When PCG assets are assigned to an World Partition - Data Layer and a HLOD Layer, the PCG graph generates the actors and assigns them to the same data layer and HLOD layer.
Using Data Layers
In the example below, there are two partitioned PCG volumes. One generates rock meshes and is assigned to the DL_Rocks data layer. The other generates tree meshes and is assigned to the DL_Trees data layer.
Selecting the generated meshes in the Data Layers window shows that the rocks are automatically assigned to DL_Rocks and the trees are automatically assigned to DL_Trees.
Data Layer Settings for Spawn Actor and Create Target Actor Nodes
The Spawn Actor and Create Target Actor nodes each have a setting called Data Layer Source Type that controls how the node assigns actors to a Data Layer.
The Data Layer Source Type can be set to the following options:
Self: The Spawn Actor or Create Target Actor node assigns the same Data Layers to the spawned actors as the source PCG Component actor.
Data Layer References: The node assigns Data Layers using an input Param Data set by the Data Layer Reference Attribute.
The Spawn Actor and Create Target Actor nodes support filtering using the Included Data Layers and Excluded Data Layers properties, which can be inputs or direct references.
There is also an Add Data Layers category where you can specify additional Data Layers to assign, either as input or as direct references.
Get Actor Data Layers
The Get Actor Data Layers node reads the ActorReference attribute from the inputs, and then outputs all the Data Layers used by those inputs into the DataLayerReference attribute. The output is a single Param Data that contains one entry per Data Layer asset.
Partition By Actor Data Layers
The Partition By Actor Data Layers node takes Point Data as input, and outputs one or more partitions of Point Data based on the Data Layers in the input Point Data.
The node resolves input points using an ActorReference attribute to get the Data Layers used by the Actor. Then it creates a Point Data and a Data Layer Partition for every combination of those Data Layers found on the input.
To include or exclude data layers from the process, use the Included Data Layers and Excluded Data Layers inputs on the node, or use DataLayer asset references in the node settings.
When using Included Data Layers, any other Data Layer will be ignored. When using Excluded Data Layers, all Data Layers will be considered except for the excluded Data Layers.
Example 1
The input data has three Points that point to three different actors. One actor uses DataLayerA, and the other two actors use DataLayerB.
The output will include two Point Data, and two Data Layer Partitions (stored as Param Data).
The first Point Data will contain the point that is using DataLayerA. The second Point Data will contain both points that are using DataLayerB.
The first Data Layer Partition will contain one entry with a DataLayerReference attribute pointing to the DataLayerA asset. The second partition will contain one entry with a DataLayerReference attribute pointing to the DataLayerB asset.
Example 2
The input has the following Points:
a Point that resolves to DataLayerA
a Point that resolves to DataLayerB
a Point that resolves to both DataLayerA and DataLayerB
The output will include three Point Data with a single point each, and three Param Data.
The first Point Data will contain the point that is using DataLayerA. The second Point Data will contain the point that is using DataLayerB. The third Point Data will contain the point that is using both DataLayerA and DataLayerB.
The first Data Layer Partition will contain one entry with a DataLayerReference attribute pointing to the DataLayerA asset. The second partition will contain one entry with a DataLayerReference attribute pointing to the DataLayerB asset. The third partition will contain two entries, one that points to the DataLayerA asset and one that points to the DataLayerB asset.
Using HLOD Layers
In the example below, there is a Surface Sampler that generates rock meshes.
The PCG Graph that contains the sampler is set to assign all of its components and actors to an HLOD layer called MyHLODLayer.
Selecting the generated meshes shows that the generated rocks are automatically assigned to MyHLODLayer.
HLOD Settings for Spawn Actor and Create Target Actor Nodes
The Spawn Actor and Create Target Actor nodes each have a setting called HLODSource Type that controls how the node assigns actors to an HLOD Layer.
The HLODSource Type can be set to the following options:
Self: The Spawn Actor or Create Target Actor node assigns the same HLOD Layer to the spawned actors as the source PCG Component actor.
Reference: The node assigns an HLOD Layer through a direct reference to the HLOD Layer on the node settings.
Template: The node uses the HLOD Layer reference from its Template Actor.
