# 2D Isometric GridGraph and Rotation problem

I am trying to build a 2D Isometric GridGraph. I am able to build it in a 3D scene where the the climb-axis is Y and I use isometric angle 35.264 and Y-rotation = 45. See screenshot: http://i.imgur.com/7yuLtLp.png

However, Unity 2D is X/Y based and the climb-axis needs to be Z. I rotate via the X-axis 90 degrees (also tried -90), Isometric angle is 35.264 and Z-axis rotation = 45. When I change that Z-axis -rotation to 45, the Y-axis rotation changes to 311. See screenshot: http://i.imgur.com/QbYLXHB.png

Continued trying to look at this, seems like some sort of gimbal-lock / Matrix / Quaternion computation error. As I mentioned in the 2nd paragraph, I change the z-axis rotation of the GridGraph and once I press enter, the Z-axis is set to 0 and changes the Y-axis changes its value, as in the above, Z-axis changed to 0 (from setting 45) and the Y axis, which was not touched changed to 311.

Here’s a small video showing what I am seeing:

Attemping to rotate around the Z-axis just rotates around the Y-axis once the X-axis is rotated by 90 degrees. Actually has nothing to do with the GridGraph being isometric either.

Hi

Yeah, what you are seeing is a kind of gimbal lock I think. So not really something I can do anything about (unless you want to be entering quaternions manually).
If you try the same rotation on a unity transform, it shows the same behaviour (i.e setting the rotation to (90,0,0) will cause the Y and Z fields to rotate it around the same axis).

Thanks - had not noticed that before. Hopefully Unity will allow options for 2D developers to change coordinate systems in the future - Melv May has said he worked on it but didn’t make it into the patches. For now, I’ve just rotated my 2D sprites 90 degrees in x so I can use my GridGraph with no rotation. This works for me because I am not using any 2D physics or rotations.