Aqua (user interface)

Aqua

Cocoa controls, all a part of Aqua, from Mac OS X 10.6.
Developer(s)	Apple Inc.
Initial release	January 2000
Development status	Active
Operating system	Mac OS X
Available in	Multilingual
Type	Desktop environment
License	Proprietary EULA
Website	Apple Mac OS X Aqua Human Interface Guidelines

Aqua is the GUI and primary visual theme of Apple Inc.'s Mac OS X operating system. It is based around the theme of water, as its name suggests, with droplet-like elements and liberal use of translucency and reflection effects. Steve Jobs noted Aqua's glossy aesthetic: "One of the design goals was when you saw it you wanted to lick it."

The Aqua theme and user interface was first introduced at the January 2000 Macworld Conference & Expo in San Francisco. Aqua's first appearance in a commercial product was in the July 2000 release of iMovie 2.

Aqua design elements make up the appearance of most Mac OS X applications. Its goal is to "incorporate color, depth, translucence, and complex textures into a visually appealing interface" in Mac OS X applications. Although Aqua is the entire user interface, two notable features of Aqua are gel-like buttons (such as the ones colored red, yellow, and green that control the windows), and a Dock, which facilitates the launching of and navigation between applications.

Aqua is the successor to Platinum, which was used in Mac OS 8, Mac OS 9 and Mac OS X Server 1.2.

Evolution

The first version of the Aqua GUI, from Mac OS X Public Beta. It differs vastly from the GUI of Mac OS 9 with glass-like elements and a Dock, among other things, although the Apple reverted to its traditional position on the left-hand side of the menu bar for the final release of OS X 10.0.

Much of Aqua's original design resembles the translucent two-tone look of Apple's contemporary hardware. In 2003 and 2004, Apple moved to the use of brushed metal in their industrial design (such as with the aluminum Apple Cinema Displays); in Mac OS X Panther, Aqua changed accordingly, incorporating the additional brushed metal look while deemphasizing the pinstripe backgrounds and transparency effects. This somewhat inconsistent mix of interface styles has been controversial among the Mac OS X user community. Apple replaced these inconsistent window themes with the introduction of Mac OS X Leopard. Starting with Leopard, the brushed metal look has been phased out, in favor of white inactive windows and gradient grey active windows.

Mac OS X 10.2 (Jaguar)

Jaguar brought with it flatter interface elements, such as new buttons and drop-down menus, as well as reducing the transparency to tone down the pinstripes in windows and menus. These trends would continue in further Mac OS X releases.

The Panther version of the Aqua GUI shows several changes, most notably brushed metal.

Mac OS X 10.3 (Panther)

In Mac OS X Panther, brushed metal was fused to the heart of the Macintosh: the Finder. New buttons were made to appear sunken into their surroundings, following a general trend of more flattened interface elements in the operating system. The traditional pinstripes were replaced with a much subtler theme, most notably in the menu bar, and the use of transparency was again reduced (for example in the title bars of inactive windows). Tabs also changed; they were made flatter and the whole tab area was sunken rather than raised. Tab buttons were centered on the top border of the tab area. New icons appeared across the system, including a new flatter, glossier Finder icon and a new System Preferences icon.

Mac OS X 10.4 (Tiger)

Tiger brought more subtle changes, including the Unified titlebar scheme. Pinstripes were now removed from the menu bar entirely, replaced with a new glossy look. Tabs were altered to appear as normal segmented buttons. The Apple menu icon was toned down to a more matte appearance and the new Spotlight search utility is permanently bound to the very right of the menu bar in the same color and gradient of the Apple menu.

The Aqua GUI in Mac OS X Leopard. Among the changes are a gradient window style and a new Dock and menu bar.

Mac OS X 10.5 (Leopard) and Mac OS X 10.6 (Snow Leopard)

In Leopard, several changes have been made to the user interface. The Dock was made to look more three dimensional, with a reflective “floor” for icons to sit on and icon labels having a semi-transparent background. Active applications are no longer indicated by a black triangle, but now by a glowing blue dot. The dividing line between applications and other Dock items now resembles a pedestrian crossing instead of a simple line. The dock is reflective of all elements on the screen except for the mouse cursor. “Stacks” are groups of files which can be stored in the Dock, and fan out when clicked.

The Dock is black translucent with a white border and rounded corners when placed on the sides, but it retains a 2D form of its new dividing line. The 2D form can also be applied to the default bottom Dock position with third-party utilities or by running a Terminal command to update a system configuration file.

On Macs with a Core Image–capable graphics card installed, the menu bar at the top of the screen can optionally be semi-transparent. This includes all Intel Macs and PowerPC G5s, as well as some later PowerPC G4s. Graphic card upgrades are also supported. Contextual menus are now slightly rounded, like the corners of windows.

The drop shadow of the active window is now greatly enlarged for emphasis. Inactive windows are less prominent for greater contrast between active and inactive windows. Title bars are a darker shade of grey, and all toolbars now use a darker “Unified” scheme. Brushed metal is no longer present, and has been replaced instead by a white “plastic” gradient scheme. Many windows now have minimal borders or none at all. Pinstripes in window backgrounds have now been completely removed. Sheets are now semi-transparent as well as blurring the area behind them for greater legibility.

Numerous icons have been changed, including a set of new folder icons, a new System Preferences icon and an updated Terminal icon, and all main icons have been redrawn in a high-resolution 512-by-512 size for sharper viewing in Quick Look and Cover Flow.

The default background image has also been changed to a purple aurora superimposed over a star field instead of the fluid abstract blue designs in prior versions of OS X.

Mac OS X 10.7 (Lion)

With Mac OS X Lion, many changes have taken place. The aqua scroll bars are traded for iOS-style ones. Push Buttons are square, similar to Mac OS 8 and 9, but still keep their Aqua look. Traffic light windows controls have been shrunk. Many elements that have previously been a brighter blue such as highlighted buttons, tabs, loading bars, and switches are less pronounced and not as saturated, giving them a flatter, more consistent look. The window background is slightly brighter. Round Textured buttons are transparent. Window corners have been rounded. Windows in Lion can also be in a "Full Screen" mode - on some applications, the window can take up the whole monitor space.

OS X 10.8 (Mountain Lion)

The user interface in OS X Mountain Lion, as far as buttons and windows are concerned, essentially remains unchanged from that of Lion, except for a change in the Dock's appearance. The Dock now has a frosted glass style, with rounded corners, a new separator, and blurred icon reflections. This is the first major change to the Dock's appearance since 10.5 Leopard.

Windows applications

The Aqua theme has also been embedded in applications made by Apple for use in Microsoft Windows such as iTunes, QuickTime, and the Safari web browser (although removed on Safari 4). iTunes for Windows has followed the same theme as the Mac OS X version, with the exception of the use of native Windows user interface controls and Windows-style titlebar buttons at the upper right of the player window.

The Windows version of Safari, in version 3, included a functional Aqua look and feel (including pulsing scrollbar, sheets, and other interface similarities). As of version 4, a more Windows-like theme is employed using the standard Windows user interface controls and window border.

QuickTime for Windows uses the same theme as seen in older versions of QuickTime for Mac OS X, with Brushed Metal windows and Aqua buttons on top.

User interface

White and blue are two principal colors which define the Aqua style. Title bars, window backgrounds, buttons, menus and other interface elements are all found in white, and some, like scrollbars and menu items, are accented with a shade of blue. Most of the interface elements have a "glass" or "gel" effect applied to them; for instance, David Pogue described the original Aqua scrollbars as "lickable globs of Crest Berrylicious Toothpaste Gel".

Mac OS X also allows users to choose a Graphite version instead of a Blue version of the interface. When using the Graphite scheme, controls appear grey rather than blue or multicolored. For example, the title bar controls become three grey balls rather than traffic lights. This color scheme was added at the behest of developers and users who found the blue scheme to be too garish or unprofessional.

Interface elements

Most of the controls are available in three sizes: regular, small and mini.

Windows

Both the standard Aqua-themed pinstriped windows and the brushed metal windows appear to have the title bar buttons sunken into the window, however in versions of Mac OS X prior to 10.2, the buttons appeared to be on top of the pinstriped windows. Brushed metal windows also have more plastic-like buttons.

Toolbars are available in two types: standard or unified. Standard retains the normal Aqua title bar and simply places a row of icons below it, whilst the unified look extends the title bar downwards and places icons on top of it, as if the window has one large title bar.

Sheets are dialog boxes that are modal to a specific window. When opened, they are thrust towards the user like a sheet of paper, hence the name. They are partially transparent and focus attention on the content of the sheet. The parent window's controls are disabled until the sheet is dismissed, but the user is able to continue work in other windows (including those in the same application) while the sheet is open.

Menus

The menu bar in Leopard.

Menus are backed with a slightly translucent solid gray, and when menu items are highlighted they appear blue. In application menus, which run in a single bar across the top of the screen, keyboard shortcuts appear to the right-hand side of the menu whilst the actual menu item is on the left.

Drop down menus for use in windows themselves are also available in several varieties. The standard "pop up" menu is white with a blue end cap with opposing arrows, whilst 'pull down' menus only have one downward facing arrow in the end cap. 'Pull down' menus are available in four different Aqua varieties, most of which have fallen into disuse in later Mac OS X releases.

Text boxes and fields

Text boxes are black on white text with a sunken effect border. In addition to regular square text boxes, rounded search text boxes are available . For more extensive text requirements, there is also a multi-line text field. A combined text box and pull down menu is available, which allows the user to type in a value in addition to choosing from a menu. There is also a combination textbox and picker control, which allows the user to type in a date and time or edit it with directional buttons. Mac OS X v10.4 introduced a new interface element that allows the user to drag non-editable 'tokens' to a text box, between which text can be typed. Whitespace before and after the tokens is trimmed.

Push buttons

Standard push buttons with rounded corners are available in two varieties: white and blue. A blue button is the default action, and will appear to "pulse" to prompt the user to carry out that action. The action of a blue button can usually also be invoked with the return key. White buttons are usually associated with all other actions.

Also available are rounded bevel buttons, designed to hold an icon; standard square buttons; glass square buttons and round buttons. In addition, circular, purple online help buttons are available which display help relative to the current task when clicked. Disclosure triangles, although technically buttons, allow views of controls to be shown and hidden to preserve space.

Checkboxes and radio buttons

In Mac OS X, empty check boxes are small, white rounded rectangles. When they are checked, they turn blue and a checkmark is present. They are essentially buttons which can be toggled on or off. Radio buttons are similar in appearance and behaviour except they are circular and contain a dot instead of a check. Radio button are classed into groups of which only one can be activated at a time.

Tables and lists

Tables and lists can be broadly categorised in three ways: A standard multi-columnar table with space to enter values or place other interface elements such as buttons; An outline view that can contain disclosure triangles to show and hide sets of data; and a Miller columns view akin to the column view in the Finder. All table views can use alternating blue and white row backgrounds.

Progress indicators

Two main types of loading/saving progress indicator are available: a progress bar or a monochromatic spinning wheel (not the spinning pinwheel). The progress bar itself is available in two varieties: indeterminate, which simply shows diagonal blue and white stripes in animation with no measure of progress; or determinate, which shows a blue pulsing bar against a white background proportional to the percentage of a task completed. The spinning wheel indicator, also found in the Mac OS X startup screen since version 10.2, is simply a series of 12 increasingly darker grey lines arranged circularly, like the side view of a spoked wheel rotating clockwise. Many other interfaces have adopted this device, including the Firefox and Camino web browsers and many Web 2.0-influenced web sites.

Miscellaneous

Sliders are available in three types: one with tick marks and a triangular scrubber, one with a round scrubber and no tick marks and a circular slider which can be rotated. All are available horizontally or vertically. The circular slider is simply a gray dot on a white circle which can be rotated to set values.

Mac OS X has a standard control for picking colors which appears as a regular square button with a color sample in the middle. When clicked, it shows the standard Mac OS X color palette.

Tab views in Mac OS X appear to be sunken into the window, and are shaded darker and darker each time a new tab view is added inside another. The tabs appear in a row along the top of the sunken area, and are simply a series of white toggle buttons. The currently selected tab is blue. There is a similar control used to group interface elements that uses the same sunken appearance, except without tabs. Image "wells" are also available: a small, sunken container into which image files can be dropped. When the well contains an image, it can display a thumbnail representation of the file's contents.

Fonts

Apple uses the Lucida Grande font as the standard system font in various sizes and weights. Some areas of the operating system such as editable text areas use another font, Helvetica by default. Mac OS X makes use of system-wide font anti-aliasing to make edges appear smoother.

Animation

A widget being added to the Dashboard in Mac OS X 10.4. Shown here is the ripple effect.

Aqua makes heavy use of animation. Examples include:

• Dock icons bounce up and down as their corresponding applications are launched.
• Dock icons also bounce up and down, in a different rhythm, when a background application requires the user's attention.
• Dock icons can increase in size when approached by the cursor. This feature (called "magnification") is optional.
• When minimized, windows are "sucked" into the Dock using the "Genie effect" or "Scale effect." Both of the effects are customizable by the user. The former makes a window turn into a curvy shape so it looks like reverse animation of a genie exiting a lamp, and the latter scales down the window until it is small enough to be in the dock. Using the shift key, both effects can be seen in slow motion. These keystrokes can also be applied to other Aqua effects such as Dashboard, Exposé and Front Row. Holding control as well as shift makes the minimize effect take twice as long as just holding shift. Holding just control also slows down the animation slightly. There is another undocumented dock effect called "Suck" which can be enabled by hand editing a configuration file.; this, appears to be the same effect that accompanies removing widgets from the Dashboard.
• When a folder on the desktop is opened or closed, the corresponding Finder window appears to come from, or disappears into, the folder icon rather than just appearing from nowhere.
• Sheets are "posted" out of window title bars. Sheets appear to be pieces of paper being thrust toward the user, or slide out like paper from a tray.
• Dashboard widgets appear to fly onto the screen. Dashboard widgets appear with a "ripple" effect, as if being dropped onto the surface of a pond. When removed, Widgets are sucked into the close button as if being drawn into a vacuum. This effect can be applied on windows being minimized to the Dock. Starting from Mac OS X 10.7 Lion, the default Dashboard configuration differs from that of previous versions (it takes its own space in Mission Control), causing the rippling effect to be removed. However, the user can re-invoke the original Dashboard (along with the ripple effect) in System Preferences.
• The contents of a stack will appear to spring out from behind the icon when clicked.
• In the Public Beta of Mac OS X, docked items dragged on to the desktop simply disappeared, apparently 'dropping' onto the desktop. This behaviour was changed with Mac OS X 10.0; from this release onward items dragged off the dock would 'disappear' in a cartoon-like puff of smoke, an effect which is used in various places in the system (such as Safari's Bookmarks Bar and iPhoto's tag removal). A similar effect was used in Apple's Newton OS.
• Starting from Mac OS X 10.7 Lion, windows which contain a document or website, open with an animation similar to Windows Aero. A similar zoom effect can be seen when opening files from the desktop, or within a Finder window. This also applies to the entire desktop when a user logs in.
• When fast user switching is used, Apple's "Cube" effect is used to transfer between desktops and/or the login window.

Many of these effects can be turned off by the user or are only available on supporting hardware.

Underlying technology

Aqua is powered by the Quartz Compositor, the Mac OS X window server.

Litigation

Apple has threatened legal action against those who made themes similar to their look and feel.

Despite accepting (for the most part) Apple's right to their copyrighted artwork, the skinning community took exception to their heavy-handed actions against all Aqua lookalikes; Stardock's Brad Wardell contrasted the company's litigious approach with Microsoft's approach to incorporating third-party skins into Windows XP.

See also

• Windows Aero
• Compiz
• KWin
• Metro Design Language

External links

• Apple Mac OS X Aqua Human Interface Guidelines