threeify-hash.js

let arrayBuffer = new ArrayBuffer( 12 * 16 );
let floatArray = new Float32Array( arrayBuffer );
let intArray = new Int32Array( arrayBuffer );

 function hashFloat1( v ) {
    floatArray[0] = v;
    return intArray[0];
}

 function hashFloat2( v0, v1 ) {
    floatArray[0] = v0;
    floatArray[1] = v1;

    // https://github.com/BabylonJS/Babylon.js/blob/master/src/Maths/math.vector.ts#L42
	let hash = intArray[0];
    return (hash * 397) ^ (intArray[1]);
}

 function hashFloat3( v0, v1, v2 ) {
    floatArray[0] = v0;
    floatArray[1] = v1;
    floatArray[2] = v2;

    // https://github.com/BabylonJS/Babylon.js/blob/master/src/Maths/math.vector.ts#L718
    let hash = intArray[0] | 0;
    hash = (hash * 397) ^ (intArray[1] | 0);
    return (hash * 397) ^ (intArray[2] | 0);
}

 function hashFloatArray( elements ) {
    for( let i = 0; i < elements.length; i ++ ) {
        floatArray[i] = elements[i];
    }
    // https://github.com/BabylonJS/Babylon.js/blob/master/src/Maths/math.vector.ts#L4017
    let hash = intArray[0] | 0;
    for (let i = 1; i < 16; i++) {
        hash = (hash * 397) ^ (intArray[i] | 0);
    }
    return hash;
}
hashFloat3( 0.127, 0.255, 0.512 );
hashFloat3( 0.127, 0.512, 0.512 );
hashFloat3( 1.127, 0.512, 0.512 );
hashFloat3( -0.127, 0.512, 0.512 );