Description:
Dataimage.cgi
reads an image definition from
/var/lib/remstats/datapage/imagename.image
. Some of the commands are in common
with datapage.cgi and are documented
there:
oid, rrd, status, eval, debug, macro, macroend and *EOD*
These retrieve and manipulate data. There are also commands to create
images:
image, colordef, color, linewidth, line, rectangle, circle,
fill, font, text, out, flow
image
The image command has two formats. The first looks like:
image WIDTH HEIGHT
This creates a blank image of the size specified. Sometimes you'll want a
background for the image, and you can use the second form to specify
a file to read for the background:
image BGFILE
This will create the new image the same size as the one in BGFILE
,
by reading BGFILE
and using its contents as the background. N.B., the
image must be a PNG graphic.
The image
command also defines a few colors (see colordef
below):
black
, white
and transparent
, sets the current color to
black
, fills the image with white
and sets the linewidth
to 1.
colordef
[It can also be spelled colourdef
.]
This defines a new colour and names it. The command looks like:
colordef COLORNAME RED GREEN BLUE
where RED
, GREEN
and BLUE
specify the level of each of those colours
to be mixed to define the colour referred to in the script as COLORNAME
.
rectangle
This is a way to draw a rectangle, without useing line
4 times:
rectangle X1 Y1 X2 Y2 [filled]
The co-ordinates (X1
, Y1
) and (X2
, Y2
) define oposite corners
of the rectangle. If the keyword filled
is added to the end, the
rectangle will be filled with the current colour as well.
flow
This draws a strange double-headed, bi-coloured arrow. Think of it as two
half arrows, split lengthwise, one in each direction. The colour and width
of each half arrow indicates the flow in that direction. I use it for
indicating network traffic flow, which usually isn't the same in both
directions. It looks like:
flow X1 Y1 X2 Y2 INFLOW OUTFLOW
The co-ordinates (X1
, Y1
), (X2
, Y2
) indicate the ends of the
flow. INFLOW
and OUTFLOW
indicate the level in each direction,
relative to (X1
, Y1
).
[