IDirect3DRMAnimation and IDirect3DRMAnimationSet Interfaces

An animation in Retained Mode is defined by a set of keys. A key is a time value associated with a scaling operation, an orientation, or a position. A Direct3DRMAnimation object defines how a transformation is modified according to the time value. The animation can be set to operate on a Direct3DRMFrame object, so it could be used to animate the position, orientation, and scaling of Direct3DRMVisual, Direct3DRMLight, and Direct3DRMViewport objects.

The IDirect3DRMAnimation::AddPositionKey, IDirect3DRMAnimation::AddRotateKey, and IDirect3DRMAnimation::AddScaleKey methods each specify a time value whose units are arbitrary. If an application adds a position key with a time value of 99, for example, a new position key with a time value of 49 would occur exactly halfway between the (zero-based) beginning of the animation and the first position key.

The animation is driven by calling the IDirect3DRMAnimation::SetTime method. This sets the visual object's transformation to the interpolated position, orientation, and scale of the nearby keys in the animation. As with the methods that add animation keys, the time value for IDirect3DRMAnimation::SetTime is an arbitrary value, based on the positions of keys the application has already added.

A Direct3DRMAnimationSet object allows Direct3DRMAnimation objects to be grouped together. This allows all the animations in an animation set to share the same time parameter, simplifying the playback of complex articulated animation sequences. An application can add an animation to an animation set by using the IDirect3DRMAnimationSet::AddAnimation method, and it can remove one by using the IDirect3DRMAnimationSet::DeleteAnimation method. Animation sets are driven by calling the IDirect3DRMAnimationSet::SetTime method.

For related information, see the IDirect3DRMAnimation and IDirect3DRMAnimationSet interfaces.