3.11 Dimensions on a drawing

M takes the ruler out inside the editor, and two clicks put a dimension on the drawing. It snaps to what the pen snaps to — corners, centres, the axes through the first point, then the grid, with Alt to suppress — so corner to corner is exactly corner to corner rather than however near you clicked. Esc abandons the one in progress, and again puts the ruler away and the pen back in your hand.

A dimension belongs to the drawing. It is measured in the sketch’s own coordinates, so it rides the plane: move the wall a layout is drawn on and the numbers go with it, and deleting the sketch takes them too. It looks and behaves like a scene ruler otherwise — click it and press Del to remove one, in the editor or out in the venue. Clicking one takes the Select tool, and only Select: with a pen in your hand a click near a dimension draws, and with the ruler out it measures. That is why taking the ruler out also puts the pen down — measure, Esc, click what you just made, and it is yours.

A selected dimension grows a grip at each end, and dragging one re-measures from there — onto a different corner, or out to a centre, snapping to everything the ruler snapped to and to the axes through the other end. Alt takes it off the grid, and the drag is one Ctrl+Z. The grips appear only while it is selected, and that is deliberate: an end usually sits exactly on the corner it was measured to, so ends you could always grab would mean that measuring a corner quietly cost you the ability to drag it.

Set Dimensions to Hidden in the inspector to put them away without deleting them; it is the same switch as Linework, for the other half of the drawing, and it is stored in the file rather than in your viewport preferences.