3D registration [message #53767] |
Tue, 01 May 2007 10:25  |
Bita
Messages: 4 Registered: March 2007
|
Junior Member |
|
|
Hi,
I would like to implement an affine transformation for 3D
registration.
I have done a linear rigid transfomation with T3D IDL-function,
but how can I do the shear operations?
Thanks
Bita
|
|
|
Re: 3D registration [message #53804 is a reply to message #53767] |
Thu, 03 May 2007 08:34  |
Mike[2]
Messages: 99 Registered: December 2005
|
Member |
|
|
On May 1, 1:25 pm, Bita <rahm...@sbox.tugraz.at> wrote:
> Hi,
> I would like to implement an affine transformation for 3D
> registration.
> I have done a linear rigid transfomation with T3D IDL-function,
> but how can I do the shear operations?
You can use t3d to incorporate translations, scaling, and rotations,
i.e.
t3d, /reset
t3d, translate=[dx,dy,dz]
Then you can multiply by a shear transformation "by hand" (without
t3d):
shear = [ [ 1, Sxy, Sxz, 0 ],
[ 0, 1, Syz, 0 ],
[ 0, 0, 1, 0 ],
[ 0, 0, 0, 1 ] ]
!p.t = shear # !p.t
I think I may be remembering the correct form for a shear
transformation, but don't take my word for it!
Mike
|
|
|