Properties : Edge

PCGEx | Cluster : Edge Properties

Compute edge extra data from its vertices

The Edge Properties node allows you to compute and write additional cluster-related data for edges, as well as “solidify” their bounds, giving them a more defined shape. The direction of the edge, from start to end, is determined by the chosen direction method and is used to influence outputs.

Vtx

Endpoints of the input Edges

Edges

Edges associated with the input Vtxs

Vtx

Endpoints of the output Edges

Edges

Edges associated with the output Vtxs

Working with Clusters

The Edge Properties node lets you extract & write cluster-related properties to individual Edges points, as well as “solidify” the edge points (i.e giving their bounds an decent shape).

details/clusters-edge-properties/lead.png

Properties

Direction

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.

explainers/edge-direction-method.png

Outputs

Property	Description
Outputs
Edge Length `double`
Edge Direction `FVector`
Endpoints Blending
Endpoints Weights
Blending Settings	Defines how each enpoint’ property (`Start` and `End` Vtx) is blended into the edge. See Blending.
Heuristics	If enabled, will reveal a new Heuristic input. This is used to ouput & debug the heuristic score of each edge. Note that heuristics that require external parameters won’t work correctly and output a constant value.

Note on blending: this is a 2-point blend, hence Lerp yields more accurate results than Weight.

Solidfication

Solidifying an edge means computing its bounds so they visually connect the start & end point.
This makes edge point incredibly more useful than just “data holders”!

Solidification is fairly straightforward on paper, but in order to be flexible it also exposes an overwhelming amount of parameters.

Unreal has a visual bug in the detail panel: the first time you select a solidification axis, remaining axis’ properties will not show up. *You have to deselect the node then select it again for the details panel to properly refresh.

Property	Description
Settings
Write Edge Position
Edge Position Lerp
Solidification Axis
Soldification Lerp Operand
Soldification Lerp (Constant or Attribute)

Note that if solidification is enabled, the specified Edge Position Lerp will override the Endpoints Weights specified for Outputs, to enforce consistency.

Radiuses

When a solidification axis is selected, lets you set the edge bounds’ remaining two axis as “radiuses”.
Each component shares the same following properties:

Write Radius X/Y/Z
Radius Type
Radius Constant
Radius Attribute