|
Property
|
Description
|
|
Class
|
- <DRM Geometry Model Instance>
|
|
Superclass
|
|
|
Subclass
|
|
|
Definition
|
An instance of this DRM class specifies a single case of the existence
of a <DRM Geometry Model> within a given
transmittal, including variations or specialization unique to that case.
In particular, a
<DRM Geometry Model Instance> is used to
transform a <DRM Geometry Model> into the
spatial reference frame of another
<DRM Geometry Model> or that of an
<DRM Environment Root>.
|
|
Class diagram
|
Figure 6.113 —
DRM_Geometry_Model_Instance
|
|
Inherited field elements
|
|
Field name
|
Range
|
Field data type
|
None |
|
|
|
|
Field elements
|
|
Field name
|
Range
|
Field data type
|
None |
|
|
|
Associated to (one-way) (inherited) |
|
Associated to (one-way) |
|
Associated by (one-way) (inherited) |
|
Associated by (one-way) |
|
Associated with (two-way) (inherited) |
|
Associated with (two-way) |
|
Composed of (two-way) (inherited) |
|
Composed of (two-way) |
|
Composed of (two-way metadata) (inherited) |
|
Composed of (two-way metadata) |
|
Component of (two-way) (inherited) |
- zero or more <DRM Alternate Hierarchy Related Geometry> instances, each with a <DRM Hierarchy Data> link object
- zero or more <DRM Animation Related Geometry> instances
- zero or more <DRM Classification Related Geometry> instances, each with a <DRM Classification Data> link object
- zero or one <DRM Environment Root> instance
- zero or one <DRM Geometry Model> instance
- zero or more <DRM Level Of Detail Related Geometry> instances, each with a <DRM Base Level Of Detail Data> link object
- zero or more <DRM Octant Related Geometry> instances, each with a <DRM Octant Data> link object
- zero or more <DRM Perimeter Related Geometry> instances, each with a <DRM Perimeter Data> link object
- zero or more <DRM Quadrant Related Geometry> instances, each with a <DRM Quadrant Data> link object
- zero or more <DRM Separating Plane Relations> instances, each with a <DRM Separating Plane Data> link object
- zero or more <DRM Spatial Index Related Geometry> instances, each with a <DRM Spatial Index Data> link object
- zero or more <DRM State Related Geometry> instances, each with a <DRM State Data> link object
- zero or more <DRM Time Related Geometry> instances, each with a <DRM Time Constraints Data> link object
- zero or more <DRM Union Of Geometry Hierarchy> instances
|
Component of (two-way) |
|
|
Constraints
|
|
|
Clarifications
|
1
An association between a
<DRM Geometry Hierarchy> instance
and a <DRM Feature> instance indicates that
the <DRM Geometry Hierarchy>
and the <DRM Feature> are
alternate representations of the same
environmental object.
2
An association between two
<DRM Geometry Hierarchy> instances
indicates that they are alternate representations of the same
environmental object.
3
An association from a
<DRM Hierarchy Summary Item>
instance to a <DRM Geometry Hierarchy>
indicates that the
<DRM Hierarchy Summary Item>
summarizes that <DRM Geometry Hierarchy>.
4
An association from a
<DRM Reference Surface> instance to a
<DRM Geometry Hierarchy> indicates
that the <DRM Geometry Hierarchy>
organizes the geometric objects that specify the resolution
surface of the <DRM Reference Surface>.
5
An association from a
<DRM Geometry Model Instance>
instance to a <DRM Geometry Model>
indicates that the
<DRM Geometry Model Instance>
instances that particular
<DRM Geometry Model>.
6
This allows a
<DRM Geometry Model Instance>
to be conformal. If
present, the <DRM Conformal Behaviour>
component is applied after
any <DRM Transformation> that is present.
7
This positions and orients the
given <DRM Geometry Model Instance>
in the target spatial reference frame.
|
|
Example(s)
|
Consider a <DRM Model> of a building, consisting of a
<DRM Geometry Model> describing its geometric
representation, where the <DRM Model> is described in
an LSR 3D spatial reference frame.
To instance this <DRM Model> into an
<DRM Environment Root>, the
spatial reference frame of which is 3D geodetic,
the data provider constructs a
<DRM Geometry Model Instance>
with a <DRM World Transformation> component,
and incorporates it into the <DRM Geometry
Hierarchy> of that <DRM Environment Root>.
The <DRM World Transformation> specifies the
<DRM CD 3D Location> at which the
<DRM Model>'s 0, 0, 0 coordinate will be instanced,
together with any other transformation information required to orient
and scale the <DRM Model> properly.
Consider a <DRM Geometry Model> describing
the rotor of a helicopter, and intended for use within a larger
<DRM Geometry Model> of the entire helicopter.
Both are defined in 3D LSR spatial reference frames.
The helicopter model will contain a
<DRM Geometry Model Instance>
of the rotor model, with an <DRM LSR
Transformation> component containing a <DRM Rotation>
instance with a <DRM Rotation Control Link>.
The <DRM LSR Transformation> specifies both
the transformation required to position the rotor within the helicopter
model, and the <DRM Variable> within the larger
helicopter <DRM Model> that will be plugged into the
rotor <DRM Model>'s internal <DRM
Variable> for angle of rotation.
|