Answers for "Euler angles have a dead zone near 90?"
http://answers.unity.com/questions/44465/euler-angles-have-a-dead-zone-near-90.html
The latest answers for the question "Euler angles have a dead zone near 90?"Answer by Jade
http://answers.unity.com/answers/44620/view.html
<p>I ended up just reorienting my object so that 90 degrees (y-axis) wasn't within the range of readings that I needed (I'm using forward for the primary direction instead of up now). I wouldn't call this an answer, but a workaround. I'd still like to know why this happens, but I also need to move on due to tight deadlines!</p>
<p>Thanks for all of the replies, and if you have more info, I'd love to hear it!</p>Wed, 26 Jan 2011 03:33:29 GMTJadeAnswer by jonas-echterhoff
http://answers.unity.com/answers/44486/view.html
<p>Euler angles have some shortcomings (which is why they are not generally used for internal math in game engines, Quaternions are preferred for that), and since there are multiple ways to represent a specific rotation, you are not guaranteed to get continuous results for rotation along any axis.</p>
<p>However, you should be able to calculate the rotation around an arbitrary axis yourself. This should give you the angle of a vector around the z-Axis for example (un-tested):</p>
<pre><code>var vector = transform.direction;
var angle : float = Mathf.Atan2(vector.x, vector.z) * Mathf.Rad2Deg;
</code></pre>Tue, 25 Jan 2011 09:23:26 GMTjonas-echterhoff