Class

• <DRM Stamp Behaviour>

Superclass

• <DRM SEDRIS Abstract Base>

Subclass

• None.

Definition

An instance of this DRM class specifies that the <DRM Geometry Hierarchy> instance of which the <DRM Stamp Behaviour> instance is a component rotates automatically with the viewpoint of a a 3D graphics application at the time that the environmental object assigned the <DRM Stamp Behaviour> instance is rendered, attempting to continually face the viewer.

The <DRM Geometry Hierarchy> instance rotates about the u, v and/or w axes, within the specified angular limits. The centre of rotation is specified by the <DRM Location 3D> component. The axes are positioned at the centre of rotation, aligned with the equivalent SRF axes. Geometry with a <DRM Stamp Behaviour> instance is normally planar in nature and is considered to face along the normal of that plane.

If the clockwise_limit of the rotation data for an axis is set to +∞ and its counterclockwise_limit is set to -∞, the aggregating <DRM Geometry Hierarchy> instance can rotate freely about that axis. If all axis limits are set in this way, the <DRM Geometry Hierarchy> instance rotates freely in any direction about the centre of rotation.

The u_axis_limits field specifies the angular limits around the u axis.

The v_axis_limits field specifies the angular limits around the v axis.

The w_axis_limits field specifies the angular limits around the w axis.

Class diagram

Figure 6.325 — DRM_Stamp_Behaviour

Constraints

• <DRM Stamp Behaviour> constraints
• Publishable object

Example(s)

• Consider a <DRM Union Of Primitive Geometry> instance containing a single textured <DRM Polygon> instance that is rotating freely about the w axis to represent a tree. The <DRM Union Of Primitive Geometry> instance in this example has a <DRM Stamp Behaviour> component, with u_axis_limits and v_axis_limits set to 0,0 for both the clockwise_limit and counterclockwise_limit, and w_axis_limits set to +∞ for clockwise_limit and -∞ for counterclockwise_limit. The <DRM Stamp Behaviour> instance has a <DRM LSR 3D Location> component specifying a location at the base of the tree, so that the w axis runs up the centre of the tree.