Colors :
========

   Foreground and background colors are used to paint objects and labels. 
They are set by resources, according parameter divisions recorded below.

   Each type of object has standard colors. For example:

         atg*boxForeground :          AntiqueWhite4
         atg*boxBackground :          LemonChiffon

   Object types also have specific colors for objects when highlighted

         atg*hilightBoxForeground :   Red
         atg*hilightBoxBackground :   Lightgoldenrod

   Colors of labels are given according to both its type (struct, behav, 
logic or hook) and the type of its object.

         atg*behavLabelBoxForeground : HotPink4
         atg*structLabelBoxForeground: SteelBlue4
         atg*logicLabelBoxForeground : darkgoldenrod4
         atg*hookLabelBoxForeground  : darkgreen

   Highlighted labels have all the same color, disregarding types.

         atg*hilightNameForeground :   salmon
         atg*hilightNameBackground :   peru


   You can give a new color to a graphic object (to the whole
selection if the object is selected) by menu. The menu button are
<Attributes>:<Foreground> and <Attributes>:<Background>.  The range of
available colors in the menu is also set by resource and cannot be
dynamically changed from atg. In particular the number of such color
buttons must be set by resource.

  The <Default> button of the <Foreground> and <Background> menus
resets color to original according to types.  The
<Attributes>:<Background>:<Visible On/Off> button allows or disallows
background filling on individual objects or selections. Originally
only boxes do not have visible backgrounds.