CenterPointExtractor
Extracts and outputs the specified x, y, and z attributes of a feature's point that is either in the center of the feature's bounding box, at the center of mass of the feature, or somewhere guaranteed to be inside the feature's area.
Output Port
This port outputs the result of the extracted point in the specified x, y, and z attributes.
This port outputs null geometry features, and when Point Extraction Mode is Any Inside Point, all non-area geometry features.
Note: Feature order may change in relation to other output ports. Feature order per port is maintained.
Parameters
Center of Bounding Box: Extracts the point that is in the center of the feature's bounding box into the specified x, y, and z attributes. Depending on the feature’s shape, the resulting point may be far outside of the original feature.
Center of Gravity: Extracts the point at the feature's center of mass into the specified x, y, and z attributes. Depending on the feature’s shape, the resulting point may be far outside of the original feature.
Any Inside Point: Extracts a point that is guaranteed to be inside the feature's area into the specified x, y, and z attributes.
Example
The following illustration shows the result when the Point Extraction Mode is Center of Gravity. The transformer calculates the exact distribution of portions of a shape; therefore, some points can actually appear outside a feature.
Usage Notes
If the Point Extraction Mode is Center of Bounding Box or Center of Gravity, depending on the feature's shape, the resulting point may be far outside of the original feature.
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.
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.
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.
Row Reordering
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Enabled once you have clicked on a row item. Choices include:
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Cut, Copy, and Paste
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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
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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
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Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers. |
Reset/Refresh
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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.
FME Community
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Search for samples and information about this transformer on the FME Community.
Keywords: MBR "minimum bounding rectangle" CenterPointCreator CentrePointCreator CentrePointReplacer