When measure tools are activated by selecting Ruler in the side menu, Ruler appears in the preview window and W (horizontal width), H (vertical height), D (depth), and the angle (angle between the line and X axis in the positive direction) icons appear in the measure tools information panel. The initial value is 0 and the unit of measure is the one used by the present working file. The mouse becomes the icon of the ruler in the preview window. As the mouse moves, the value of the information panel changes.
Click another tool icon to cancel the display of the measure tool.