Yeah and a second think i would like to ask if someone can translate this ...
// we can prevent rotation that takes any points out of the plane by clamping a point on the
// object that is on the line through the origin of the object with the same vector as the
// plane normal. The clamp is to another plane that is parallel to the first, offset by the
// plane normal vector. Rotations around either of the axes orthogonal to the plane normal
// will be prevented because they take the object point off that parallel plane.
from here http://newtondynamics.com/wiki/index.ph ... r_rotation ... to some official english , cause i cant decode a thing from here