Introduction
This page is intended as an example of how to define a set of metadata in a way that facilitates inclusion in an X3D scenegraph using the X3D Metadata nodes. Preparing and publishing this documentation of your metadata will allow users to extract and use the metadata included in your X3D content. This page presents as an example a set of metadata that would be applicable to X3D renderings of protein structure such as published in the NIH Print Exchange.
This page documents the http://www.kshell.com/ns/protein3d/v01 Metadata Schema.
The metadata schema is identified by a URI; and in a MetadataSet following this schema the URI is given in the reference field of the MetadataSet node.
When a MetadataSet is at a top-level, not contained as a value inside another MetadataSet, the name field should be regarded as an informal name of the schema.
When a MetadataSet is contained within another MetadataSet governed by a schema, the name of the contained MetadataSet should identify its role in the containing MetadataSet.
Informal schema name : Protein3d
- Name
- The identifier for one item of metadata; entered as the name field of the Metadata node. Must conform to the X3D standard for the SFString type.
- Type
- The X3D type of the metadata element. At X3D v3.3 the following types are defined
- MetadataString
- MetadataBoolean
- MetadataInteger
- MetadataDouble
- MetadataFloat
- MetadataSet
- Cardinality
- Specifies how many items may be contained in the value field of the Metadata node. Follows the notation
minCount:maxCount
- If one and only one item is required, the Cardinality is 1:1
- If an arbitrary number of items is allowed the Cardinality is 0:*
- If the metadata is to be interpreted as a coordinate in 3D space, the Cardinality would be 3:3
- Definition
-
Specifies how the metadata is to be interpreted.
The reference field of a Metadata node may be used to more formally specify how the
value is interpreted by specifying a URI that formally documents that interpretation. Two cases which illustrate this usage are
- A date value can be included in a Metadata scheme as a MetadataString node; and the formatting for dates may be specified by reference to the XML Schema Datatypes published by the W3C; the URL https://www.w3.org/TR/xmlschema-2/#date in the reference field will define the rules for parsing a date from a string value.
- A enumerated type can be included as a MetadataString and a URI in the reference field will identify a resource that gives the allowed enumeration values.
Example conforming to X3D v 3.3
<Group DEF='group_ME_Shape_IndexedTriangleSet'>
<MetadataSet>
<MetadataSet containerField="value" name="Protein3d" reference="https://www.kshell.com/ns/protein3d/v01" >
<MetadataString containerField="value" name='PDB' value='"5RE9"' />
<MetadataString containerField="value" name='DOI' value='"10.2210/pdb5RE9/pdb"' />
</MetadataSet>
</MetadataSet>
<Shape>
<Appearance>
<Material ... />
</Appearance>
<IndexedFaceSet ...>
...
</IndexedFaceSet>
</Shape>
</Group>
Dedicated to the Public Domain by the author with the terms of the Creative Common CC0 dedication. All are welcome to adapt, modify, or extend the material presented and the proposed documentation format.