Specifying shape properties
Each shape has its own tab on the Inspector on which you can set properties.
All shape objects have an anti-aliasing property that you can set. Anti-aliasing smooths the appearance of jagged edges between solid colors. When an object has curves or lines that are drawn at an angle, jagged edges might appear. With vertical or horizontal straight lines, jagged edges do not appear.
Rounded rectangle and elliptical arcs have additional properties you can set to control the shape of those objects.