| Allegro CL version 8.2 This page is new in 8.2. |
Arguments: chart-axis
Returns the marker-lines
property of a chart-axis
object, which is associated with a chart-widget
or plot-widget
control. The value may be set at
creation time by passing the :marker-lines initarg
to make-instance, or any time
later by calling (setf marker-lines).
Marker lines are straight line segments or thicker bands that are drawn perpendicular to a chart axis. Each line or band is drawn outward from a specified value (for a line) or range of values (for a band) along the axis, to highlight an arbitrary set of values.
An example would be a chart of economic statistics, where the item-axis represents time and has bands extending from it to mark where recessions have occurred in the past.
There are no entries in the chart legend for marker-lines. Their meaning could be noted in the subtitle or footnote text of a chart.
The value of the property should be a list of lists, where each sublist is a property list that describes one line or band to draw perpendicular to the axis. Here are the valid keys for each property list, and the type of value to specify for each one:
:value
: every sublist should have
a :value
entry that specifies the point along the
axis at which to draw a line or band. The value should be a real
number (either an integer or not).
:value-to
: if there is
a :value-to
entry, then a band will be drawn
between the :value
value to
the :value-to
value. Otherwise a line will be drawn
at the :value
value. The value should be a real
number (either an integer or not).
:color
: this is the color in which to draw
the line or band. The value should be an RGB object
(see make-rgb) or a symbol
whose value is an RGB. When unspecified, the color will default to
red
for lines and
light-gray
for bands.
:line-width
: this is the thickness (measured
in pixels) with which to draw the line, when
no :value-to
is specified for a band. The value
should be a positive integer. When unspecified, it defaults to 1.
:line-dashing
: this is the dashing style
with which to draw the line, when no :value-to
is
specified for a band. The value should be one of the keyword symbols
that are valid values for the line-dashing property of a stream, such as
:solid
or :dash
. When
unspecified, it defaults to :solid
.
Here is a sample value of the marker-lines property of an axis that would draw two lines and two bands:
((:value 3.5 :color blue :line-width 5 :line-dashing :dot) (:value 6) (:value 7 :value-to 8.5) (:value 10.4 :value-to 15 :color cyan))
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page is new in the 8.2 release.
Created 2016.6.21.
| Allegro CL version 8.2 This page is new in 8.2. |