Image bm819.GIF Rotation around Z-Axis
The rotation around Z-axis element is a numeric variable defining an active object rotation around the Z axis. The Z axis is the axis pointing from the coordinate system origin forward (from the viewer). The direction of rotation around the Z axis is defined by the left hand rule: The left hand thumb point in the Z axis direction (i.e. forward form the viewer), the bent fingers indicate the direction of positive rotation. As a consequence, a positive value of the direction of rotation around the Z axis will cause the object's top side to move to the left and the object's bottom side to the right. This is also depicted in the icon picture of the Z rotation. The rotation value is adjusted to range in the 0 through 2*pi interval. By reading the variable one will always get a value from this interval. A rotation is carried out after a scale transformation and before a translation transformation. The rotation succession related to the individual axes can be determined by the order of rotations element.

Full Html Context Help of The Peter - Gemtree Software & Children Programming