Chapter 461: ReferenceNode

Core Idea

This type of node establishes a reference to a property of another object. In this way, the value of the node is automatically linked to the value of referenced object. Reference nodes internally represent the linked value as a uniform.

Key Concepts

count : number: When the linked property is an array, this parameter defines its length.
group : UniformGroupNode: The uniform group of the internal uniform.
name : string: An optional label of the internal uniform node.
node : UniformNode: The uniform node that holds the value of the reference node.
object : Object: The object the property belongs to.
properties : Array.<string>: The property name might have dots so nested properties can be referred. The hierarchy of the names is stored inside this array.
property : string: The name of the property the node refers to.
reference : Object: Points to the current referred object. This property exists next to ReferenceNode#object since the final refer…
uniformType : string: The uniform type that should be used to represent the property value.
updateType : string: Overwritten since reference nodes are updated per object.

Reference Tables

Constructor

Signature
`new ReferenceNode( property : string, uniformType : string, object : Object, count : number )`

Properties

Property	Description
`.count : number`	When the linked property is an array, this parameter defines its length.
`.group : UniformGroupNode`	The uniform group of the internal uniform.
`.name : string`	An optional label of the internal uniform node.
`.node : UniformNode`	The uniform node that holds the value of the reference node.
`.object : Object`	The object the property belongs to.
`.properties : Array.<string>`	The property name might have dots so nested properties can be referred. The hierarchy of the names is stored inside this array.
`.property : string`	The name of the property the node refers to.
`.reference : Object`	Points to the current referred object. This property exists next to ReferenceNode#object since the final reference might be updated from calling code.
`.uniformType : string`	The uniform type that should be used to represent the property value.
`.updateType : string`	Overwritten since reference nodes are updated per object.

Methods

Method	Description
`.element( indexNode : IndexNode ) : ReferenceElementNode`	When the referred property is array-like, this method can be used to access elements via an index node.
`.generateNodeType( builder : NodeBuilder ) : string`	This method is overwritten since the node type is inferred from the type of the reference node.
`.getValueFromReference( object : Object ) : any`	Returns the property value from the given referred object.
`.label( name : string ) : ReferenceNode`	Sets the label for the internal uniform.
`.setGroup( group : UniformGroupNode ) : ReferenceNode`	Sets the uniform group for this reference node.
`.setName( name : string ) : ReferenceNode`	Sets the name for the internal uniform.
`.setNodeType( uniformType : string )`	Sets the node type which automatically defines the internal uniform type.
`.setup( builder : NodeBuilder ) : UniformNode`	The output of the reference node is the internal uniform node.
`.update( frame : NodeFrame )`	Overwritten to update the internal uniform value.
`.updateReference( state : NodeFrame	NodeBuilder ) : Object`
`.updateValue()`	Retrieves the value from the referred object property and uses it to updated the internal uniform.

Key Takeaways

ReferenceNode extends: EventDispatcher → Node
Most relevant properties: count, group, name, node.
Key methods: element, generateNodeType, getValueFromReference, label.

Connects To

EventDispatcher: parent class
Node: parent class
Source: src/nodes/accessors/ReferenceNode.js