Service objects: Representation

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Domain Representation Georeference Coordinate system
Representation

A Representation contains information used by a domain to defines the manner in which classes of a map or the values of a map should be represented on a monitor and a printer. A representation stores colors or ranges of colors for the classes in items domain, or for specific values or ranges of values for the values domain.
There are three types of representations:

  • Representation class; used for classes in a items domain coverage. For each class in the domain, a representation class contains: colors information for mapping units in raster maps; colors, hatching or patterns for polygons; colors, line types, line widths for segments; colors, symbol type and sizes for points.
  • Representation gradual; defines colors for ranges of values (as percentages) in any value map. Any map with a value domain can be displayed with any existing representation gradual. Examples of representations of type gradual are Gray and Pseudo.
  • Representation value; defines colors for ranges of values in a value map when the map uses a user-defined value domain (e.g. a Height domain), or a system value domain.

The following system representations are representations gradual:

Representation names Description
Blue From black to blue in 16 stretch steps.
Clrstp6 Six times from black to a color (6 colors between blue to red), each time in 8 stretch steps.
Clrstp8 Eight times from black to a color (8 colors between blue to red), each time in 8 stretch steps.
Clrstp10 Ten times from black to a color (10 colors between blue to red), each time in 8 stretch steps.
Clrstp12 Twelve times from black to a color (12 colors between blue to red), each time in 8 stretch steps.
Cyan From black to cyan in 16 stretch steps.
FineGray From black to white in 60 stretch steps.
Gray From black to white in 30 stretch steps. it is used by system domain such as Byte, Count, Min1to1 and Perc.
Green From black to green in 16 stretch steps.
Inverse From white to black in 30 stretch steps.
Magenta From black to magenta in 16 stretch steps.
Pseudo From blue to green to red in 6 x 9 stretch steps. Default representation for system domain Value and system domain Distance.
Red From black to red in 16 stretch steps.
Yellow From black to yellow in 16 stretch steps.

The following is item system representation for system domain NILto1:

Representation names Description
NILto1 Designed for SMCE standardized maps that have values between 0.00 and 1.00:
  • from red (0.00) to yellow (0.50) in 10 stretch steps, and
  • from yellow (0.50) to green (1.00) in 10 stretch steps.

Default representation for system domain NILto1.

The following system representations are used by system domains ColorCmp and FlowDirection:

Representation names Description
ColorCmp Designed for output raster maps of the Color Composite operation created with the Standard option; 216 colors.
FlowDirection Designed to display the eight compass directions N, NE, E, SE, S, SW, W, NW, W; default representation for maps using system domain FlowDirection.

Output maps of the Flow Direction operation always use FlowDirection system domain and representation.

Note that system representations cannot be edited, but users can always create a new representation by using the workbench button Create.