You can modify the magnitude of tangent vectors while keeping their direction 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 Magnitude. The handle extension changes as you move the mouse. Click to fix the new lenght of the vector. or Click on one of the tangent vectors of the cross handle in a location that is 3/4 of the length between the center point of the handle and an end point. The handle extension changes as you move the mouse, while holding down the mouse button. Release the mouse button to fix the new length of the vector. The shape of the surface will be modified  |