i already snet my problem.i didnt get reply.
may be my question was not clear.
thats why i am sending one more.
i am working in openGL’s NURBS concept.
by using nurbs concept i am drawing curves and surfaces.
actually i wanto get peeling effect from the cube surface by moving this nurbs surfaces.
for that i am moving control points of that nurbs surfaces.
i.e hwen i am pressing one key on the keyboard i am moving the control points.
i want to move the control point the mouse pointer
on the dispaly window wherever i move the mouse pointer that specific control point should move to that point.
thsi si my problem.