will it be possible to move, scale and rotate the image plane in the viewport like a stencil ?

It’s difficult to tweak the picture with the parametres.

Hold down the E-key and
- left click: rotate
- middle click: translate ‘xy’
- right click: translate ‘z’
- left+middle click: scale

I assume this is what you meant? :)

“Men honor what lies within the sphere of their knowledge, but do not realize how dependent they are on what lies beyond it”
--Chuang Tzu

http://www.maphart.com
http://maph.cgsociety.org/gallery/

Marvelous !!! I love mudbox !!!

thx a lot !

(The hotkey “X” works in the same way to transform meshes.)