1、Three.js uses the right handed system and this means counter clockwise is default rotation.
2、i add a cube, and then it display as follows.
3、if i do a rotation as follows
cube.rotation.y += Math.PI / 6;
it displays as follows, which also is my expect
4、but if i do the rations as follows
cube.rotation.set(Math.PI, 0, Math.PI, "XYZ"); cube.rotation.y += Math.PI / 6;
it seems the direction of rotation changes to be clockwise;
you can also check the sandbox by: 骰子 (forked) - CodeSandbox
why does it happen, how can I know the direction exactly