PlanarityFilter

Categories

3D

Data Quality

Filters and Joins

Related Transformers

FaceReplacer

Filters features based on their planarity. To be planar, a geometry must have all its points situated in the same plane.

This transformer works only on the following geometries:

  • points
  • curves
  • areas (polygons, ellipses, and donuts)
  • multi-areas
  • surfaces
  • multi-surfaces
  • composite surfaces

Configuration

Input Ports

Typically area-based or surface-based geometries.

Output

If an area-based or surface-based geometry has all of its points situated in the same plane, its features are sent to the Planar output port.

If an area-based or surface-based geometry is not planar, its features are written to the NotPlanar output port.

All features with geometry types other than points, curves, multi-curves, areas, multi-areas, surfaces, multi-surfaces, or composite surfaces will be sent to the <REJECTED> output port.

Parameters

Thickness Mode

Select an option or choose an attribute. Automatic estimates a valid thickness for the geometry. Custom allows you to input your own thickness. Ignore ignores the thickness check entirely.

Thickness

Enter a value or choose an attribute. The thickness tolerance is specified in ground units, and describes the maximum “thickness” a plane can have before it is considered non-planar. A planar polygon has a thickness of 0. A non-planar polygon will have its average surface normal computed using Newell’s method, and its thickness will be determined in the direction of the normalized surface normal.

For example, consider a single, non-planar polygon. Imagine a plane that passes through the world origin, with its normal set to the average normal of the polygon. Then, every point along the polygon boundary would be a distance D to the world plane. Relative to the world plane, we find the closest point and the farthest point along the polygon boundary. The difference between the farthest and nearest distances give us the desired thickness.

Angular Mode

Select an option or choose an attribute. Automatic estimates a valid surface normal deviation for the geometry. Custom allows you to input your own surface normal deviation (in degrees). Ignore ignores the surface normal check entirely.

Surface Normal Deviation (degrees)

Enter a value or choose an attribute. The surface normal deviation tolerance is specified in degrees, and describes the maximum deviation from the average surface normal that a component can have before it is considered non-planar. A planar polygon has a surface normal deviation of 0. A non-planar polygon will have its average surface normal computed using Newell’s method, and the surface normal deviation of each part from the average surface normal will be computed with the cosine law.

For example, consider a single, non-planar polygon. Imagine a unit normal representing the average normal of the polygon. Now imagine a unit normal for each component of the polygon. The largest different between the average surface normal, and any other surface normal is the surface normal deviation.

If Specify Plane Normal is left unchecked, the average surface normal is determined using Newell’s method. In the case of surfaces with multiple components, such as MultiSurfaces or CompositeSurfaces, the average surface normal is determined from the first component. The effect is that coordinates must lie in the same plane, but that may be any plane.

If Specify Plane Normal is checked, then all coordinates must lie in a plane with the normal vector given by the Normal X, Y, and Z parameters. If the geometry contains multiple components, such as multi-surfaces, multi-areas, donuts, or composite surfaces, then each component must be coplanar with all of the other components, and must be within tolerance of the specified plane normal.

Normal X, Y, Z

Sets the x, y, and z components of the vector normal specifying the plane against which to test.

Expose Surface Normal

If set to Yes, the Planar and NotPlanar outputs will have up to 6 extra attributes relating to the surface normal. If a non-degenerate surface normal was found, _surfaceNormalX, _surfaceNormalY, and _surfaceNormalZ indicate the vector that was used to perform the planarity check. _pointOnSurfaceX, _pointOnSurfaceY, and_pointOnSurfaceZ indicate a point on the surface. Together these entries can be used to define a vector that originates on the surface, and is collinear to the surface normal used to perform the planarity check.

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.

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.

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.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.

Row Reordering

Enabled once you have clicked on a row item. Choices include:

  • Add a row
  • Remove a row
  • Move current row up one
  • Move current row down one
  • Move current row to top
  • Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

  • Cut a row - delete and copy to clipboard
  • Copy a row to the clipboard
  • Paste a row from the clipboard

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.

FME Community

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Keywords: planar planarity "flat plan"