Class

• <DRM World 3x3>

Superclass

• <DRM SEDRIS Abstract Base>

Subclass

• None.

Definition

An instance of this DRM class specifies a nine element matrix containing scaling and rotation data as part of a <DRM World Transformation> instance. The direction of rotation is determined by the right-hand rule.

Translation data is not provided by a <DRM World 3x3> instance, because a <DRM World 3x3> instance only exists as part of a <DRM World Transformation> instance. The translation, or offset, component of a <DRM World Transformation> instance is provided by the mandatory <DRM Location> component of the <DRM World Transformation> instance. In essence, a matrix specified by a <DRM World 3x3>  instance can be considered to be a full transformation matrix in which the rightmost column and bottom row have been omitted, because each is implicitly (0, 0, 0, 1).

<DRM World Transformation> instances usually exist in the scope of a <DRM Environment Root> instance defining a non-LSR SRF. Consequently, <DRM World 3x3> instances usually exist within a world SRF, hence the name.

The matrix multiplication order is defined by:

w = M × v

where:

M is the <DRM World 3x3> matrix,
v is the original location vector, and
w is the resulting location vector.

The world_3x3 field specifies an orientation matrix.

Class diagram

Figure 6.364 — DRM_World_3x3

Constraints

• Publishable Object

Example(s)

• Scale and rotation applied to a <DRM Model> when placing an instance.

• The house near Dixie Road is facing east. The large house across the street is facing west.

• See <DRM Local 4x4> for more examples and explanations of matrix structure.