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Item Representation

The visible portion of an item's knowledge is called its representation. An item's representation is determined by the representation style of its class, for example, its icon, text box, workspace, table, chart, and so on. The next two figures, Samples of G2's Item Representation Styles, Part I and Samples of G2's Item Representation Styles, Part IIshow several representation styles for G2 items.

Note: The representation of an item (other than connections) always occupies a rectangular region on the screen, even if the visible portion of the representation is not rectangular.

Samples of G2's Item Representation Styles, Part I

Samples of G2's Item Representation Styles, Part II

Identifying the G2 Color Palette

G2 supports a large set of colors. G2 displays its color palette when you select color on the menus of items. You can assign any supported color to any color attribute of an item, or to any region of the icon of a system-defined or user-defined class.

The G2 color palette provides these colors:

antique white
aquamarine
azure

beige
black
blue

brown
cadet blue
coral

cyan
dark gray
dark slate blue

dim gray
extra light gray
floral white

forest green
gold
goldenrod

gray
green
green yellow

indian red
ivory
khaki

lavender
light blue
light cyan

light goldenrod
light goldenrod yellow
light gray

light pink
light steel blue
light yellow

lime green
linen
magenta

maroon
medium aquamarine
medium blue

medium goldenrod
medium orchid
orange

pale goldenrod
pale green
pale turquoise

pink
plum
powder blue

purple
red
salmon

sienna
sky blue
slate blue

smoke
tan
thistle

turquoise
violet
violet red

wheat
white
yellow

The G2 color palette also includes the metacolors foreground, background, and transparent. Each metacolor assigns a color value for an item's color attribute by referring to a color attribute of another item:

A metacolor of foreground means that the actual color is determined by the color value of the foreground color attribute of the item's parent workspace.
A metacolor of background means that the actual color is determined by the color value of the background color attribute of the item's parent workspace.
The metacolor transparent means exactly that: whatever you assign to this metacolor becomes transparent. Any item beneath a transparent item or icon becomes visible.
You can select and drag a transparent item. Any visible knowledge that is behind the transparent item, or other entity with color, is visible.
You cannot set the background-color color attribute of a workspace to transparent.

Identifying the Color Attributes of Items

Each representation style has a corresponding set of color attributes. A color attribute is a component of an item's representation that can appear in a distinct color.

Each item representation presents a set of color attributes:

The icon representation has the icon-color color attribute.
The text box representation has the text-color, border-color, and background-color color attributes.
The workspace representation has the foreground-color and background-color color attributes.
The connection representation has the stripe-color color attribute.

Other item representations do not have settable color attributes.

Note: The icon-color color attribute of an item is distinct from the color regions defined for its icon. For more information about icon color regions, see Composition of an Icon.

The settings of an item's color attributes are part of its knowledge. You can set the color attributes of items interactively or programmatically.

To set a color region of an item interactively:

Select the color choice on the item's menu as described in

Changing the Color of an Item

Actions That Affect Item Appearance

G2 provides the following actions that change an item color or pattern:

To change a color attribute of an item:

change the color-attribute-name of item to {color-name | symbolic-expression}

To change a color pattern of an item:

change the color-pattern of item so that
{color-attribute-name is color-name} [, ...]

For items with an iconic representation, you can programmatically set the icon-color region as well as any other user-defined icon color-region.

To change an icon region of an item:

change the region-name icon-color of item to color-name

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