🝖 Edge Direction (Edge)

PCGEx | Cluster Filter : Edge Direction (Edge)

Check if the edge direction is within a given range.

The Edge Direction filter compares the direction of of the edge using a dot product.

Edge Filter

A single cluster filter definition

Table of content

Properties
- Direction Settings
- Comparison Quality
  - Dot Comparison Details
  - Hash Comparison Details

WIP

details/cluster-filters/filter-edge-edge-direction-lead.png

Properties

Property	Description
Settings (Operand A)
Direction Settings	Used to determine which edge endpoint is either the start or end. See below.
Comparison Quality	Defines the method used for comparison. - `Dot` is precise (easily returns false) - `Hash` method is approximative (easily returns true)

Operand B
Compare Against	Type of operand B. Can be a per-edge point `Attribute`, or an easily overridable `Constant`.
Direction `FVector`	Attribute to read the direction vector to compare the edge direction against.
Direction Constant	Constant direction vector to compare the edge direction against.
Transform Direction	If enabled, the direction to compare will be adjusted by the current edge point’ transform. If disabled, the direction is in world space.

Direction Settings

Property	Description
Direction Method	Defines which endpoints “order” will be used to define the direction reference for the ouputs.
Direction Choice	Further refines the direction method, based on the above selection. -`Smallest to Greatest` will order direction reference metrics in ascending order. -`Greatest to Smallest` will order direction reference metrics in descending order. Really it’s how the endpoint reference value is sorted, but I couldn’t call that Direction’ direction.
Dir Source Attribute	The attribute that will be used by the selected method.

If the selected method is Edge Dot Attribute, the attribute will be read from Edges as an FVector direction.

Method

The Direction method, combined with the Direction Choice determine which endpoint should be considered the Start & End of the edge. The “direction” of the edge used for computing outputs & properties is the safe normal going from the start to the end of the edge.

Mode	Description
Endpoints order	Will use the endpoints’ as ordered during cluster construction.
Endpoints indices	Will use the endpoints’ point index.
Endpoints Sort	Enables the use of any number of Sorting Rules to determine direction. This method, while more expensive, is the most efficient.
Edge Dot Attribute	Will use an attribute (converted to an `FVector`) from the edges’ and do a Dot Product with the edge’ direction. This method, combined with `Direction Choice` offers full control over direction.

Comparison Quality

details/settings/comparison-quality.png

Dot Comparison Details

Only if Dot method is selected

Property	Description
Comparison	Which comparison to use. See Numeric comparisons.
Dot Units	Let you choose to work either with normalized dot range (`-1 / 1`) or degrees. This affects how the attribute Dot value will be interpreted as well.
Unsigned Dot	When enabled, the comparison will occur against an absolute dot value. This is especially useful when testing against undirected lines.
Dot Value	The type of value used for this probe’ search radius; either a `Constant` value or fetched from an`Attribute`
(Dot or Degrees) Constant	Constant to compare against.
(Dot or Degrees) Attribute	Constant to compare against.
(Dot or Degrees) Tolerance	Comparison tolerance, if the selected comparison is an approximative (`~`) one.

Hash Comparison Details

Only if Hash method is selected

Property	Description
Hash Tolerance Value	Where to read the tolerance from. Can be a per-point `Attribute`, or an easily overridable `Constant`.
Hash Tolerance Attribute	Attribute to read tolerance from.
Hash Tolerance Constant	Constant hash tolerance value.