setupVarying( builder ) {

		const properties = builder.getNodeProperties( this );

		let varying = properties.varying;

		if ( varying === undefined ) {

			const name = this.name;
			const type = this.getNodeType( builder );
			const interpolationType = this.interpolationType;
			const interpolationSampling = this.interpolationSampling;

			properties.varying = varying = builder.getVaryingFromNode( this, name, type, interpolationType, interpolationSampling );
			properties.node = this.node;

		}

		// this property can be used to check if the varying can be optimized for a variable
		varying.needsInterpolation || ( varying.needsInterpolation = ( builder.shaderStage === 'fragment' ) );

		return varying;

	}
This method performs the setup of a varying node with the current node builder.

@param {NodeBuilder} builder - The current node builder.
@return {NodeVarying} The node varying from the node builder.