setup( builder ) {

		const { normalMapType, scaleNode } = this;

		let normalMap = this.node.mul( 2.0 ).sub( 1.0 );

		if ( scaleNode !== null ) {

			normalMap = vec3( normalMap.xy.mul( scaleNode ), normalMap.z );

		}

		let outputNode = null;

		if ( normalMapType === ObjectSpaceNormalMap ) {

			outputNode = transformNormalToView( normalMap );

		} else if ( normalMapType === TangentSpaceNormalMap ) {

			const tangent = builder.hasGeometryAttribute( 'tangent' );

			if ( tangent === true ) {

				outputNode = TBNViewMatrix.mul( normalMap ).normalize();

			} else {

				outputNode = perturbNormal2Arb( {
					eye_pos: positionView,
					surf_norm: normalView,
					mapN: normalMap,
					uv: uv()
				} );

			}

		}

		return outputNode;

	}
The normal map type.

@type {(TangentSpaceNormalMap|ObjectSpaceNormalMap)}
@default TangentSpaceNormalMap