[vox-tech] Success with fltk and SDL_image

[Gabriel G. Rosa]

On Wed, May 12, 2004 at 06:42:34PM -0700, Peter Jay Salzman wrote:
> 
> i was once told that the military uses quaternionic rotations in mission
> critical applications.  not sure if the person was talking out the side
> of their butt or not.  but it sure sounds impressive!   :-)
> 

As you hinted to before, quaternion operations are symmetrical. Wouldn't be
very good if the ballistic targeting system decided to switch the sign of
your rotational axis just because you were targeting a country on the opposite
side of the globe :)

That, well not exactly that, is why I use a quaternion based rotator for my
trackball classes (to handle dragging a 3d scene without it getting backwards
if you spin it too far).

Quaternions sound like the devil when you first try and understand them, but
once you break them down and properly construct your code, it all ends up
coming together in neat little chunks of understandable vector operations.

-Gabe

disclaimer: it's been a while since i've actually altered my quaternion code.