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skycat fileName -option value ...An argument not starting with "-" is taken to be a FITS image file to load. A "-" by itself means: read the FITS file from the standard input. A file with the suffix ".hfits" is taken to be an H-compressed FITS file and is decompressed automatically. A ".gfits" or ".gzfits" suffix indicates that the FITS file is GZIP compressed and a suffix of ".cfits" is assumed to be UNIX compressed. Image formats other than FITS are not currently supported, but will be in a future release.
The following options are supported:
-file FITSfile | Specify a FITS file to load. The '-file' part is optional, so you can also simply specify a file name, as described above. |
-cat bool | If bool is 1, include 'Data-Servers' menu in the menubar (This is the default). The 'Data-Servers' menu gives you access to the ESO/Archive extensions for browsing astronomical catalogs, plotting objects in the image window and getting images over the network from the image servers, such as the Digitized Sky server. |
-rtd bool | If bool is 1, include the Real-Time menu in the menubar (default is 0). The Real-Time menu gives you access to the VLT Real-Time Display features, such as camera control and rapid frames. To use these features, the rtdServer daemon must be running on the local host. A client application, linked with the Rtd image event library can then send images via shared memory to be displayed in rapid succession. |
-port portnum | Specify a port number to ue for the remote socket interface. The default is 0, which means choose an unused port. See the RTD User's Guide for a description of the remote socket interface. |
-disp_image_icon bool | If bool is 1 (default), display a miniature version of the image in the tool's icon window. |
-default_cmap cmap | Specify the default colormap. This should be one of the names listed in the 'Colors' popup window (default is 'real'). |
-default_itt itt | Specify the default intensity transfer table. This should be one of the names listed in the 'Colors' popup window (default is 'ramp'). |
-colorramp_height pixels | This option can be used to change the height of color bar (the widget at the bottom of the screen displaying the image colors). |
-with_colorramp bool | If bool is true, display the color bar (default). |
-with_zoom_window bool | If bool is true, display the zoom window (default). |
-with_pan_window bool | If bool is true, display the pan window (default). |
-dozoom bool | If bool is true, turn the zoom window on automatically (default). |
-debug bool | If bool is true (default: false) turn on debugging features. This also enables the real-time simulation (when the -rtd option was specified). |
-verbose bool | If bool is true (default: false) display debugging messages at run-time (for debugging). |
-display dpy | Specify the X server to use. |
Arguments which are not switches are interpreted as image files.
To include your own catalog in skycat, you have to implement a catalog server, and add an entry to the skycat config file for it.
Note that there has been some discussion about standards for catalog servers and the URL syntax used to access them. Please see Astronomical Server URL for more information on that.
A catalog server is called via HTTP as a cgi-bin application. The syntax for the URL is taken from the skycat config file. The URL contains the query parameters, such as RA, DEC, RADIUS, etc. The format of the return value is a tab separated table with column headings separated from data by a dashed line "---".
skycat expects the first three columns to always be: ID, RA and DEC. The following columns can be anything. RA and DEC should be in degrees, J2000. In the the query arguments, RA and DEC are specified in HH:MM:SS.sss format and the radius in arcmin.
The MORE URL should point to an HTML page with more information on the object. skycat passes the URL to netscape for display.
The PREVIEW URL should point to either a FITS image (possibly compressed) of the selected object or a tab table with data to plot as an X,Y graph. The Content-type of the HTTP result is used to determine whether the data is a FITS image or a tab table and whether or not it is compressed. The Astronomical Server URL document mentioned above describes the allowed Mime-type/Content-type values. These have been implemented in skycat.
If the Content-type of the PREVIEW data returned from an HTTP server is recognized as a tab table (text/x-starbase, etc., or even text/plain), it it should be an ASCII tab table with 2 columns. The first column is plotted as X and the second as Y and the column headings are displayed as the X and Y graph labels.
skycat/interp/library/Skycat.tcl
)
rtd/rtdrmt
module for examples)
shm
" subcommand)
get_catalog_info
{}
display_image
{ra dec width height {equinox 2000}
}
mark_image
{ra dec width height
}
unmark_image
{id
}
load_image
{filename
}
pick_object
{{cmd ""}
} See also the comments at end of source file: cat/tclcat/library/SkyCat.tcl. The PickObject interface is (or will be) described in the man page RtdImagePick(n).
Basically, what you can do is open a socket
connection and send ASCII strings to Skycat (since it is based on the
RTD). The port number can be specified on the Skycat command line with the
-port
num option.
The strings are interpreted as RTD subcommands. The command method is called with the given arguments and the result is returned via socket again. It is similar to Tk send, except that it is more secure (you can only access RTD subcommands) and can easily be used by a C application (or any other language).
The format to send a command is:
command
is one of the
RTD subcommands (without an instance name). The result read from the
socket has the format:
Check out RTD User's Guide and the rtd/rtdrmt directory in the Skycat source tree for examples of how to use the remote interface.
-shm_header 1
and -shm_data 1
options
when starting skycat, so that shared memory is used automatically.
shm
" (also available
via the remote socket interface) to tell skycat to use shared memory
and to get the shared memory ids.
See the RTD User's Guide for a description of the rtdimage subcommands.
Please send questions or comments to
abrighto@eso.org.
Last modified: Thu Aug 6 20:37:07 MEST 1998
Copyright © 1996 ESO - European Southern Observatory