Replaces or creates feature geometry with a 2D ellipse as defined in parameters for center point, radii, and rotation.
Typical Uses
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Creating ellipse or circle geometry from attribute values or user parameters
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Replacing point geometry with ellipses or circles defined by values
How does it work?
The 2DEllipseReplacer receives features of any kind and replaces their geometry with ellipses as defined in parameters.
The parameters describe an ellipse as a closed Arc By Center Point by the following:
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Center X and Y coordinates
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Primary and Secondary Axis (radii) in ground units
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Rotation in degrees
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An assumed sweep of 360 degrees
Values may be entered or provided through attribute values, expressions, or user parameters.
If the feature has point or ellipse geometry, and Center X and Y are left blank, the coordinates of the feature’s existing geometry will be used. If the feature has no geometry or geometry other than point or ellipse, the feature is rejected.
For more information on ellipse geometry see Ellipse.
Examples
Example: Replacing points with ellipses
In this example, we have a set of points and want to replace them with ellipses of a fixed size and orientation.
The features are routed into a 2DEllipseReplacer.
In the parameters dialog, values are entered for Primary and Secondary Axis and Rotation, but the Center X and Y parameters are left blank.
The points have been replaced by ellipses as specified.
Usage Notes
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To create circles around point features, consider using a Bufferer.
Creating and Modifying Arcs, Circles, and Ellipses
These transformers work with arcs in a variety of ways.
Arc Transformers Comparison
|
|
Function |
Geometry Out |
Z Coordinates |
|---|---|---|---|
|
Creates one or more new features with arc geometry (when Geometry Object is an arc type). |
Arc by center point Arc by center point with ends Arc by 3 points Arc by bulge Ellipse (Arc by center point) |
Supported |
|
|
Replaces any existing feature’s geometry with a 2D arc. |
Arc by center point |
No |
|
|
Replaces any existing feature’s geometry with a 3D arc. |
Arc by center point |
Yes, at center point |
|
|
Replaces an existing feature’s geometry with a 2D ellipse or circle (closed arc). |
Ellipse (Arc by center point) |
No |
|
|
Modifies an existing arc or converts a point to an arc. |
Arc by center point Arc by center point with ends Arc by 3 points |
Supported, at center and/or ends |
|
|
Modifies an existing ellipse (closed arc) or converts a point to an ellipse. |
Ellipse (Arc by center point) |
Supported, at center point |
|
|
Extracts the property values that describe an arc’s geometry and stores them as attributes. |
Arc by center point Arc by center point with ends Arc by 3 points Arc by bulge |
Supported |
|
|
Extracts the property values that describe an ellipse’s geometry and stores them as attributes. |
Ellipse (Arc by center point) |
Supported |
|
|
Converts arcs and ellipses to lines or polygons by interpolating points along the arc. |
Path Line Area |
Supported |
|
|
Replaces geometry with an arc described by the first, middle, and last vertices of the input feature. |
Arc by 3 points |
Supported |
|
|
Replaces lines or polygons with an optimal combination of line and arc segments, creating smooth curving lines. |
Path Area Arc by bulge Line |
Supported |
|
|
Reduces point density on lines or polygons, fitting arcs where possible (When using Algorithm > Douglas With Arc Fitting (Generalize) ). |
Path Area Arc by 3 points Line |
Supported |
|
|
Either replaces an existing feature’s geometry with circle that contains all of its vertices or extracts the circle property values into attributes. |
Ellipse (Arc by center point) |
No |
Configuration
Input Ports
Input
This transformer accepts any feature.
Output Ports
<Rejected>
If only one of Center X and Center Y is specified, then all features are output through the <Rejected> port.
If Center X and Center Y are blank, features with non-ellipse/point geometries are output here.
Features that receive non-numeric values for any numeric parameters are output via this port.
Rejected features will have an fme_rejection_code attribute with one of the following values:
INVALID_PARAMETER_PRIMARY_RADIUS
INVALID_PARAMETER_SECONDARY_RADIUS
INVALID_PARAMETER_ROTATION
INVALID_PARAMETER_CENTER_POINT
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.
Parameters
General
|
Center X |
Specify the X coordinate of the ellipse’s origin. If blank, and the input feature is a point or ellipse, the X coordinate of that feature’s geometry will be used. If blank, and the input feature is not a point or ellipse, the feature is output via the <Rejected> port. |
|
Center Y |
Specify the Y coordinate of the ellipse’s origin. If blank, and the input feature is a point or ellipse, the Y coordinate of that feature’s geometry will be used. If blank, and the input feature is not a point or ellipse, the feature is output via the <Rejected> port. |
|
Primary Axis |
Specify the primary radius of the ellipse in ground units. Note that the primary radius need not be larger than the secondary, however, the rotation angle is always measured from the x axis to the primary axis. For a circle, set both the primary and secondary radius to the same value. |
|
Secondary Axis |
Specify the secondary radius of the ellipse in ground units. |
|
Rotation |
Specify the rotation in degrees of the primary axis from horizontal (if any). |
Editing Transformer Parameters
Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click 
beside the applicable parameter. For more information, see Transformer Parameter Menu Options.
Defining Values
There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.
How to Set Parameter Values
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.
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.
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
| These functions manipulate and format strings. | |
|
Special Characters |
A set of control characters is available in the Text Editor. |
| Math functions are available in both editors. | |
| Date/Time Functions | Date and time functions are available in the Text Editor. |
| These operators are available in the Arithmetic Editor. | |
| These return primarily feature-specific values. | |
| FME and workspace-specific parameters may be used. | |
| Creating and Modifying User Parameters | Create your own editable parameters. |
Dialog Options - Tables
Transformers with table-style parameters have additional tools for populating and manipulating values.
Table Tools
|
Row Reordering
|
Enabled once you have clicked on a row item. Choices include:
|
|
Cut, Copy, and Paste
|
Enabled once you have clicked on a row item. Choices include:
Cut, copy, and paste may be used within a transformer, or between transformers. |
|
Filter
|
Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer - it does not alter which attributes are output. |
|
Import
|
Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers. |
|
Reset/Refresh
|
Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers. |
Note: Not all tools are available in all transformers.
Reference
|
Processing Behavior |
|
|
Feature Holding |
No |
| Dependencies | None |
| Aliases | |
| History |
FME Community
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Search for all results about the 2DEllipseReplacer on the FME Community.
Examples may contain information licensed under the Open Government Licence – Vancouver and/or the Open Government Licence – Canada.