[Core] Rotation : fix gimbal lock handling

[0penBrain]

• fix Euler representation string on GUI

Forum discussion

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[yorikvanhavre]

In that case I feel the following 3 fields should also be inverted...

Won't ZYX be confusing for many users? If we talk about 3 axes, the logical sequence 99% of users will think of is XYZ. Shouldn't we somehow, make it clearer that XYZ does NOT translate to yaw-pitch-roll? For ex in the drop down list, be able to switch?

[0penBrain]

@yorikvanhavre this is quite a complicated topic to me. It really depends what is your knowledge and understanding about Euler angles. I'll do a proposal later this day.

[0penBrain]

Now how it looks like :

[yorikvanhavre]

That looks pefect! Totally understandable by everybody. Thanks!!