Open Powerplant is now up on

PowerPlant is a mature C++ framework for the Mac that has been around since the early 1990’s.
I found out today on the #macdev IRC channel
that an
open-source version
is available on
For Windows guys – this is like Microsoft making Microsoft Foundation classes open source.
Well, maybe not quite, since now there is Cocoa, but it’s pretty damned close.

You can read
the Metrowerks page on PowerPlant,
although I expect that to go away at some point.
Here are some quotes from their blurbs:

Modern application frameworks provide the initial benefit of containing robust code that
perform the common functions in a Mac OS application. Using a framework decreases
the risk of introducing errors into the application, specifically in the areas of creating and
managing the user interface, interacting with the event loop, and in any of the other areas
supported by the framework. Because many other developers have also used the
framework, those parts of your application have already been subjected to rigorous
testing before you write your first line of custom code.


PowerPlant provides a complete framework for Mac OS application development. The
first few levels of required event processing are managed totally by the application
classes, and the appearance and first level of processing for all user interface elements are
implemented fully by the associated classes.

PowerPlant also provides a visual tool for designing the User Interface, Constructor. Use
Constructor to design and layout the menus windows for your application, including the
placement and appearance of controls, edit fields, and any other interface elements
contained within the windows, then incorporate them into your program with just a few
lines of code. The simplicity of this process, especially when compared to building the
user interface programmatically, encourages the developer to experiment with variations
of the user interface until an optimum design is found.

As to that last bit, yes, the source code for the UI-building tool Constructor is included with the source.
So finally people can fix bugs that annoy them.

Now, really, this is not quite the bombshell it would have been even a year ago.
At this point, almost nobody uses PowerPlant any more, except for legacy apps that haven’t been converted over to Xcode yet.
This release should allow those people to bring PowerPlant up to date if they want, making it build on Intel among other things.
Also, anyone who doesn’t want to develop in Objective C has no other alternative for an OO framework.

So who knows, this may revive interest in PowerPlant.
Maybe someone will port it to Windows, as was done by the Starry Night guys.