Instructions in advance , my unity version is 5.4.1f1,and I am a Chinese that my English is poor，I hope you can have the patience to read this passage ,thanks.
In my project ,I want to rotating a gameobject ,but I found some things that I can’t understand:
When I change a gameobject’s rotation in inspector of the gameobject ,I found if the initial size is (0,0,0), I change any axis ,the gameobject is rotating according to the axis accurately and I can find it in Scene.
But if the initial size is (20,0,0),I change Z,gameobject can rotating according to the axis that now gameboject’s axis in the Scene, but if I change Y,the rotate’s according isn’t now gameobject’s axis. in the Scene,I observed at the gameobject is rotating according to the (0,0,0)'s axis.
Why I change the Z ,gameobject is all rotating according to itself,but I change Y,gameobject is rotating according to the other one coordinate system? It isn’t the world coordinate system,I try to implementation in c#,whether I use Space.Self or Space.World,the question is appear.
Who can give me some hints?Thanks,I feel sorry for my language proficiency.
It happens because Gimble Lock … Here when you rotate GameObject to 20 degrees Z axis loses the “Degree of Freedom”. So One will rotate Globally and Other will rotate locally. When your X is set to 90 or 270 degrees Y axis and Z axis will do same rotation. You should always rotate with respect to world space though.
Here is another useful and more detailed answer you may find helpful