Feature Representation

In addition to the generic FME feature attributes that FME Workbench adds to all features (see the chapterAbout Feature Attributes), this format adds the format-specific attributes described in this section.

All Generate features contain a numeric ID field. The numeric ID is stored in thearcgen_idattribute of an FME feature read from a Generate file or destined to be written to a Generate file.

Tip:Features being written to anARCGENfilemusthave anarcgen_id attribute.

FME considers the basename of the Generate file to be the FME feature type of a Generate feature. The feature type of a Generate feature must match the basename of a Generate file defined by a Generate DEF line. Each feature read from a Generate file has an ARCGEN_GEOMETRY attribute added to it that indicates if the feature came from an arcgen_point, arcgen_line, or arcgen_text file. The writer can also handle homogeneous aggregate features of points, lines or text, which also have an ARCGEN_GEOMETRY attribute.

Points

Generate files containing only points consist of a series of lines that follow this syntax:

,,[,]

Tip:By using theidNumberassociated with each Generate feature as a key into a comma-separated value file, the@Relatecommand can be used to attach attributes to Generate features.

Theis any numeric value, and need not be unique within a file. As well, thevalue is optional and, if it is not specified, the point is considered to be two-dimensional. The file is terminated by a line containing only the wordEND.

A two-dimensional point Generate file example is shown below:

601,3,7 602,53,21 603,19,20 END

Lines

Generate files containing only linear features consist of a series of lines that follow this syntax:

 ,[,] ,[,] … ,[,] END

Tip:Polygonal features may also be input and output using linear Generate files. In such cases, the first point and the last point of thelineare identical.

点文件,is any numeric value, and need not be unique within a file. As well, thevalue is optional and, if it is not specified, the linear feature is considered to be two-dimensional. The end of each linear feature is marked by a line containing only the wordEND. A linear Generate file is terminated with two consecutive lines containing only the wordEND. A three-dimensional linear Generate file example, containing two features, is shown below:

101 32,52,1 33,56,2 36,59,6 31,70,3 END 102 52,32,3 53,56,5 56,29,1 61,73,14 END END

Text

Generate files containing only text (annotation) features, consist of a series of lines that follow this syntax:

,,,,,

点文件,is any numeric value and need not be unique within a file. A Text generate file is terminated with the wordEND. A text Generate file example, containing two features, is shown below:

101,32,52,0,20,Arnet Maves 102,52,32,90,30,Barnie Maves END

The attributes used by the generate reader and writer are described in the following table.

Attribute Name	Value
arcgen_rotation	Specifies the rotation of the text in degrees measured counterclockwise from horizontal. Range: -360.0 . . . 360.0 Reprojectable: Yes
arcgen_text_size	The size of the annotation in ground units. Range: Float > 0 Reprojectable: Yes
arcgen_text_string	The text string to be placed at the annotation location. Range: Any text string

The example below shows an FME mapping file used to translate some points and linear features from the Generate format into Shape files. The mapping file defines the dataset location and gives the Generate definitions for the two files to be read. At run time, the Generate reader goes out to the folder, reads the files, and produces an FME feature for each Generate feature it finds.