Fresnel0ToIor = ( fresnel0 ) => {

	const sqrtF0 = fresnel0.sqrt();
	return vec3( 1.0 ).add( sqrtF0 ).div( vec3( 1.0 ).sub( sqrtF0 ) );

}
Applies mipped bicubic texture filtering to the given texture node.

@tsl
@function
@param {TextureNode} textureNode - The texture node that should be filtered.
@param {Node<float>} [lodNode=float(3)] - Defines the LOD to sample from.
@return {Node} The filtered texture sample.