Appearance Manager
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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 bundled with Mac OS 8 and 9. However, Appearance Manager is also available free as part of a downloadable SDK for System 7.[1] 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.
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[edit] 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, ⌘. 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.
[edit] Appearance Themes
The default look and feel of the Appearance Manager in the Mac OS 8 - 9 Era is Apple Platinum, which was intended to be the primary GUI for Copland. Platinum retains many of the shapes and positions of elements from System 7 and earlier, like window control widgets and buttons and Charcoal is the associated default system font. However, various shades of grey are used extensively throughout the interface, as opposed to previous interfaces which are mostly black and white. Contrary to popular belief, Apple Platinum is technically not an Appearance Theme and does not contain any theme elements. The Platinum interface is embedded into the Mac OS System File so no Appearance Theme is necessary. There is an Apple Platinum file in the System Folder which acts as a stub, but no functional theme elements can be embedded into it. Customizable palettes ('clut' resources) are used for progress bars, scroll thumbs, slider tabs and menu selections in Apple Platinum and this unique option is not available to real themes. The Appearance Manager uses the type code 'pltn' to identify if a file should act like a palette modification stub 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. Although none of these themes were included with a released version of Mac OS, the files can be copied from the pre-release versions that contained them and successfully used on retail versions.
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.
[edit] Similar 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 (which by that time had been purchased by Apple and bundled with System 7,) a Control Panel that caused application windows to “roll up” when the title bar was double-clicked. Kaleidoscope was an extremely popular extension and control panel that applied system-wide schemes in a similar way to the later Appearance Manager. Aaron was a simpler version of Kaleidoscope and its forerunner; it only applied a Platinum look similar to that later used in Mac OS 8, though in this case for use with System 7 systems, in anticipation of the release of the ill-fated System 8 codenamed Copland.
When the Appearance Manager's theming support was first announced, the team responsible for it even demonstrated an automatic tool specifically designed to convert the tens of thousands of existing Kaleidoscope scheme files into Appearance Manager-compatible theme files.
Kaleidoscope was not rendered obsolete when 3rd-party Appearance Themes were natively supported in Mac OS 8.5 because Apple had largely abandoned the idea of a themeable Mac OS by that time, withholding their own themes, offering little documentation or support for the Appearance Manager, and sometimes even threatening 3rd-party authors. As a result, Scheme creation tools were widely available while Theme tools were extremely rare and difficult to use, the format of Schemes continued to evolve while that of Themes remained unmaintained, and Kaleidoscope was only rendered obsolete with the transition to Mac OS X.
