight new heroes in Fire Emblem H...
Nintendo keeps coming at us with Fire Emblem Heroes updates, and it doesn't look like that trend is stopping anytime soon. The folks behind the game have just announced the new War of the Clerics Voting Gauntlet, expected to start next Tuesday. [... | Read more »
The best deals on the App Store this wee...
iOS publishers are pulling out all the stops this week -- there's a huge number of seriously great games at discounted prices this week. Let's not waste any time and get right down to business. [Read more] | Read more »
The House of da Vinci (Games)
The House of da Vinci 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: Enter The House of Da Vinci, a new must-try 3D puzzle adventure game. Solve mechanical puzzles, discover hidden... | Read more »
Solve the disappearance of history’s gre...
Blue Brain Games invites you to indulge in an immersive hands-on 3D puzzle adventure in similar vein to The Room series, with its debut release The House of Da Vinci. Set during the historic period of the Italian Renaissance (when Leonardo himself... | Read more »
Age of Rivals (Games)
Age of Rivals 3.3 Device: iOS Universal Category: Games Price: $.99, Version: 3.3 (iTunes) Description: Deep civilization-building strategy in a fast-paced card game! | Read more »
Panthera Frontier (Games)
Panthera Frontier 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: | Read more »
Angry Birds Evolution beginner's gu...
Angry Birds changes things up a fair bit in its latest iteration, Angry Birds Evolution. The familiar sling-shot physics mechanics are still there, but the game now features team-based gameplay, RPG elements, and a new top-down view. With all of... | Read more »
Sega Forever is for the retro game fans
Sega is launching a new retro games service titled Sega Forever, in a move that's sure to delight games enthusiasts with a bit of nostalgia. Sega's releasing five classic games for free. The titles include Sonic the Hedgehog, Phantasy Star II,... | Read more »
The Little Acre (Games)
The Little Acre 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: | Read more »

Price Scanner via MacPrices.net

13-inch 1.8GHz/256GB MacBook Air on sale for...
B&H Photo has the updated 2017 13″ 1.8GHz/256GB MacBook Air (MQD42LL/A) in stock and on sale for $1129 including free shipping plus NY & NJ tax only. Their price is $70 off MSRP. Read more
27-inch 3.4GHz iMac on sale for $1699, save $...
B&H Photo has the new 2017 27″ 3.4GHz iMac (MNE92LL/A) in stock and on sale for $1699 including free shipping plus NY & NJ sales tax only. Their price is $100 off MSRP. Read more
21-inch 2.3GHz iMac on sale for $1049, save $...
B&H Photo has the new 2017 21″ 2.3GHz iMac (MMQA2LL/A) in stock and on sale for $1049 including free shipping plus NY & NJ tax only. Their price is $50 off MSRP. Read more
ABBYY TextGrabber 6 for iOS Implements Instan...
ABBYY has announced the release of TextGrabber 6.0.0, an important feature update to the company’s productivity app developed for iOS and Android devices. TextGrabber 6.0 now offers Real-Time... Read more
vPhone, First Smartphone That Can’t Be Lost,...
Austin, Texas based Hypori has introduced the vPhone, a virtual smartphone that affords every business user the benefits of separate work and personal phones, conveniently delivered on a single... Read more
Save this weekend with 2016 refurbished MacBo...
Apple has dropped prices on Certified Refurbished 2016 15″ and 13″ MacBook Pros by as much as $590 off original MSRP. An Apple one-year warranty is included with each model, and shipping is free: -... Read more
New 27-inch 3.4GHz iMac on sale for $1699, sa...
MacMall has the new 2017 27″ 3.4GHz iMac (MNE92LL/A) in stock and on sale for $1699 including free shipping. Their price is $100 off MSRP. Read more
Clearance 2016 MacBook Pros available for up...
B&H Photo has clearance 2016 13″ and 15″ MacBook Pros in stock today and on sale for up to $400 off original MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: - 15″ 2.7GHz... Read more
Apple Ranks 9th In comScore Top 50 U.S. Digit...
comScore, Inc. has released its monthly ranking of U.S. online activity at the top digital media properties for May 2017 based on data from comScore Media Metrix Multi-Platform. * Entity has... Read more
10.5-inch iPad Pros available for up to $20 o...
B&H Photo has the new 2017 10.5″ iPad Pros available for up to $20 off MSRP including free shipping plus NY & NJ sales tax only: - 64GB iPad Pro WiFi: $649 - 256GB iPad Pro WiFi: $749 - 512GB... Read more

Jobs Board

*Apple* News Product Marketing Mgr., Publish...
…organizational consensus on strategy and vision for publisher tools, authoring, and Apple News Format.Carries this strategy and vision across the organization to 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
Security Data Analyst - *Apple* Information...
…data sources need to be collected to allow Information Security to better protect Apple employees and customers from a wide range of threats.Act as the subject matter Read more
Lead *Apple* Solutions Consultant - Apple I...
…integrity, and trust.Success Metrics/Key Performance Indicators:Quantitative* Year over Year growth in Apple Product and Beyond the Box sales in the assigned Point of Read more
*Apple* Solutions Consultant till v%u00E5r...
…ethics, integrity, and trust.Success Metrics/Key Performance Indicators:QuantitativeYear over Year growth in Apple Product and Beyond the Box sales in the assigned Point Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.