Appearance Manager

In the pre-Mac OS X version of the Macintosh operating system, the Appearance Manager controlled the overall look of the Mac GUI widgets and supported several themes. The Appearance Manager was originally developed for Apple's failed Copland project, but with the cancellation of this project the system was moved into newer versions of the Mac OS, notably Mac OS 8 and 9. The current version of the operating system, Mac OS X, no longer directly supports the Appearance Manager, which can be considered "dead".

The Appearance Manager was implemented as an abstraction layer between the Control Manager and QuickDraw. Previously, controls made direct QuickDraw calls to draw user interface elements such as buttons, scrollbars, window title bars, etc. With Appearance, these elements were abstracted into a series of APIs that would draw the item as a distinct entity on behalf of the client code, thus relieving the Control Manager of the task. This extra level of indirection allowed the system to support the concept of switchable themes, since client code would simply request the image of an interface element (a button or scroll bar, for example) and draw its appearance. The Appearance Manager remains as part of Carbon, but switchable themes are no longer supported in Mac OS X.

Typography

By default, the Appearance Manager used a font called Charcoal to replace the similar Chicago typeface that had been used in earlier versions of the Mac OS. A number of additional fonts were also provided, Capitals, Gadget, Sand, Techno, and Textile. These fonts needed to provide not only the regular letters and symbols of any other font, but also those specific to the Mac operating system, such as the Command key symbol, unicode|⌘. Normally fonts were displayed at 12 points.

The Appearance Manager also applied anti-aliasing to type displayed on the screen above a certain size, by default 12 points. This improved the overall look of the text by reducing certain distortion artifacts intrinsic to computer screens.

Appearance Themes

to Apple Platinum and the type code 'thme' to identify if a file should act like an Appearance Theme.

Apple widely demonstrated two Appearance Themes which override Apple Platinum, Hi-Tech and Gizmo. Hi-Tech is based on a shades-of-black color scheme that made the interface look like a piece of stereo equipment. Gizmo is a "kids" interface, using lots of bright colors and "wiggly" interface elements. Both changed every single element of the overall GUI leaving no trace of Apple Platinum. A third theme was later introduced, Drawing Board, developed at Apple Japan. This theme uses elements that make the interface look like it has been drawn in pencil on a drafting-board, including small "pencil marks" around the windows, a barely-visible grid on the desktop, and "squarish" elements with low-contrast.

Platinum was also used on several versions of OpenStep while it was in the process of being turned into Mac OS X. In particular, both Rhapsody and, the final version of it, which was called Mac OS X Server 1.0, and also Mac OS X Developer Previews up to DR2 used a Platinum-based UI. An updated and more powerful version of the Appearance Manager was used for Carbon applications in Mac OS X even after Apple made the transition to Aqua. The Extras.rsrc file is an updated version of an Appearance Theme that is compatible with the newer Appearance Manager. As of Mac OS X version 10.3, 'layo' data is no longer used even for Carbon applications, so the existence of the Appearance Manager can no longer be confirmed.

imilar products

Shareware products existed that provided some or all of the functionality offered by Appearance Manager before the Control Panel became part of the Mac operating system. These included Church Windows and Décor, both Control Panels that set the desktop pattern to a picture; and WindowShade, a Control Panel that caused application windows to "roll up" when the title bar was double-clicked. Kaleidoscope was an application that applied system-wide schemes in a similar way to the Appearance Manager. Aaron was an Extension that applied a similar Platinum look to that used in Mac OS 8, though in this case it was mimicking the ill-fated Copland operating system upon which Mac OS 8's styling was based, rather than Mac OS 8 itself.

Although rendered largely obsolete once Mac OS 8 was released, these add-ons could be used on Macs running earlier versions of the operating system to provide at least some of the Mac OS 8 'look and feel'. Kaleidoscope was not rendered obsolete when Appearance Themes were made possible in Mac OS 8.5. "K-Schemes" were much easier to create than genuine Appearance Themes for various reasons. Scheme tools were widely available while Theme tools were extremely rare and difficult to use. The format of Schemes is less complicated than that of Themes. Because of these factors, development of Themes was extremely limited - in most cases Themes were just slightly hacked versions of the three Themes made by Apple. Kaleidoscope was only rendered obsolete with the transition to Mac OS X.

Examples of Appearance Themes

External links

* [http://www.macintouch.com/m85_themes.html Mac OS 8.5 Special Report: Themes and Appearances]