Class Name: Property Set

Superclass - <SEDRIS Abstract Base>

Subclasses

Definition

An instance of this DRM class groups together a set of instances of classes that

1. have formal component relationships with <Geometry Representation> and / or <Feature Representation>, and
2. that specify either 'attributes', such as <Rendering Priority Level>, or metadata.

A <Property Set> instance provides a mechanism for a set of 'attributes' to be explicitly reused by many <Geometry Representation> and / or <Feature Representation> instances.

Primary Page in DRM Diagram:

• 19

Secondary Pages in DRM Diagram:

• 6

Example

1. A number of <Polygon> instances that are all coloured red and rendered using flat shading each contain the same <Property Set Index>, which references a <Property Set> containing a <Colour> instance specifying red and a <Rendering Properties> instance specifying flat shading.

2. A number of <Polygon> instances that are all coloured green, have grass texture that is modulated and have an EAC_SURFACE_MATERIAL_TYPE specifying EEC_SRF_MATTY_GRASS. A common <Property Set Index> specifies a <Property Set> containing:

   1. a <Colour> instance specifying green,

   2. an <Image Mapping Function> instance specifying image_mapping_method = SE_IMG_MAPNG_METH_MODULATE, and

   3. a <Property Value> instance specifying an EAC_SURFACE_MATERIAL_TYPE value of EEC_SRF_MATTY_GRASS.

3. A number of <Polygon> instances that all have the same electromagnetic properties and are coloured grey. A common <Property Set> would contain a <Colour> instance specifying grey and a <Property Table Reference> into a <Property Table> of electromagnetic properties.

4. A <Feature Representation> is associated with a <Geometry Representation> that has been developed from it. Both reference the same <Property Set>, which contains a <Colour> instance, <Image Mapping Function> and <Browse Media>. The <Geometry Representation> would use the <Colour> and <Image Mapping Function> but ignore the <Browse Media>.

5. Consider a <Feature Representation> instance with a <Data Quality> component, the fictional field of which is set to SE_TRUE. This particular <Feature Representation> instance also has a <Property Set Index> component, referencing a <Property Set> containing a <Data Quality> instance, the fictional field of which is set to SE_FALSE. Since a <Feature Representation> may contain at most one <Data Quality> instance, the <Data Quality> instance with fictional set to SE_TRUE would be used, as it is contained directly by the <Feature Representation> instance.

6. Consider a <Geometry Representation> instance with two <Property Table Reference> components, which references a <Property Set> that contains another three <Property Table Reference> instances, where all five have distinct meanings. As a <Geometry Representation> may contain many <Property Table Reference> instances, all five will be used by the <Geometry Representation> as required. The two that are contained directly will be used first, then the three that are contained in the <Property Set>.

7. Consider a <Polygon> instance with two <Image Mapping Function> components, which references a <Property Set> that contains another two. As a <Primitive Geometry> may contain many ordered <Image Mapping Function> instances, all four will be used by the <Polygon> as required. The two that are contained directly will be used in order first, then the three that are contained in the <Property Set>, again in order.

8. A <Union Of Primitive Geometry> contains two <Property Table Reference> instances and references two <Property Set> instances. The first <Property Set> contains another <Property Table Reference> and and the second <Property Set> contains another three <Property Table Reference> instances. As an <Aggregate Geometry> may contain many <Property Table Reference> instances, all six would be used by the <Union Of Primitive Geometry> as required. The two that are contained directly would be used first, then the one that is contained in the first <Property Set> and finally the three that are contained in the second <Property Set>.

FAQs

Where can users find more information on 'attribute' objects?

See Part 4, Volume 9 Attribute Inheritance and Context Technical Guide of the SEDRIS Documentation Set for further information.

What is the order of precedence for 'attribute' objects within a single <Property Set> instance?

See the constraint <<Precedence of Property Set Index>>.

What if a <Geometry Representation> or <Feature Representation> instance has more than one <Property Set Index> component, where the referenced <Property Set> instances have conflicting attribute objects?

See the constraint <<Precedence of Property Set Index>>.

What if a <Property Set> instance contains attribute objects that are related to <Feature Representation> but is referenced by a <Geometry Representation> instance? Or vice versa?

See the constraint <<Property Set Components>>.

Constraints

• <<Publishable Object>>
• <<No Attribute Conflicts>>
• <<Property Set Components>>

Composed of (two-way)

• zero or one <Classification Data> instance
• zero or more <Colour> instances
• zero or more {ordered} <Image Mapping Function> instances
• zero or one <Light Rendering Properties> instance
• zero or one <Presentation Domain> instance
• zero or more <Property Table> instances
• zero or more <Property Table Reference> instances
• zero or more <Property Value> instances
• zero or one <Rendering Priority Level> instance
• zero or one <Rendering Properties> instance
• zero or one <Spatial Extent> instance

Composed of (two-way metadata)

• zero or one <Access> instance
• zero or one <Citation> instance
• zero or more <Cross Reference> instances
• zero or one <Data Quality> instance
• zero or one <Description> instance
• zero or one <Time Constraints Data> instance

Component of (two-way)

• one <Property Set Table> instance

Inherited Field Elements