.\" $Xorg: StripChart,v 1.3 2000/08/17 19:42:28 cpqbld Exp $
.NH 2
StripChart Widget
.XS
StripChart Widget
.XE
.IN "StripChart widget" "" "@DEF@"
.Ds 0
.TA 2.0i
.ta 2.0i
.sp
Application Header file <Xaw/StripChart.h>
.IN "StripChart.h" ""
Class Header file <Xaw/StripCharP.h>
.IN "StripCharP.h" ""
Class stripChartWidgetClass
.IN "stripChartWidgetClass" ""
Class Name StripChart
.IN "StripChart widget" "class name"
Superclass Simple
.sp
.De
.LP
The StripChart widget is used to provide a roughly real
time graphical chart of a single value. For example,
it is used by the common client program \fBxload\fP
to provide a graph of processor load. The StripChart
reads data from an application, and updates the chart
at the \fBupdate\fP interval specified.
.NH 3
Resources
.LP
When creating a StripChart widget instance, the following resources are
retrieved from the argument list or from the resource database:
.LP
.IN "StripChart widget" "resources"
.TS H
expand;
lw(1i) lw(1i) lw(1i) lw(.5i) lw(2i).
_
.sp 3p
.TB
Name Class Type Notes Default Value
.sp 3p
_
.TH
.R
.sp 3p
accelerators Accelerators AcceleratorTable NULL
ancestorSensitive AncestorSensitive Boolean D True
background Background Pixel XtDefaultBackground
backgroundPixmap Pixmap Pixmap XtUnspecifiedPixmap
borderColor BorderColor Pixel XtDefaultForeground
borderPixmap Pixmap Pixmap XtUnspecifiedPixmap
borderWidth BorderWidth Dimension 1
colormap Colormap Colormap Parent's Colormap
cursor Cursor Cursor None
cursorName Cursor String NULL
depth Depth int C Parent's Depth
destroyCallback Callback XtCallbackList NULL
foreground Foreground Pixel XtDefaultForeground
getValue Callback XtCallbackList NULL
height Height Dimension 120
highlight Foreground Pixel XtDefaultForeground
insensitiveBorder Insensitive Pixmap GreyPixmap
international International Boolean C False
jumpScroll JumpScroll int A half the width of the widget
mappedWhenManaged MappedWhenManaged Boolean True
minScale Scale int 1
pointerColor Foreground Pixel XtDefaultForeground
pointerColorBackground Background Pixel XtDefaultBackground
screen Screen Pointer R Parent's Screen
sensitive Sensitive Boolean True
translations Translations TranslationTable NULL
update Interval int 10
width Width Dimension 120
x Position Position 0
y Position Position 0
.sp 3p
_
.TE
.Ac
.As
.Bg
.Gp
.Bc
.Bp
.Bw
.Cm
.Cu
.Cn
.Dp
.Dc
.IP \fBforeground\fP 1.5i
A pixel value which indexes the widget's colormap to derive the color
that will be used to draw the graph.
.IP \fBgetValue\fP 1.5i
A list of callback functions to call every \fBupdate\fP seconds.
This list should contain one function, which returns the
value to be graphed by the StripChart widget. The following
section describes the procedural interface. Behavior when this list has
more than one function is undefined.
.Hw
.IP \fBhighlight\fP 1.5i
A pixel value which indexes the widget's colormap to derive the color
that will be used to draw the scale lines on the graph.
.Ib
.Ix
.IP \fBjumpScroll\fP 1.5i
When the graph reaches the right edge of the window it must be
scrolled to the left. This resource specifies the number of pixels
it will jump. Smooth scrolling can be achieved by setting this resource
to 1.
.Mm
.IP \fBminScale\fP 1.5i
The minimum scale for the graph. The number of divisions on the graph
will always be greater than or equal to this value.
.Pf
.Pb
.Sc
.Se
.Tr
.IP \fBupdate\fP
The number of seconds between graph updates. Each update is
represented on the graph as a 1 pixel wide line. Every \fBupdate\fP seconds
the \fBgetValue\fP procedure will be used to get a new graph point,
and this point will be added to the right end of the StripChart.
.Xy
.NH 3
Getting the StripChart Value
.IN "StripChart widget" "getting the value"
.LP
The StripChart widget will call the application routine passed to it
as the \fBgetValue\fP callback function every \fBupdate\fP seconds to
obtain another point for the StripChart graph.
.LP
The calling interface for the \fBgetValue\fP callback is:
.IN "StripChart widget" "getValue callback" "@DEF@"
.FD 0
void (*\fIgetValueProc\fP)(\fIw\fP, \fIclient_data\fP, \fIvalue\fP)
.br
Widget \fIw\fP;
.br
XtPointer \fIclient_data\fP;
.br
XtPointer \fIvalue\fP; /* double * */
.FN
.IP \fIw\fP 1i
Specifies the StripChart widget.
.IP \fIclient_data\fP 1i
Specifies the client data.
.IP \fIvalue\fP 1i
Returns a pointer to a double. The application should set the address
pointed to by this argument to a double containing the value to be
graphed on the StripChart.
.LP
This function is used by the StripChart to call an application routine.
The routine will pass the value to be graphed back to the the StripChart
in the \fBvalue\fP field of this routine.