Quaddefines a four sided, two dimensional shape. The local height of the
Quaddefines it's size about the y-axis, while the width defines the x-axis. The z-axis will always be 0.
Quadrepresents a rectangular plane in space defined by 4 vertices. The quad's lower-left side is contained at the local space origin (0, 0, 0), while the upper-right side is located at the width/height coordinates (width, height, 0). @author Kirill Vainer