getContext() {

		const { backdropNode, backdropAlphaNode } = this;

		const directDiffuse = vec3().toVar( 'directDiffuse' ),
			directSpecular = vec3().toVar( 'directSpecular' ),
			indirectDiffuse = vec3().toVar( 'indirectDiffuse' ),
			indirectSpecular = vec3().toVar( 'indirectSpecular' );

		const reflectedLight = {
			directDiffuse,
			directSpecular,
			indirectDiffuse,
			indirectSpecular
		};

		const context = {
			radiance: vec3().toVar( 'radiance' ),
			irradiance: vec3().toVar( 'irradiance' ),
			iblIrradiance: vec3().toVar( 'iblIrradiance' ),
			ambientOcclusion: float( 1 ).toVar( 'ambientOcclusion' ),
			reflectedLight,
			backdrop: backdropNode,
			backdropAlpha: backdropAlphaNode
		};

		return context;

	}
Returns a lighting context object.

@return {{
radiance: Node<vec3>,
irradiance: Node<vec3>,
iblIrradiance: Node<vec3>,
ambientOcclusion: Node<float>,
reflectedLight: {directDiffuse: Node<vec3>, directSpecular: Node<vec3>, indirectDiffuse: Node<vec3>, indirectSpecular: Node<vec3>},
backdrop: Node<vec3>,
backdropAlpha: Node<float>
}} The lighting context object.