Edit Bar controls: none.
This tool allows you to snap picked points to the nearest quadrant of the indicated arc or circle.
By default, the quadrants are the points are at zero, 90, 180 and 270 degrees from the arc centre, but you can override the number of points (usually 4) from Arc Segments in Snap Settings.
The cursor is modified to show “Quad” to indicate that the snap mode is active.
The Snap To Quadrant tool can only be used with arcs and circles (both normal and construction).
Related topics: Snap Modes and Lock Modifiers