Represents a third-order spherical harmonics (SH). Light probes use this class to encode lighting information.
Creates a new instance of [name].
An array holding the (9) SH coefficients. A single coefficient is represented as an instance of [page:Vector3].
			[page:SphericalHarmonics3 sh] - The SH to add.
			Adds the given SH to this instance.
		
			[page:SphericalHarmonics3 sh] - The SH to add.
			[page:Number scale] - The scale factor.
			A convenience method for performing [page:.add]() and [page:.scale]() at once.
		
Returns a new instance of [name] with equal coefficients.
			[page:SphericalHarmonics3 sh] - The SH to copy.
			Copies the given SH to this instance.
		
			[page:SphericalHarmonics3 sh] - The SH to compare with.
			Returns true if the given SH and this instance have equal coefficients.
		
			[page:Array array] - The array holding the numbers of the SH coefficients.
			[page:Number offset] - (optional) The array offset.
			Sets the coefficients of this instance from the given array.
		
			[page:Vector3 normal] - The normal vector (assumed to be unit length).
			[page:Vector3 target] - The result vector.
			Returns the radiance in the direction of the given normal.
		
			[page:Vector3 normal] - The normal vector (assumed to be unit length).
			[page:Vector3 target] - The result vector.
			Returns the irradiance (radiance convolved with cosine lobe) in the direction of the given normal.
		
			[page:SphericalHarmonics3 sh] - The SH to interpolate with.
			[page:Number alpha] - The alpha factor.
			Linear interpolates between the given SH and this instance by the given alpha factor.
		
			[page:Number sh] - The scale factor.
			Scales this SH by the given scale factor.
		
			[page:Array coefficients] - An array of SH coefficients.
			Sets the given SH coefficients to this instance.
		
			[page:Array array] - (optional) The target array.
			[page:Number offset] - (optional) The array offset.
			Returns an array with the coefficients, or copies them into the provided array. The coefficients
			are represented as numbers.
		
Sets all SH coefficients to 0.
			[page:Vector3 normal] - The normal vector (assumed to be unit length).
			[page:Array shBasis] - The resulting SH basis.
			Computes the SH basis for the given normal vector.
		
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]