header
header: { 
    average: Float32Array; 
    childFlags: number; 
    debug1: number; 
    eigenVector: [Float32Array, Float32Array, Float32Array]; 
    eigenVectorLength: [number, number, number]; 
    indices: Int32Array; 
}
Type declaration
average: Float32Array
childFlags: number
debug1: number
eigenVector: [Float32Array, Float32Array, Float32Array]
eigenVectorLength: [number, number, number]
indices: Int32Array