function copy$3(out, a) {
    out[0] = a[0];
    out[1] = a[1];
    out[2] = a[2];
    out[3] = a[3];
    return out;
  }
Copy the values from one vec4 to another

@param {vec4} out the receiving vector
@param {ReadonlyVec4} a the source vector
@returns {vec4} out