On Fri, 18 Feb 2005 10:44:29 -0800, Joe Van Dyk <joevandyk / gmail.com> wrote:
> I have a GnomeCanvas Group that I'm trying to rotate (in 2D).
> 
> I know which direction the "top" of the group should be pointing.
> 
> My initial attempt was
>         affine = Art::Affine.new([Math.cos(180), -Math.sin(180), 0,
> Math.sin(180), Math.cos(180), 0])
>         @group.affine_absolute(affine)
> 
> That was to rotate the object 180 degrees, but it didn't work too
> well.  I'm pretty new to all this matrix transformation / graphical
> stuff.  Could someone tell me if I'm on the right track?
> 

Nevermind, I got it.  Reading through the C LibArt documentation, the
affine matrix needs to be in (x1, y1, x2, y2, x3, y3) format, not (x1,
x2, x3, y1, y2, y3) as I assume.