CIRCLES AND ELLIPSES

Empty circles / Toggle LEFT CLICK (Key:'C') Selects the empty circles or ellipse as the active drawing tool. RIGHT CLICK (Key:Ctl+'C') Select shape and operation mode. Center/radius mode : Position the center of the cercle and maintain the mouse button to select its radius. Corners mode : Press the mouse button at a corner and release at the other corner of a rectangle in which the circle or ellipse is inscribed.