#Rectangle

Key R. Three ways to define it, the switch is in the top bar.

• By two corners — click the opposite corners.
• From the centre — the first click sets the centre, the second a corner.
• By three points — two points set a side (and the tilt), the third sets the width. This is the only way to get a tilted rectangle without rotating it afterwards with constraints.

#What you get

Four segments with constraints: pairwise parallel and perpendicular, the corners match. That is why a rectangle needs only two dimensions — width and height — to become fully defined.

#A hint

The centre rectangle is handy when the part is symmetric about the origin: the centre lands on zero and symmetry comes for free, without a pair of dimensions.