ComGraphix Data Exchange Format (CGDEF) Feature Representation

In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Type Attributes), this format also adds format-specific attributes (Format Attributes).

CGDEF features consist of geometry but no user-defined attributes, although there are special attributes to hold the type of the geometric entity and its display parameters.

FME considers the CGDEF overlay name to be the FME feature type of a CGDEF feature. When writing, the CGDEF writer will create a new overlay for each unique feature type that is passed to the writer. All CGDEF features contain a cgdef_type attribute, which identifies the geometric type. Each geometric/element type can also have an id, up to 31 characters long, associated with it. Every element type except symbols will have associated colors attached to it. Both cgdef_symbol_name and cgdef_symbol_sequence_number are fields that are only filled if the element is part of a symbol instance. Depending on the geometric type, the feature contains additional attributes specific to the geometric type. These are described in subsequent sections.

Attribute Name

Contents

cgdef_type

The CGDEF geometric type of this entity.

Range:

cgdef_symbol

cgdef_polyline

cgdef_polygon

cgdef_text

cgdef_ellipse

cgdef_arc

Default: No default

cgdef_element_id

The CGDEF ID for this entity, this is an optional attribute

Range: String

Default: No default

cgdef_color.red

The element’s red color intensity, as determined by looking up the element’s color index in the color table.

Range: 0..65535

Default: 27000 (when writing only)

cgdef_color.green

The element’s green color intensity, as determined by looking up the element’s color index in the color table.

Range: 0..65535

Default: 30000 (when writing only)

cgdef_color.blue

The element’s blue color intensity, as determined by looking up the element’s color index in the color table.

Range: 0..65535

Default: 38000 (when writing only)

fme_color

This is a string that represents the color intensities of the element. It is formatted as red, green, blue intensities which range between 0..1 This 0..1 value is arrived at by taking the color intensity and dividing it by the total intensity range, in this case, 65535

Range: String. (0..1, 0..1, 0..1)

Default: 27000/65535, 30000/65535, 38000/65535(when writing only)

cgdef_symbol_name

If the element is part of a symbol and the symbol has been exploded into its individual elements, then this field contains the symbol name

Range: String

Default: None

cgdef_symbol_
sequence_number

If the element is part of a symbol and the symbol has been exploded into its individual elements, then this field contains the a unique number which identifies itself and the other elements in the symbol

Range: String

Default: None

Symbols

Symbol and Group Definitions

Text

Polylines

Ellipse

Arc