fromQuat2 function

List<double> fromQuat2(List<double> out, List<double> a)

Creates a new mat4 from a dual quat.

@param {mat4} out Matrix @param {ReadonlyQuat2} a Dual Quaternion @returns {mat4} mat4 receiving operation result

Implementation

List<double> fromQuat2(List<double> out, List<double> a) {
  final translation = <double>[];
  final bx = -a[0], by = -a[1], bz = -a[2], bw = a[3], ax = a[4], ay = a[5], az = a[6], aw = a[7];

  final magnitude = bx * bx + by * by + bz * bz + bw * bw;
  //Only scale if it makes sense
  if (magnitude > 0) {
    translation[0] = ((ax * bw + aw * bx + ay * bz - az * by) * 2) / magnitude;
    translation[1] = ((ay * bw + aw * by + az * bx - ax * bz) * 2) / magnitude;
    translation[2] = ((az * bw + aw * bz + ax * by - ay * bx) * 2) / magnitude;
  } else {
    translation[0] = (ax * bw + aw * bx + ay * bz - az * by) * 2;
    translation[1] = (ay * bw + aw * by + az * bx - ax * bz) * 2;
    translation[2] = (az * bw + aw * bz + ax * by - ay * bx) * 2;
  }
  fromRotationTranslation(out, a, translation);
  return out;
}