A class containing utility functions for [page:BufferGeometry BufferGeometry] instances.
		
		geometry -- A [page:BufferGeometry BufferGeometry] instance, which must have index, position, normal, and uv attributes.
		Calculates and adds tangent attribute to a geometry.
		
		geometries -- Array of [page:BufferGeometry BufferGeometry] instances.
		useGroups -- Whether groups should be generated for the merged geometry or not.
		Merges a set of geometries into a single instance. All geometries must have compatible attributes.
		If merge does not succeed, the method returns null.
		
		attributes -- Array of [page:BufferAttribute BufferAttribute] instances.
		Merges a set of attributes into a single instance. All attributes must have compatible properties
		and types, and [page:InterleavedBufferAttribute InterleavedBufferAttributes] are not supported. If merge does not succeed, the method
		returns null.
		
		attributes -- Array of [page:BufferAttribute BufferAttribute] instances.
		Interleaves a set of attributes and returns a new array of corresponding attributes that share
		a single InterleavedBuffer instance. All attributes must have compatible types. If merge does not
		succeed, the method returns null.
		
		geometry -- Instance of [page:BufferGeometry BufferGeometry] to estimate the memory use of.
		Returns the amount of bytes used by all attributes to represent the geometry.
		
		geometry -- Instance of [page:BufferGeometry BufferGeometry] to merge the vertices of.
		tolerance -- The maximum allowable difference between vertex attributes to merge. Defaults to 1e-4.
		Returns a new [page:BufferGeometry BufferGeometry] with vertices for which all similar vertex attributes
		(within tolerance) are merged.
		
[link:https://github.com/mrdoob/three.js/blob/master/examples/js/utils/BufferGeometryUtils.js examples/js/utils/BufferGeometryUtils.js]