A computer-implemented method manipulates a 3D object in a 3D scene of a computer-aided design system, by: (i) displaying a 3D object having a center of rotation in the 3D scene on a screen; (ii) displaying in the 3D scene a rotation manipulator (RM) having three areas (RA1, RA2, RA3) perpendicular to each other, and each area (RA1, RA2, RA3) corresponding to a rotation plane, and (iii) activating the rotation manipulator. The rotation manipulator (RM) follows the cursor (C) on the screen. The rotation manipulator is activated by locking its location on the screen on an initial press point (PP). One rotation plane is selected by displacing the cursor (C) to the area (RA1, RA2, RA3) corresponding to said plane. A rotation manipulation is performed according to the displacement of the cursor (C) on the screen.