src/primitives.js
function duplicateVertices(arrays) {
  const newArrays = {};
  Object.keys(arrays).forEach(function(name) {
    const arraySpec = arrays[name];
    const srcArray = getArray(arraySpec);
    const newArraySpec = createArrayOfSameType(arraySpec, srcArray.length);
    copyElements(srcArray, getArray(newArraySpec), 0);
    newArrays[name] = newArraySpec;
  });
  return newArrays;
}
function duplicateVertices(arrays) {
  const newArrays = {};
  Object.keys(arrays).forEach(function(name) {
    const arraySpec = arrays[name];
    const srcArray = getArray(arraySpec);
    const newArraySpec = createArrayOfSameType(arraySpec, srcArray.length);
    copyElements(srcArray, getArray(newArraySpec), 0);
    newArrays[name] = newArraySpec;
  });
  return newArrays;
}
function duplicateVertices ( arrays ) { const newArrays = { } ; Object . keys ( arrays ) . forEach ( function ( name ) { const arraySpec = arrays [ name ] ; const srcArray = getArray ( arraySpec ) ; const newArraySpec = createArrayOfSameType ( arraySpec , srcArray . length ) ; copyElements ( srcArray , getArray ( newArraySpec ) , 0 ) ; newArrays [ name ] = newArraySpec ; } ) ; return newArrays ; }
Creates a duplicate set of vertices

This is useful for calling reorientVertices when you
also want to keep the original available

@param {module:twgl.Arrays} arrays of vertices
@return {module:twgl.Arrays} The dupilicated vertices.
@memberOf module:twgl/primitives
Creates a duplicate set of vertices