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[edit] Add new segment

[edit] Description

Once a curve is created you can add new segments, either by extruding it, or placing new handles with CtrlLMB clicks. Each new segment is added to the end of the curve. A new segment will only be added if a single vertex, or handle, at one end of the curve is selected. If two or more vertices are selected nothing is added.

[edit] Opening and Closing a Curve

[edit] Description

This toggles between an open curve and closed curve. The shape of the closing segment is based on the handles. The only time a handle is adjusted after closing is if the handle is an Auto handle. (Open curve) and (Closed curve) is the same curve open and closed.

This action only works on the original starting control-point or the last control-point added. Deleting a segment(s) dosen’t change how the action applies; it still operates only on the starting and last control-points. This means that C may actually join two curves instead of closing a single curve.

[edit] Examples

Open curve.

Closed curve.

Closed curve (Solid).

If the curve is closed the curve is automatically considered a surface with an area. This means it is rendered as a solid (Closed curve (Solid)) and it is renderable using F12.

[edit] Deleting a Segment(s)

[edit] Description

A segment is defined implicitly by its two adjacent control-points. You can’t explicitly select a segment; you must select this two adjacent control-points. Once the control points are selected you can use the Erase menu and select the Segment menu item.

Note, that unlike with meshes, deleting one or ore handles (Selected item) do not “cut” the curve : the adjacent segments are just joined.

[edit] Joining two curves

[edit] Description

Joining curves is really the act of making a segment between the two curves. To join two separated use one control point from each curve. The two curves are joined by a segment to become a single curve. (One curve joined) is the result of joining (Two curves). The segment, labelled “S”, is the new segment joining the two curves. We use F for the hotkey because it is similar to making a new Face in a mesh.

Two curves.

One curve joined.

You can not close a curve by joining the curves; you must Close the curve. You will get the error “Can't make segment” when you attempt to join using the starting and last control-point. For example, in (One curve joined) you must use Close to close the curve.