code: public Vector2f positiveX(Vector2f dir) {
          float s = m00 * m11 - m01 * m10;
          s = 1.0f / s;
          dir.x =  m11 * s;
          dir.y = -m01 * s;
          return dir.normalize(dir);
      }
docs: /* (non-Javadoc)
  @see org.joml.Matrix3x2fc#positiveX(org.joml.Vector2f)