depending on you’re applying your transformations [i.e. keeping the rotated matrix] you could be applying what you may think is a controlled angle but REALISTICALLY you’re applying a rotation on an already rotated “world”.

if you could be a bit more descriptive on how you’re applying the rotations, that might help.

best regards

-berto :yes:

Hi,

I have a system where we load objects into the scene. The following operations are allowed. All inputs are given using mouse.

1. rotate individual objs

2. translate individual objs

3. rotate the entire system about the origin

4. translate the entire system

To do this, I keep the following data

And I do the following in the display function

foreach object i

1. apply rotation using quaternion Q

2. translate using parameters Tx,Ty,Tz

3. rotate using quaternion qi

4. translate to center using Cix,Ciy,Ciz

this seems to work fine for some transformations, but after certain amount of rotation, I find that the objects move in opposite direction. Can some one tell me what is wrong with my method? I would be glad to an alternative method.

Thanks!