View Full Version : Rotation Mystery

09-23-2003, 03:02 AM
I am trying to disply a 3-axes coordinate systems similar to one appears in 3d modelers.
They are displyed correctly as right handed system. However, when rotting them some how, the system is flipped to left handed, and agin to right handed in arbitrary manner.
The rotation is performed by dragging the mouse over the view pane.
Could you please inform me of what is going on?

The 3-axes-drwing code is compiled in a display list.

glRotatef(pitch, 1.0, 0.0, 0.0);
glRotatef(yaw, 0.0, 1.0, 0.0);

09-23-2003, 07:10 AM
Gimbal Lock ?


09-23-2003, 04:45 PM
So... When you try rotating them with your mouse they rotate in the wrong direction?

09-24-2003, 03:11 AM
I think Gimbal phenomena has to do with losing degrees of freedom.
Could you please show me how it works in flipping the system to left-handed?

09-24-2003, 04:37 AM
Gimbal Lock was just a guess. With the little information you give it's hard to track down the problem.

Have a look at your code - somewhere you must be flipping an axis yourself.

09-27-2003, 12:44 AM
I found out that it occurs in Softimage XSI too, so my program will never be better than Avid software. Why sould I care????