единство, почему нет преобразования.

//The reason that there is a transform.up, right and forward, 
//and not a transform.down, left and back,
//is because you can just add a minus to the existing ones to invert them.

//A transform.down could be -transform.up
//A transform.left could be -transform.right
//A transform.back could be -transform.forward
CharliePagel says: You're cool!