NAME

       SlotComp, SlotView, HSlotComp, HSlotView, VSlotComp, VSlotView, SlotGraphic, PSSlot - abstract base class
       and  subclasses  for  slot  connector  subject  and  view; and structured graphic and PostScript external
       representation classes for slots

SYNOPSIS

       #include <Unidraw/Components/slot.h>

DESCRIPTION

       SlotComp is a Connector subclass that supports connectivity with one degree of freedom.  It serves as  an
       abstract  base  class from which to derive HSlotComp and VSlotComp, which support horizontal and vertical
       orientations.  The slot component classes use SlotGraphics to store their graphical attributes.  SlotView
       is an abstract subclass of ConnectorView for displaying slots. HSlotView and VSlotView are SlotViews that
       display slots with the corresponding orientations.  Finally, PSSlot is a PostScriptView that externalizes
       the slot subject's information in PostScript form.

SLOTCOMP PUBLIC OPERATIONS

       virtual void Interpret(Command*)
       virtual void Uninterpret(Command*)
              SlotComp (un)interprets a subset of commands  that  connectors  can  generally  interpret,  namely
              MoveCmd, BrushCmd, AlignCmd, MobilityCmd, DeleteCmd, and CutCmd.

       virtual Mobility GetMobility()
       virtual void SetMobility(Mobility)
              SlotComp  redefines  these  functions  to return and assign its _mobility protected member.  Slots
              have fixed mobility initially.

       Slot* GetSlot()
              Return the Slot graphic that defines the line's attributes.  GetSlot is  simply  a  more  specific
              form of the GetGraphic operation.

SLOTCOMP PROTECTED OPERATIONS

       SlotComp(SlotGraphic* = nil)
              The  constructor takes an optional SlotGraphic that defines the slot's graphical attributes. It is
              protected to prevent instantiation, since SlotComp is an abstract class.

       void SetOrientation(SlotGraphic*, Orientation)
              Define the orientation of the SlotComp's SlotGraphic.  Only SlotComp can specify this  SlotGraphic
              attribute; HSlotComp and VSlotComp subclasses set it to reflect their respective orientations.

SLOTVIEW PUBLIC OPERATIONS

       virtual void Interpret(Command*)
              SlotView interprets AlignToGridCmd to align its starting point to the grid.

       virtual Manipulator* CreateManipulator(
          Viewer*, Event&, Transformer*, Tool*
       )

       virtual void InterpretManipulator(Manipulator*)
              SlotViews  respond only to manipulation by GraphicCompTools, MoveTools, and ConnectTools. SlotView
              inherits its MoveTool response from ConnectorView.  GraphicCompTool will let the user sweep out  a
              crosshaired  rectangle that reflects the slot's size and orientation.  Creation will be influenced
              by gravity, if any. SlotView creates a ConnectManip in response to  the  ConnectTool,  which  will
              exhibit  a  gravational  attraction  to  potential  target  connectors.   SlotView  will produce a
              ConnectCmd to connect the slot to its target. A slot connected in this way will  receive  floating
              mobility.

       SlotComp* GetSlotComp()
              Return the subject.

SLOTVIEW PROTECTED OPERATIONS

       SlotView(SlotComp* = nil)
              Create  an  SlotView,  optionally  supplying the subject.  The constructor is protected to prevent
              instantiation.

       SlotGraphic* GetSlot()
              Return the SlotGraphic that defines the slot's attributes.  GetSlot is simply a more specific form
              of the GetGraphic operation.

       virtual SlotComp* NewSubject(SlotGraphic*)
              A helper function that creates a SlotComp subject with  the  given  slot  graphic.  This  function
              produces  the proper subject when the GraphicCompTool's manipulator is interpreted.  HSlotView and
              VSlotView  redefine  this  operation  to  return  the  corresponding  SlotComp  subclasses,   thus
              eliminating the need to reimplement InterpretManipulator.

       Manipulator* CreateGraphicCompManip(
           Viewer*, Event&, Transformer*, Tool*
       )

       Manipulator* CreateConnectManip(
           Viewer*, Event&, Transformer*, Tool*
       )

       Command* InterpretGraphicCompManip(Manipulator*)
       Command* InterpretConnectManip(Manipulator*)
              Helper  functions  used  by CreateManipulator and InterpretManipulator to create and interpret the
              manipulators associated with GraphicCompTool and ConnectTool.

SLOTGRAPHIC PUBLIC OPERATIONS

       SlotGraphic(Coord, Coord, Coord, Graphic* = nil)
              Create a SlotGraphic, specifying the starting point, length, and optionally a graphic  from  which
              to obtain its default graphics attributes.

       void GetOriginal(Coord&, Coord&, Coord&)
              Return the SlotGraphic's original geometry parameters as specified in the constructor.

PSSLOT PUBLIC OPERATIONS

       PSSlot(SlotComp* = nil)
              Construct a PostScript external representation of the given subject, if any.

SEE ALSO

       BrushCmd(3U),     ConnectTool(3U),     Connector(3U),     ConnectorView3U),    Event(3I),    Graphic(3U),
       GraphicCompTool(3U),  Grid(3U),  MoveTool(3U),   PatternCmd(3U),   PostScriptView(3U),   Transformer(3I),
       Viewer(3U), align(3U), edit(3U), globals(3U), manips(3U), transforms(3U)

Unidraw                                          23 January 1991                                    SlotComp(3U)