TweetFollow Us on Twitter

Apr 96 Factory Floor
Volume Number:12
Issue Number:4
Column Tag:From The Factory Floor

From the Factory Floor

By Dave Mark

In this month’s Factory Floor, we’ll meet Greg Dow. Greg designed and wrote PowerPlant, the next generation framework from Metrowerks. Before we get to the interview, I wanted to take a sec and thank Jim Trudeau for all his help in putting this interview together. Cognac and cigars on me at WWDC, Jim!

Dave: Greg, since not all of our readers have a background in object programming, let’s start things off by defining a few terms. What is the difference between a class library and a framework?

Greg: People often use the terms interchangeably. However, I think of a class library as a collection of utilities and a framework as a structure for building programs.

With a class library, you are in control. You design the program structure and use library classes where convenient. For example, you can use the ANSI C++ streams class library to handle file I/O.

With a framework, the framework is in control. You usually start with a “do nothing” program provided by the framework and add your own code. The framework calls your code at the appropriate time.

PowerPlant is a framework, but it also has families of utility classes that you can use independently.

Dave: Why would a C programmer want to move to C++ and PowerPlant? What are the advantages?

Greg: Using PowerPlant lets you build upon code written by other programmers. It’s code that you don’t have to write yourself. PowerPlant classes handle mundane tasks such as menu and window management, as well as more advanced features such as Apple events and threads. By not having to start from scratch, you have more time to concentrate on the unique features of your program.

Another big advantage is Constructor, which lets you graphically lay out the visual elements of your PowerPlant programs. PowerPlant can create a window and its contents from information edited in Constructor, so it’s possible to create a program that displays items such as scrolling pictures, text, and buttons without ever writing a line of code.

Dave: Once someone has learned the basics of C++ and object programming, how do they pick up on PowerPlant?

Greg: The first thing everyone should do is read The PowerPlant Book, which is part of the Inside PowerPlant for CW8 manual that comes with CW8. This book, written by Jim Trudeau, is an excellent guide to understanding and using PowerPlant.

After that, they should start using PowerPlant. Look over the sample programs. Run the samples and use the source debugger to single-step through some of the code to follow the flow of control. For example, set a breakpoint in the main event loop, then hit a key and follow the resulting sequence of calls to see how PowerPlant handles it.

Finally, talk with other people who use PowerPlant by getting a modem and an Internet account. Read the Usenet newsgroup comp.sys.mac.programmer.codewarrior. (A new group, comp.sys.oop.powerplant, will probably form soon.) Metrowerks also has an active forum on America Online. And join the PowerPlant Dream Team.

Dave: What exactly is the PowerPlant Dream Team? What do they do? How do you go about joining?

Greg: The PowerPlant Dream Team is an organization of developers interested in learning PowerPlant in a team-based environment. It started as a study group formed by Stephen Jovanovic, but has grown to over 200 people. A small subset of the PP Dream Team wrote an LNewTextEdit class that supports styled text and drag-and-drop editing. Very cool. To find out more about the PP Dream Team, visit their Web page at: http://petrified.cic.net/powerplant-dt/

Dave: Tell me about the PowerPlant architecture.

Greg: One of my favorite toys is Lego™ blocks. You can build complex structures by combining simple parts. PowerPlant follows this approach by using a mixin architecture, where the base classes are relatively simple, and subclasses use multiple inheritance to combine features.

For example, the EditField class multiply inherits from Pane (so it can draw and handle mouse clicks), Commander (so it can handle keystrokes and menu commands), and Periodical (so it gets time during the event loop to flash the insertion point).

I also tried to eliminate dependencies between classes so that you can use them separately. In particular, PowerPlant is not just an application framework. You can use PowerPlant to build code resources such as HyperCard XCMDs and control panels, or even integrate PowerPlant classes into existing procedural programs.

Dave: What is your favorite part of PowerPlant?

Greg: Other than the overall design, my favorite feature of PowerPlant is the Drag Manager support. Drag and drop is cool, and it’s one of the better implemented features in the Mac OS. The API is clean and simple. It took me only two days (and three classes) to implement all the basic support.

Dave: Tell me about your life before Metrowerks.

Greg: I have a Bachelor’s degree from MIT in chemical engineering, and I spent a few years at UC Berkeley working on a Ph.D., also in chemical engineering, that I never completed. My thesis research was computer modeling of coal gasification reactors, and I did a lot of scientific programming in FORTRAN.

During that time, I became more interested in programming than in chemical engineering, so I started taking computer science classes. In July 1987, I bought my first personal computer, a Mac SE. A few months later, I dropped out of school to devote my time to learning Mac programming.

One of my first projects was writing a generic application shell. I kept tinkering with this shell, and it eventually turned into version 1.0 of the THINK Class Library (TCL), which Symantec shipped with THINK C in July 1989.

Dave: How did you get hooked up with Metrowerks? Did Greg Galanos recruit you? Was the company already building CodeWarrior when you started work on PowerPlant?

Greg: My first contact with Metrowerks was actually with Jean Belanger, sometime before the MacWorld Expo in January 1992. I lead the Programmers Group at BMUG (Berkeley Macintosh Users Group), and Jean called up looking for some volunteers to staff his booth at the show. At the time, Metrowerks was selling Pascal and Modula 2 compilers for the education market.

I never actually met anyone from Metrowerks then, but a year later John McEnerney asked me if I was interested in writing a new C++ framework for some little Canadian company. John is the PowerPC Compiler Architect for Metrowerks, and he worked at Symantec when I wrote TCL 1.0.

I met with Greg Galanos and started working on PowerPlant in March 1993. Codewarrior as we know it did not exist. There was a prototype C compiler and environment. It fit on a floppy disk.

Dave: A lot of people ask about cross-platform development using PowerPlant. I know that the Microsoft Foundation Classes (MFC) are the de facto standard on the Windows side. What’s the best way to get a PowerPlant-based application ported to run under Windows?

Greg: I know that a lot of people are interested in developing programs that run on both the Mac and Windows. However, PowerPlant is a Mac-only framework. Metrowerks has no intention of developing a Windows version of PowerPlant.

To port code to Windows, I recommend that people investigate Mac2Win from Altura Software. The Mac2Win libraries emulate the Mac Toolbox on Windows. Metrowerks is using these libraries to port portions of the CodeWarrior environment to Windows.

Dave: What are your future plans for PowerPlant?

Greg: My future work with PowerPlant will concentrate on three major areas: (1) Visual programming; (2) OpenDoc; and (3) Copland.

Right now, you can specify the static layout of interface elements using PowerPlant Constructor. Future versions of Constructor will let you specify runtime relationships between objects. For example, adding Attachments to Panes and linking Broadcasters to Listeners.

If you know what you’re doing, you can use PowerPlant today to develop both OpenDoc parts and OpenDoc container applications. In fact, a few programmers (besides me) have already done so. However, it’s not easy. Future versions of PowerPlant will make it as easy to create an OpenDoc part as it is to create a stand-alone application.

Copland, the next major version of the Mac OS, will provide many new capabilities and interface elements. I intend to keep PowerPlant on the leading edge of Mac development by supporting these new features as soon as possible.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Tidy Up 5.3.7 - Find duplicate files and...
Tidy Up is a full-featured duplicate finder and disk-tidiness utility. Features: Supports Lightroom: it is now possible to search and collect duplicates directly in the Lightroom library. Multiple... Read more
Pinegrow 5.97 - Mockup and design web pa...
Pinegrow (was Pinegrow Web Designer) is desktop app that lets you mockup and design webpages faster with multi-page editing, CSS and LESS styling, and smart components for Bootstrap, Foundation,... Read more
BlueStacks 4.210.0 - Run Android applica...
BlueStacks App Player lets you run your Android apps fast and fullscreen on your Mac. Feature comparison chart How to install Bluestacks on your Mac Go to MacUpdate and click the green "Download"... Read more
WhatsApp 2.2027.10 - Desktop client for...
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
Art Text 4.0.1 - $29.99
Art Text is graphic design software specifically tuned for lettering, typography, text mockups and various artistic text effects. Supplied with a great variety of ready to use styles and materials,... Read more
Adobe Dreamweaver CC 2020 20.2 - Build w...
Dreamweaver CC 2020 is available as part of Adobe Creative Cloud for as little as $20.99/month (or $9.99/month if you're a previous Dreamweaver customer). Adobe Dreamweaver CC 2020 allows you to... Read more
Adobe Acrobat DC 20.009.20074 - Powerful...
Acrobat DC is available only as a part of Adobe Creative Cloud, and can only be installed and/or updated through Adobe's Creative Cloud app. Adobe Acrobat DC with Adobe Document Cloud services is... Read more
beaTunes 5.2.10 - Organize your music co...
beaTunes is a full-featured music player and organizational tool for music collections. How well organized is your music library? Are your artists always spelled the same way? Any R.E.M. vs REM?... Read more
DiskCatalogMaker 8.1.5 - Catalog your di...
DiskCatalogMaker is a simple disk management tool which catalogs disks. Simple, light-weight, and fast Finder-like intuitive look and feel Super-fast search algorithm Can compress catalog data for... Read more
Meteorologist 3.4.1 - Popular weather ap...
Meteorologist is a simple interface to weather provided by weather.com. It provides the ability to show the weather in the main menu bar, displaying more detail in a pop-up menu, whose contents are... Read more

Latest Forum Discussions

See All

Steam Link Spotlight - Disco Elysium
Steam Link Spotlight is a feature where we look at PC games that play exceptionally well using the Steam Link app. Our last entry was Signs of the Sojourner Read about how it plays using Steam Link over here. | Read more »
Distract Yourself With These Great Mobil...
There’s a lot going on right now, and I don’t really feel like trying to write some kind of pithy intro for it. All I’ll say is lots of people have been coming together and helping each other in small ways, and I’m choosing to focus on that as I... | Read more »
Pokemon Go's July Community Day wil...
Pokemon Go developers have announced the details concerning the upcoming Gastly Community Day. This particular event was selected by the players of the game after the Gas Pokemon came in second place after a poll that decided which Pokemon would... | Read more »
Clash Royale: The Road to Legendary Aren...
Supercell recently celebrated its 10th anniversary and their best title, Clash Royale, is as good as it's ever been. Even for lapsed players, returning to the game is as easy as can be. If you want to join us in picking the game back up, we've put... | Read more »
Detective Di is a point-and-click murder...
Detective Di is a point-and-click murder mystery set in Tang Dynasty-era China. You'll take on the role of China's best-known investigator, Di Renjie, as he solves a series of grisly murders that will ultimately lead him on a collision course with... | Read more »
Dissidia Final Fantasy Opera Omnia is se...
Dissidia Final Fantasy Opera Omnia, one of Square Enix's many popular mobile RPGs, has announced a plethora of in-game events that are set to take place over the summer. This will include several rewards, Free Multi Draws and more. [Read more] | Read more »
Sphaze is a neat-looking puzzler where y...
Sphaze is a neat-looking puzzler where you'll work to guide robots through increasingly elaborate mazes. It's set in a visually distinct world that's equal parts fantasy and sci-fi, and it's finally launched today for iOS and Android devices. [... | Read more »
Apple Arcade is in trouble
Yesterday, Bloomberg reported that Apple is disappointed in the performance of Apple Arcade and will be shifting their approach to the service by focusing on games that can retain subscribers and canceling other upcoming releases that don't fit... | Read more »
Pixel Petz, an inventive platform for de...
Pixel Petz has built up a sizeable player base thanks to its layered, easy-to-understand creative tools and friendly social experience. It revolves around designing, trading, and playing with a unique collection of pixel art pets, and it's out now... | Read more »
The King of Fighters Allstar's late...
The King of Fighters ALLSTAR, Netmarble's popular action RPG, has once again been updated with a plethora of new content. This includes battle cards, events and 21 new fighters, which increases the already sizeable roster even more. [Read more] | Read more »

Price Scanner via MacPrices.net

Clearance 2019 13″ 2.4GHz/256GB MacBook Pro o...
B&H Photo has dropped their price on the clearance 2019 13″ 2.4GHz/256GB Quad-Core Silver MacBook Pro by $500 off Apple’s original MSRP to a new low of only $1299. Expedited shipping is free to... Read more
$219 Apple AirPods Pro are back at Verizon, s...
Verizon has Apple AirPods Pro on sale again for a limited time for $219.99 on their online store. Their price is $30 off Apple’s MSRP, and it’s the lowest price we’ve seen for AirPods Pro. Available... Read more
Apple’s $779 13″ MacBook Air deal returns to...
Apple has clearance, Certified Refurbished, 2019 13″ MacBook Airs available again starting at $779. Each MacBook features a new outer case, comes with a standard Apple one-year warranty, and is... Read more
$200 13″ MacBook Pro discounts are back at Am...
Amazon has 2020 13″ 2.0GHz MacBook Pros on sale again today for $150-$200 off Apple’s MSRP. Shipping is free. Be sure to purchase the MacBook Pro from Amazon, rather than a third-party seller, and... Read more
Deal Alert! Apple AirPods with Wireless Charg...
Sams Club has Apple AirPods with Wireless Charging Case on sale on their online store for only $149.98 from July 6, 2020 to July 9, 2020. Their price is $50 off Apple’s MSRP, and it’s the lowest... Read more
Xfinity Mobile promo: Apple iPhone XS models...
Take $300 off the purchase of any Apple iPhone XS model at Xfinity Mobile while supplies last. Service plan required: – 64GB iPhone XS: $599.99 save $300 – 256GB iPhone XS: $749.99 save $300 – 512GB... Read more
New July 2020 promo at US Cellular: Switch an...
US Cellular has introduced a new July 2020 deal offering free 64GB Apple iPhone 11 smartphones to customers opening a new line of service. No trade-in required, and discounts are applied via monthly... Read more
Apple offers up to $400 Education discount on...
Apple has launched their Back to School promotion for 2020. They will include one free pair Apple AirPods (with charging case) with the purchase of a MacBook Air, MacBook Pro, iMac, or iMac Pro (Mac... Read more
July 4th Sale: Woot offers wide range of Macs...
Amazon-owned Woot is blowing out a wide range of Apple Macs and iPads for July 4th staring at $279 and ranging up to just over $1000. Models vary from older iPads and 11″ MacBook Airs to some newer... Read more
Apple Pro Display XDR with Nano-Texture Glass...
Abt Electronics has Apple’s new 32″ Pro Display XDR model with the nano-texture glass in stock and on sale today for up to $144 off MSRP. Shipping is free: – Pro Display XDR (nano-texture glass): $... Read more

Jobs Board

Physical Therapist Assistant - *Apple* Hill...
Physical Therapist Assistant - Apple Hill Rehab - Full Time Tracking Code 62519 Job Description General Summary: Under the direct supervision of a licensed Physical Read more
Operating Room Assistant, *Apple* Hill Surg...
Operating Room Assistant, Apple Hill Surgical Center - Full Time, Day Shift, Monday - Saturday availability required Tracking Code 62363 Job Description Operating Read more
Perioperative RN - ( *Apple* Hill Surgical C...
Perioperative RN - ( Apple Hill Surgical Center) Tracking Code 60593 Job Description Monday - Friday - Full Time Days Possible Saturdays General Summary: Under the Read more
Product Manager, *Apple* Commercial Sales -...
Product Manager, Apple Commercial Sales Austin, TX, US Requisition Number:77652 As an Apple Product Manager for the Commercial Sales team at Insight, you Read more
*Apple* Mac Product Engineer - Barclays (Uni...
Apple Mac EngineerWhippany, NJ Support the development and delivery of solutions, products, and capabilities into the Barclays environment working across technical Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.