area — A region defined for a callout in a graphic or code example


area (db.area) ::= alt?

Attribute synopsis

Common attributes (ID required) and common linking attributes.

Additional attributes:

  • coords

  • label

  • Exactly one of:

    • units (enumeration) = “calspair” | “linecolumn” | “linecolumnpair” | “linerange

    • Each of:

      • units (enumeration) = “other”

      • otherunits (NMTOKEN)

Required attributes are shown in bold.


An area is an empty element holding information about a region in a graphic, program listing, or screen.

The region is generally decorated with a number, symbol, or other distinctive mark. The mark is usually used as the label for the callout in a calloutlist, which allows the reader to identify which callouts are associated with which regions. The marks may be generated by the processing application from the areas, or it may be added by some other process. (This is an interchange issue. See Appendix D.)

For a complete description of callouts, see callout.

Processing expectations

Suppressed. This element provides data for processing but it is not expected to be rendered directly.

The processing expectations of callouts are likely to deserve special consideration for interchange. See Appendix D.

The coords, which are required, identify the location of the region. The coordinates are CDATA; how they are interpreted depends on the units specified:


The coordinates are expressed using the semantics of the CALS graphic attributes. The format of the coordinates is “x1,y1 x2,y2”. ...

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