Purpose
Usage
Click the add points button to activate it.
To insert a point between two other control points, click on the control
polygon between the two points.
To add a point at the end or beginning of a curve, click on a position in the
window but not on a control polygon. The point will then be added to the
nearest beginning or end point.
The new point can be moved immediately to the correct position using the mouse
(while keeping the middle mouse button pressed) or keyboard (if keyboard is
active). Click the left mouse button again to confirm the position of the new point (not necessary is keyboard is active).
Comments
If the add change button is activated, new points added will change the shape
of the original curve.
If add change is deactivated, new points will be added without changing the
shape of the original curve.
