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Property
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Description
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Class
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- <DRM Distance Level Of Detail Data>
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Superclass
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Subclass
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Definition
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An instance of this DRM class specifies a level of detail
described in terms of distance from the eyepoint to the
centre of the object.
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Class diagram
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Figure 6.67 —
DRM_Distance_Level_Of_Detail_Data
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Inherited field elements
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Field name
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Range
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Field data type
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None |
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Field elements
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Associated to (one-way) (inherited) |
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Associated to (one-way) |
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Associated by (one-way) (inherited) |
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Associated by (one-way) |
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Associated with (two-way) (inherited) |
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Associated with (two-way) |
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Composed of (two-way) (inherited) |
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Composed of (two-way) |
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Composed of (two-way metadata) (inherited) |
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Composed of (two-way metadata) |
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Component of (two-way) (inherited) |
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Component of (two-way) |
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Constraints
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Clarifications
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1
This is in metres.
2
This is expressed in metres (not percent). This fade band shall
go in the negative direction from the minimum range.
3
This is in metres;
SE_POSITIVE_INFINITY
is a legal range value.
4
This is expressed in metres (not percent). This fade band shall
go in the negative direction from the maximum range.
5
This is the centre point for the LOD test.
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Example(s)
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Consider a <DRM
Level Of Detail Related Geometry> instance which has two
branches, each having an attached
<DRM Distance Level Of Detail Data>.
The first <DRM
Distance Level Of Detail Data> instance has:
The second <DRM
Distance Level Of Detail Data> instance has:
If the eyepoint is moving outward and the distance reaches 90, the first
branch starts fading in. At a distance of 100, the first branch has totally
faded in. At a distance of 180 the first branch starts to fade out.
At a distance of 190 the second branch starts fading in. The first
and second branches are both seen (super-imposed) between the ranges of
190 and 200. At a distance of 200 the first branch is totally faded out,
while the second branch is the only branch seen. At a distance of 990,
the second branch starts fading out, and at 1000 it is completely faded
out.
Consider a <DRM
Level of Detail Related Geometry> instance which has two
branches, each having an attached
<DRM Distance Level Of Detail Data>.
The first <DRM
Distance Level Of Detail Data> instance has:
The second <DRM
Distance Level Of Detail Data> instance has:
If the eyepoint is moving outward and the distance reaches 30, the first
branch starts fading in. At a distance of 50, the first branch
has totally faded in. At a distance of 70 the first branch starts
to fade out. At a distance of 95 the second branch starts fading in.
The first and second branches are both seen (super-imposed) between
the ranges of 95 and 100. At a distance of 100, the first branch is
totally faded out, while the second branch is the only branch seen,
but hasn't completely faded in. At a distance of 110 the second branch
has completely faded in. At a distance of 490 the second branch starts
fading out, and at 500 is completely faded out.
A set of polygonal data is produced with low detail for viewing at
ranges greater than 3200 metres, and organized as a
<DRM Union Of Primitive Geometry>,
with a <DRM
Distance Level Of Detail Data> component specifying this viewing range
so that the intended viewing distance at which these
<DRM Polygon> instances are to be used is provided.
See <DRM
Level Of Detail Related Geometry>'s examples.
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