area (db.area)
area — A region defined for a callout in a graphic or code example.
Synopsis
area (db.area) ::=
alt?
Attributes
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)
- units (enumeration)
- units (enumeration)
Required attributes are shown in bold.
Description
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 C, Interchanging DocBook Documents.)
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 C, Interchanging DocBook Documents.
The coords, which are
required, identify the location of the region. The coordinates are
CDATA; how they are interpreted depends on the
units specified:
calspairThe coordinates are expressed using the semantics of the CALS graphic attributes. The format of the coordinates is “x1,y1 x2,y2”. This identifies a rectangle with the lower-left corner at (x1,y1) and the upper-right corner at (x2,y2). The x and y coordinates are integers in the range 0 to 10000; they express a percentage of the total distance from 0.00 to 100.00%. The lower-left corner is (0,0).
linecolumnThe coordinates are expressed using lines and columns. The format of the coordinates is “line column.” In a graphic context, the meaning of this unit is unspecified.
linerangeThe coordinates are expressed using lines. The format of the coordinates is “startingline endingline.” In a graphic context, the meaning of this unit is unspecified.
linecolumnpairThe coordinates are expressed as a continuous flow of characters. The format of the coordinates is “line1 col1 line2 col2”. This identifies a flow of characters that begins at col1 of line1 and extends to col2 of line2. If line1 and line2 are different, then the region includes all of the intervening lines (including text that occurs before col1 and after col2). In other words, this unit does not specify a rectangle. In a graphic context, the meaning of this unit is unspecified.
otherunitsIf specified, then the
otherunitsattribute is expected to identify the units in some implementation-specific way.
The units attribute is not
required; if it is not specified, the semantics of the coordinates
must be inherited from the surrounding areaspec or
areaset element or implied in some
implementation-specific manner.
In processing systems in which the mark is inserted
automatically, the label
attribute is provided as a mechanism for specifying what the mark
should be.
The author may point to any relevant information with linkends. DocBook does not specify a
semantic for these links. One possible use would be for providing a
link back to the appropriate callout in an online
environment.
Attributes
Common attributes (ID required) and common linking attributes.
- coords
Provides the coordinates of the area. The coordinates must be interpreted using the
unitsspecified.- label
Specifies an identifying number or string that may be used in presentation. The area label might be drawn on top of the figure, for example, at the position indicated by the coords attribute.
- otherunits
Identifies the units used in the
coordsattribute when theunitsattribute is “other” . This attribute is forbidden otherwise.- units
Identifies the units used in the coords attribute. The default units vary according to the type of callout specified:
calspairfor graphics andlinecolumnfor line-oriented elements.Enumerated values: “calspair” Coordinates expressed as a pair of CALS graphic coordinates.
“linecolumn” Coordinates expressed as a line and column.
“linecolumnpair” Coordinates expressed as a pair of lines and columns.
“linerange” Coordinates expressed as a line range.
Children
The following elements occur in area: alt.
See Also
area (db.area.inareaset)