I’m trying to understand the rotationX/Y/Z functions but the results are not consistent and wonder why not a single user had this problem except myself?  (Perhaps, I need some simple basic knowledge for this:lol:)

Anyway, what I found is that rotationZ rotages always globally while rotationX is always local and rotationY is half local and half global.

It’s somewhat difficult to explain in words so I put my code (attachment) .  Please have a look at and run (if you care;-P) it.

For example, if I rotate around X-axis a bit it perfectly rotates around X-axis and if try to rotate around Y-axis it doesn’t rotate around Y-axis, not globally nor Parent/Local, and if try to rotate around Z-Axis it rotates perfectly around the global Z-axis.
If you play around rotating X/Y/Z, you will clearly see what I mean.

I found if I try to rotate around X, it always rotates around the local X-axis perfectly.
If I try to rotate around Z, it always rotates around the Global Z-axis perfectly.
If I try to rotate around Y, it rotates with no rules.

Is it a bug?  (if then why nobody found it yet?)
If not, why does it works that way?  What did I miss?

Please help, I’m wrestling with this hardly and feeling I’m losing the wrestle.

=== part of the code I used ===
case 38: // UP
  container.rotationX += 9;
  break;

case 40: //  DOWN
  container.rotationX -= 9;
  break;

case 39: // RIGHT
  container.rotationY += 9;
  break;

case 37: // LEFT
  container.rotationY -= 9;
  break;

case 33: // PAGE UP
  container.rotationZ += 9;
  break;

case 34: // PAGE DOWN
  container.rotationZ -= 9;
  break;
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