You can modify both the magnitude and the direction of tangent vectors. 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 Tangent. The handle starts moving along as you move the mouse. Click in the position defining the new desired direction and magnitude for the vector. or Click on the tangent vector close to one of its end points. The handle starts moving along as you move the mouse while holding down the mouse button. Release the mouse button in the position defining the new desired direction and magnitude for the vector. The shape of the surface will be modified.  |