OffsetCurveGenerator

In this example, we will create offset lines on either side of a rapid transit line. The original feature is a single line.

The line is routed into the Lines input port.

In the parameters dialog, we set the Offset to 100, which will create the new offset lines 100 meters away from the original feature (which is in a UTM projection, ground units in meters). The Corner Style chosen is Round.

Two new lines are output from the transformer - one on the left side of the original line (shown in green), and one on the right (shown in red).

In a scenario where only one side is needed (left or right), simply disregard the unneeded output port.

Offset curves will be built in 2D from linear features. Self intersecting lines are not supported, and may produce unpredictable results. Other types of geometry will be output through the <Rejected> port.

Each point in the output curve will be the specified offset, measured in ground units, away from the input linear geometry. The output ports Left and Right will produce offset curves on either side of the linear geometry.

Features without line geometry are output through this port along with an additional attribute, fme_rejection_code, to indicate the reason for rejection.

Rejected Feature Handling: can be set to either terminate the translation or continue running when it encounters a rejected feature. This setting is available both as a default FME option and as a workspace parameter.

Using the Text Editor

The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.

Text Editor

Using the Arithmetic Editor

The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.

Arithmetic Editor

Conditional Values

Set values depending on one or more test conditions that either pass or fail.

Parameter Condition Definition Dialog

Content

Expressions and strings can include a number of functions, characters, parameters, and more.

When setting values - whether entered directly in a parameter or constructed using one of the editors - strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.

Content Types

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	FME and workspace-specific parameters may be used.
Creating and Modifying User Parameters	Create your own editable parameters.

Note: Not all tools are available in all transformers.