[Andy]

Try this:

 
#make a popup menu
menu .rightmenu -tearoff false 
.rightmenu add command -label "Select All" -command "ac3d select_all"
 
# bind a right click (button 3) to view 0 (top left view window)
bind $ToglWinName(0) <3> { tk_popup .rightmenu %X %Y}