You can rotate the tangent vectors around the selected location, while keeping their magnitude unchanged. To do so:
| 1 | Select the surface by clicking on the location you want to edit. A cross handle will be displayed in such location. |
| 2 | Click again on the selected location, which is the center point of the cross handle and has a marker on it. |
| 3 | Right-click on one of the tangent vectors and select Set Tan Direction. The handle starts moving along as you move the mouse. Click to stop the rotation and fix the handle at its new direction. or Click on one of the tangent vectors of the cross handle middle way between the selected location (the central point of the handle) and an end point. The handle starts moving along as you move the mouse, while holding down the mouse button. Release the mouse button to stop the rotation and fix the handle at its new direction. The shape of the surface will be modified.  |