Trimming or extending a surface

After starting the Trim/Extend Surface command, proceed as follows.

1 In the Mode drop-down list, select the method to be used:
  • Parameter
    to change the range of the surface parameters so that the limits of the range differ from the original limits limits (this mode does not apply to surface boundaries deriving from a trimming operation: in such cases selection is not enabled)
  • Tangency
    to indicate a numeric value corresponding to the length of the arc to be added to the specified boundary of the surface while maintaining tangency continuity.

Extending a surface by changing the range of its parameters

2 Select the surface.



To change the selected surface, right-click on Surface, choose Reset in the context menu and select another surface.

The U1, U2, V1 and V2 mini-dialog boxes — respectively corresponding to the starting and ending values of the U and V parameters —  are displayed.



As you can see a handle is displayed together with each mini-dialog, so that you can change the value of the corresponding parameter either by explicitly specifying its value or by dragging the corresponding handle, thus interactively controlling the new shape of the modified surface.
3 Drag the handle or type in the value(s) you want to change.



A preview is immediately displayed (interactively, if you drag the handle; as soon as you enter the value by hitting the TAB key in the other case)
4 Click or to confirm your selections and modify the shape of the object.



Click to discard your changes.

Extending a surface maintaining its tangency along a boundary

2 Select the boundary along which you want to extend the surface.



To change the selected boundary, right-click on Boundary, choose Reset in the context menu and select another boundary.

The Length mini-dialog box and the corresponding handle are displayed, so that you can change the length either by explicitly specifying its value or by dragging the corresponding handle, thus interactively controlling the new shape of the modified surface.
3 Drag the handle or type in the desired value: a preview of the modified surface is immediately displayed (interactively, if you drag the handle; as soon as you enter the value by hitting the TAB key in the other case):
4 Click or to confirm your selections and modify the shape of the object.



Click to discard your changes.