Extend a curve
Extend a NURBS curve from a selected endpoint by adding and positioning a control point.
Before you start
Enter Curve Edit Mode on an existing curve. Start with an endpoint of an open curve to make the extension easy to understand.
Use the operation
Extend a curve by adding a connected span.
- Select an endpoint, leaving unrelated points unselected.
- Press E to begin extrusion, then move the selected point to shape the new span.
- Confirm the move, inspect the added connection, and repeat only after the new span is correctly positioned.
Controls and choices
| Controls | What changes |
|---|---|
| Extrude versus move | E adds supporting point structure for an extension. G moves the existing selection without adding a span. |
| Selection boundaries | The operation follows boundaries in the ordered control-point sequence. Multi-point or cyclic selections can produce a different result from extending one open endpoint. |
| Thickness | Point extrusion extends the path. Use the Curve Data bevel settings to give that path a tube-like surface. |
Try it in your scene
Select one curve endpoint, extrude it, and place the new point. Inspect the extended path before continuing.
Check the result
Check that the new span extends in the intended direction and does not create a folded or nearly zero-length segment. Undo and reposition if necessary.
Practice in Show3D
Open the editor and follow the steps with your own scene.