function lightViewPosition( light ) {

	const data = getLightData( light );

	return data.viewPosition || ( data.viewPosition = uniform( new Vector3() ).setGroup( renderGroup ).onRenderUpdate( ( { camera }, self ) => {

		self.value = self.value || new Vector3();
		self.value.setFromMatrixPosition( light.matrixWorld );

		self.value.applyMatrix4( camera.matrixWorldInverse );

	} ) );

}
TSL function for getting the position in view space for the given light.

@tsl
@function
@param {Light} light - The light source.
@returns {UniformNode<vec3>} The light's position in view space.