The question now, is the user coordinate the world coordinates of its own, known users turn to the world coordinate system, there are only two angles, PI/2 and 3 * PI/2, user ahead of PI/2, back to 3 * PI/2, strives for the conversion of specific methods or functions, such as matrix, the four elements such as content, implementation and U3D conversion function is consistent, the transform. The position; Consistent,