<xs:attribute name="ypos" type="xs:int"/>
<xs:attribute name="width" type="xs:int"/>
<xs:attribute name="height" type="xs:int"/>
- <xs:attribute name="viewId" type="xs:ID" use="optional"/>
+ <xs:attribute name="viewId" type="xs:string" use="optional">
+ <xs:annotation>
+ <xs:documentation>additional identifier which properly disambiguates
+ the structure view from any other view with the same attributes. This is not an ID,
+ because it is possible to have many references to the same physical structure view
+ from different sequences in an alignment. A structureState element citing the same
+ viewId will appear for each instance.</xs:documentation>
+ </xs:annotation>
+ </xs:attribute>
</xs:extension>