Snapping and inference
The shelf along the bottom of the tray holds the controls that decide what your pointer snaps to. Hover a control for its name.
To snap to round distances
Click Snap amount and choose Off or one of 10, 25, 50, 100, 250 and 500 mm.
To choose what you snap to
Snap to names the kind of thing you're drawing (walls, items or shapes) and sets its mode. Walls offer Lines, Angles and Off; items and shapes offer Lines and Off.
To show or hide the grid
Click Grid to cycle through On, Soft and Off. Thin lines switches thin plan lines on and off.
To change scale or units
Plan scale shows the current ratio, such as 1:50, and opens a menu of others. Measure in switches between m, mm and ft/in.
On a sheet and in Diagram view these controls are greyed out, with the reason shown. Magnetic snap sits on the Canvas tab of the Display row.