Open Mash Cross Reference
mash/tcl/cues/send-cues.tcl

   # send-cues.tcl --
   #
   #       An object for sending cues in a collaborative meeting.
   #
   # Copyright (c) 1998-2002 The Regents of the University of California.
   # All rights reserved.
   #
   # Redistribution and use in source and binary forms, with or without
   # modification, are permitted provided that the following conditions are met:
  #
  # A. Redistributions of source code must retain the above copyright notice,
  #    this list of conditions and the following disclaimer.
  # B. Redistributions in binary form must reproduce the above copyright notice,
  #    this list of conditions and the following disclaimer in the documentation
  #    and/or other materials provided with the distribution.
  # C. Neither the names of the copyright holders nor the names of its
  #    contributors may be used to endorse or promote products derived from this
  #    software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
  # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #
  # An object for sending cues in a collaborative meeting.
  # The cues currently available are "raise hand", "speak
  # louder", "agree", and "disagree". The idea is for a
  # person to express these cues in a non-verbal manner.
  #
  # This class makes a gui for the cues; there is just
  # one format now. It is a list of checkbuttons with the
  # cues images next to them.
  #
  # It also sends the cues messages on the global
  # coordination bus. The client of this class needs to
  # pass in this bus object.
  #
  # See also: CuesReceiver
  #
  # Examples of usage can be found in vic.
  #
  
  import CheckButton
  
  Class CuesSender
  
  #
  # Initialize the global coordination bus so the client
  # can use this class. The client should use CoordBus_
  # and the associated CBChannel/Site object. See the
  # creation of buses in application-{vic,vat}.tcl for
  # an example
  #
  CuesSender proc set_cb { cb } {
          # initialize global coordination bus
          CuesSender set glob_chan_ $cb
  }
  
  #
  # Create a CuesSender object and the gui
  # path: the gui is constructed using this path, the
  #       client should pass in the name of a frame
  # cname: the cname that represents the user
  #
  CuesSender instproc init { path cname } {
          # initialize some variables
          $self instvar cname_ cues_
          set cname_ $cname
          # FIXME change so client can specify
          set cues_ "hand ear yes no"
  
          # create the cues buttons
          $self instvar top_
          set top_ $path
          foreach c $cues_ {
                  $self set ${c}_b_ [$self create_cue $c]
                  pack $top_.${c} -side left
          }
  }
  
  #
  # Create a cue checkbutton
  #
  CuesSender instproc create_cue { cue } {
          $self instvar top_
          set cb [new CheckButton $top_.${cue} \
                   -bitmap sm_${cue} -command "$self send $cue" \
                   -onvalue ${cue}_on -offvalue ${cue}_off \
                   -width 20 -height 20 -anchor w ]
          $cb set-val ${cue}_off
          return $cb
  }
 
 CuesSender instproc destroy { } {
         $self next
 }
 
 #
 # Send cue message whenever the user click on a
 # cue button. If the checkbutton is clicked down,
 # send a message that says this particular cue
 # is one, otherwise, send a message that cancels
 # this cue.
 #
 # (punt): because reliable multicast is probably
 # too heavyweight for this, we just send the
 # three times, hoping most participants can
 # get it.
 #
 CuesSender instproc send { cue } {
         CuesSender instvar glob_chan_
         $self instvar cname_ ${cue}_b_ ${cue}_after_ ${cue}_ids_
 
         # do nothing is global coordination bus does not exist
         # or there is no cname
         if { ![info exists glob_chan_] || "$cname_" == "" } {
                 return
         }
 
         # start sending messages
         if { "[[$self set ${cue}_b_] get-val]" == "${cue}_on" } {
                 # send the aware message three times
                 set ${cue}_after_ 1
                 for { set i 0; set t 0 } \
                     { $i < 1 } \
                     { incr i; incr t 500 } {
                         set ${cue}_ids_($i) \
                                 [after $t "$glob_chan_ send AWARE_$cue $cname_" ]
                 }
 
         } else {
                 # stop sending, if aware messages are queued up
                 # then cancel them
                 if [info exists ${cue}_after_] {
                         unset ${cue}_after_
                         foreach i [array names ${cue}_ids_] {
                                 after cancel [set ${cue}_ids_($i)]
                         }
                 }
 
                 # send the cancel message three times
                 for { set i 0; set t 0 } \
                     { $i < 1 } \
                     { incr i; incr t 500 } {
                         after $t "$glob_chan_ send UNAWARE_$cue $cname_"
                 }
         }
 }