The Digital Lecture BoardSynchronous, Collaborative, Remote Instruction © 1998 University of Mannheim LS Praktische Informatik IV L 15, 16 D-68161 Mannheim |
1. Just type "dlb ip/port" in the dlb directory. The reliable multicast protocol smp is launched automatically with a default port. When finishing the dlb, smp is also automatically killed
2. Type smp& once. Smp runs now in the background and can be reused several times. Then type "dlb -a 0 ip/port" to start the digital lecture board.
You may also want to use the dlb with the MBone session directory sdr. Please copy the sdr2.plugin.S22.whiteboard.udp.dlb.dlb plugin file to the ~/.sdr/plugin directory in your home directory. Make sure your PATH variable contains a path tp the dlb binaries otherwise sdr won't install the plugin. Note: If sdr is installed, the dlb setup tool automatically copies the plugin file to the plugin directory.
If you don't specify a destination address, dlb uses default values. The following further command line options are supported:
-l {0,1}
disable/enable late join (defaults to 1)
-a {0,1} disable/enable
automatic start-up of smp (defaults to 1)
-e {0,1} disable/enable
encryption on startup (defaults to 0)
-p smpport set port number for the connection to
the reliable multicast protocol smp (defaults to 5000)
-t ttl
set time-to-live to ttl (defaults to 16)
dest/port set destination
ip address and destination port (defaults to 224.2.141.55/32460)
Example: dlb -a 0 -p 6789 -t 63 224.2.3.4/50000
In this example, you need smp listening at port number 6789 prior to start the dlb. To start smp with a different port, type:
smp -p 6789
You may also wish to disable the multicast loopback option of smp. To disable multicast loopback, use the -l command line option of smp:
-l {0,1} disable/enable multicast loopback
Click on this button to toggle between on-line and off-line mode. In the
on-line mode, any dlb operation (drawing, creating pages etc.) is transmitted
to the multicast group. In off-line mode, operations are only performed
locally. This provides you with a private workspace. If you toggle back
to on-line mode, the outcome of your private work can be transmitted to
the group. Saving dlb documents includes public and private operations.
Click on this button to enable/disable annotation mode. An annotation can
be any graphical operation except images and page operations. Annotations
are never transmitted to the group. Saving dlb documents includes annotations.
Click on this button to enable/disable a telepointer which is a pointing
device that can be seen by the whole group. The Media menu
provides you with further settings for this mode.
Quick copy mode. Click on an item and drag mouse to copy the item. No select
required.
Quick
delete mode. Click on an item to delete it. No select required.
Insert and edit text item.
Insert freehand line.
Insert poly line. Terminate polyline by double clicking the left mouse
button.
Insert line.
Insert arrow.
Insert horizontal line.
Insert vertical line.
Insert filled rectangle. Hold the shift key pressed while dragging in order
to get a square.
Insert outlined rectangle. Hold the shift key pressed while dragging in
order to get a square.
Insert filled oval. Hold the shift key pressed while dragging in order
to get a circle.
Insert outlined oval. Hold the shift key pressed while dragging in order
to get a circle.
Insert a point (small filled circle).
Insert filled polygon. Terminate polygon by double clicking the left mouse
button.
Insert outlined polygon. Terminate polygon by double clicking the left
mouse button.
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The page selector provides you with access to private and public pages by either clicking on the pages or by using the arrow buttons to browse through the pages. Pages of remote sites are marked with the canonical name (cname) behind. Page names can be changed by double clicking on the name. The most left button creates new blank pages. Furthermore, the page selector gives you access to the different usage modes of the dlb as described above. If you are working in the off-line mode (see left screen shot), private pages are created in a separate listbox below the listbox with the public (global) pages. When switching back to on-line mode, private pages can be transmitted to the group by clicking on the pages. The page selector can be hidden using the View menu. |
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The page info field below the drawing area displays information about the current page and zoom factor. The arrow buttons allow to change pages locally. The middle button switches back to the current global page. |
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The participant info displays a list of all participants currently joining the session. The information is based on RTCP protocol information. Clicking on single participants brings you more information. The data of the local participant can be modified. The participant information can be hidden by using the View menu. |
File
|
Open ...
Save Save As ... Open Pages ... Save Pages Open Selection ... Save Selection ... Exit |
Open an existing dlb document
Save current dlb document Save dlb document using a different name Open dlb pages Save selected pages Open a dlb selection Save selected items Exit dlb |
Edit
|
Undo
Cut Paste Copy Delete Select All New Page Clear Page Group Ungroup |
Undo last operation
Cut selected items to the clipboard Paste items from the clipboard Copy selected items to the clipboard Delete selected items Select all items on current page Create a new blank page Clear current page Group selected items Ungroup selected items |
View
|
Image Orientation
Image Lock Use PS direct Zoom Show Snap Smooth Lines |
Change orientation of images and postscript slides
Freeze position of images/postscript slides (useful when annotating) Enable/disable direct postscript display when loading dlb documents which contain postscript Change the zoom factor of the complete document Show/Hide certain control panels and options Enable/disable snap to grid Enable/disable freehand line smoothing |
Insert
|
Image ...
Text ... Window ... PS direct ... |
Insert image (gif, pcx, ps, eps and many more)
Insert ascii text Insert the contents of an X window into the shared workspace of the dlb Insert Postscript (uses gs for direct display into the shared workspace, faster than Image ...) |
Media
|
Telepointer ...
Voting ... Online Feedback ... Chat ... |
Insert/Change Telepointer
Raise/Enable/Configure Voting facility Raise/Enable/Configure Online Feedback facility Raise/Enable/Configure Chat Window |
Options
|
Middle Mouse
Right Mouse Draw Width Draw Color Background Color Font Type Font Size Font Style Security ... Snap ... Save ... Save Settings |
Configure middle mouse button
Configure right mouse button (uses per default a quick access menu) Change draw width Change draw color Change background color of current and future pages Change font type Change font size Change font style Set security options (enable/disable, user-profile, customize security, passphrase etc.) Change Snap settings (grid and snap values) Change save settings (currently only a renaming of pages is supported) Save current dlb settings |
Help | About ...
Usage ... |
Display author and copyright information
Display this user guide by calling a web browser |
© 1998 Werner Geyer, geyer@pi4.informatik.uni-mannheim.de