For signalling charts styles can contain any of the attributes listed in Signalling Chart Attributes and Styles. Styles are explained more in Defining Styles.
There is a built-in default style for each signalling chart
element: arrow
, box
, emptybox
, divider
,
blockarrow
, pipe
entity
, entitygroup
,
symbol
, indicator
54, title
, subtitle
, note
,
comment
, endnote
, vertical
55, vertical_brace
,
vertical_bracket
, vertical_range
, vertical_pointer
,
symbol
56 and
text
57.
There are also predefined styles for grouped entities and boxes
for when they are collapsed: entitygroup_collapsed
,
box_collapsed
and box_collapsed_arrow
, the latter is used when a
box is collapsed to a bidirectional arrow. Attributes of large entitygroups default
to the entitygroup_large
style.
The following refinement styles are defined further governing the appearance of elements
vertical->
, vertical>
, vertical>>
, vertical=>
,
vertical--
, vertical++
, vertical..
and vertical==
.
Redefining refinement styles enables you to quickly define, e.g., various arrow styles and use the various symbols as shorthand for these. Usually style names containing non-letter characters have to be quoted, but for the above styles the parser is expected to recognize them without quotation. So both below are valid.
Finally there are two more pre-defined styles for signalling charts: strong
and weak
.
By adding these to any element you will get a more and less emphasized look,
respectively. The benefit of these compared to making elements stronger or
weaker by yourself is that they are defined in all chart designs
in a visually appropriate manner. Thus you do not need to change anything
when changing chart design just keep using them unaltered.
As a related comment we note that chart designs modify all the above styles and the
default value for the hscale
, compress
, vspacing
, numbering
,
indicator
, angle
and text
chart options, too.
Thus, in summary the actual attributes of an element are set using the following logic.
=>
to make an arrow double-lined.)
text.*
, compress
, vspace
, indicator
, numbering
,
auto_heading
and angle
. In order for these chart options to be effective
default styles usually have no value specified for these attributes. You can set
these attributes in styles, e.g., to set font type for empty boxes,
which will take precedence over chart options.
The style indicator
determines
the appearance of the small symbols that indicate elements hidden due to a
collapsed box or entity group.
referring to vertical boxes and block arrows
referring to all symbols
referring to text at
commands
‘arrow_self’ is applied to arrows starting and ending at the same entity after and in addition to style ‘arrow’. The others are applied (potentially after ‘arrow_style’ to line segments, also for bi-directional arrows. Thus there is no separate ‘<->’ style, for example.
If you specify the attribute several times, the last one is used.