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Extensible and Graphical Components

The G2 environment is both graphical and extensible. Almost everything in G2 has a graphical representation. You can use system-defined display items to show the state of your application as it changes over time, and system-defined buttons to send commands to G2 or the outside world. You can extend G2's graphics in various ways to provide a customized visual environment.


The preceding figure shows some system-defined and user-defined display items. G2 provides and allows you to customize many such items, including:

You can use system procedures to get information about, and then change, many graphical aspects of items, as described under System Procedures.

Buttons are described in Chapter 27, Buttons, readout tables, dials and meters in Chapter 32, Readout Tables, Dials, and Meters, and trend charts in Chapter 35, Trend Charts.

Icons, Images, and Fonts

All G2 items are represented graphically or textually. The iconic representation of items and objects supports a full range of colors. G2's Paint drawing mode permits polychrome icons to overlap and maintain their color. G2 includes a large palette of system-defined colors that you can apply to various KB items, including workspaces, icons, and textual items. Some examples of system-defined icons are:


G2 supports the use of X Bit Map (XBM) and Graphics Interchange Format (GIF) images within a KB. The G2 Icon Editor, which you can use to create new icons or edit existing ones, allows you to use images as icon components, where they appear in monochrome.

You can also use images to provide full-color workspace backgrounds. The following workspace has a color background image:


Textual items, such as messages and free text, use an outline font technology, making fonts more readable at smaller scales, and providing enhanced typographical detail for larger font sizes.

For information on creating and modifying icons, see Chapter 37, The Icon Editor and Icon Management. For information on importing and using externally defined images, see Chapter 30, External Images.

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