How to use representations

Representation types

Representations can be created and selected depending on the domain of the map.

For maps with a class domain or group domain, you have to create and edit a user-defined representation Class (1).

For maps with a value domain or the image domain, two types of representations are available: representation Value (2) and representation Gradual (3).

Maps with a domain ID can only be displayed in 1, 7, 15, or 31 system colors.

1. Representation Class:

A representation Class is user-defined: colors have to specified for all classes in a certain class domain, see Representation Class editor. Each class is represented by a specific color. You can create multiple representations for the same domain.

2. Representation Value:

A representation Value is user-defined: colors can be specified for different values in a certain Value domain, see Representation Value/Gradual editor. You can specify the colors for the smallest and largest values in the domain and insert other breakpoints/limits as required.

Each value is represented by a specific color. You can create multiple representations for the same domain.

3. Representation Gradual:

A number of system representations Gradual are available:

Gray: from black to white (default for images).
Inverse: from white to black.
Pseudo: from blue via green to red.
Red, Green, Blue, Yellow, Magenta, Cyan: from black to pure color.
ClrStp6, ClrStp8, ClrStp10, ClrStp12: 6, 8, 10, 12 times from black to a pure color; pure colors ranging from blue to magenta. Useful for DEMs, distance maps, etc.

A representation Gradual can also be user-defined. The domain of a representation Gradual is the system domain Value. Each value in the map is stretched to a percentage value between 0 and 100; each percentage value is represented by a specific color, see Representation Value/Gradual editor. You can specify the colors for 0% and 100% and insert other breakpoints/limits as required. Representations Gradual can be used for all maps with a value domain.

Domain and representation

All maps with the same domain are displayed with the same representation. Every domain is always linked to one representation.

To view which representation is currently used by a certain domain, or to select or to create a new representation, open the Display Options dialog box or the Domain Properties dialog box.

To obtain a Display Options dialog box:

in the Catalog, double-click a map, or
from the File menu in the Main window, choose Open, and select a map, or
in a map window, open the Layers menu, choose the Display Options command, and select the layer, or
in a map window, open the Layers menu, choose the Layer Management command, select the layer and click the Display Options button, or
in a map window, use the right mouse button, and select a layer from the context-sensitive menu.

To obtain a Domain Properties dialog box:

from the Edit menu of the Main window, choose Change Properties and select a domain Class, Group or Value, or
select a domain Class, Group or Value in the Catalog, use the right mouse button, and select Properties from the context-sensitive menu, or
in a domain Class editor, open the Edit menu, and choose the Properties command.

Using representations

To create a new representation for a domain Class, Group, Value or Image:

in a Display Options dialog box of a domain Class, Group or Value map or an Image, click the little create button next to the representation list box, or
in a Domain Properties dialog box, create a new representation through the little create button, or
from the File menu of the Main window, choose Create Representation, or
in the Operation-list, double-click icon New Repr.

To link another representation to a domain:

in a Display Options dialog box of a domain Class, Group, Value map, or Image select another representation, or
in a Domain Properties dialog box, select another representation.

To edit an existing representation:

when a map with a domain Class, Group, Value or Image is displayed in a map window, open the Edit menu in the map window, choose Representation, or
when a map with a domain Class, Group, Value or Image is displayed in a map window, set the double-click action in the map window to Edit Representation, and double-click a unit in a domain class map, or
in the Catalog, double-click a user-defined representation, or
in the Catalog, double-click a domain Class, Group, or Value, then choose Representation from the Edit menu, or
in the domain Class/ID editor, open the Edit menu and choose the Representation command.

For more information on Representation editors, see How to edit a representation.