ARCS

Arcs have a more complex behaviour than curves. They behave differently depending on whether or not they have been selected (see selecting an object). They also have end points, non-end points (a point on the arc which is visible and not at either end of the arc), and an inside and outside.

If the arc is selected the two end points are shown connected to the arcs centre via two lines.

• while the arc is not selected:
• grabbing the arc at one of its ends changes the length of the arc and its centre point without changing its angle and rotates the arc about its other end point (i.e. the centre point will change)
• while the arc is selected:
• grabbing the arc at one of its ends changes the length of the arc and its angle without changing its centre point or other end.
• grabbing the centre of the arc (where the two lines meet at the centre), changes the size of the arc and its angle.
• whether the arc is selected or not:
• grabbing the arc from its outside moves the arc without changing its length or angle
• grabbing the arc from its inside keeps the end points in their current position and changes the size of the arc and its angle