NAME
       canvas - Create and manipulate canvas widgets

SYNOPSIS
       canvas pathName ?options?

STANDARD OPTIONS
       -background           -insertborderwidth   -selectborderwidth
       -borderwidth          -insertofftime       -selectforeground
       -cursor               -insertontime        -takefocus
       -highlightbackground  -insertwidth         -xscrollcommand
       -highlightcolor       -relief              -yscrollcommand
       -highlightthickness   -state
       -insertbackground     -selectbackground

       See  the  options manual entry for details on the standard
       options.

WIDGET-SPECIFIC OPTIONS
       Command-Line Name:-closeenough
       Database Name:  closeEnough
       Database Class: CloseEnough

              Specifies a  floating-point  value  indicating  how
              close the mouse cursor must be to an item before it
              is considered to be ``inside'' the item.   Defaults
              to 1.0.

       Command-Line Name:-confine
       Database Name:  confine
       Database Class: Confine

              Specifies a boolean value that indicates whether or
              not it should be allowable to set the canvas's view
              outside  the  region  defined  by  the scrollRegion
              argument.  Defaults to true, which means  that  the
              view  will be constrained within the scroll region.

       Command-Line Name:-height
       Database Name:  height
       Database Class: Height

              Specifies a desired window height that  the  canvas
              widget  should  request  from its geometry manager.
              The value may be specified  in  any  of  the  forms
              described in the COORDINATES section below.

       Command-Line Name:-scrollregion
       Database Name:  scrollRegion
       Database Class: ScrollRegion

              Specifies  a  list with four coordinates describing
              the left, top, right, and bottom coordinates  of  a
              rectangular   region.   This  region  is  used  for
              scrolling purposes and  is  considered  to  be  the
              boundary of the information in the canvas.  Each of
              the coordinates may be  specified  in  any  of  the
              forms given in the COORDINATES section below.

       Command-Line Name:-state
       Database Name:  state
       Database Class: State

              Modifies  the  default  state  of  the canvas where
              state may be set to one of:  normal,  disabled,  or
              hidden.  Individual  canvas  objects all have their
              own state option which  may  override  the  default
              state.   Many  options can take separate specifica-
              tions such that the appearance of the item  can  be
              different in different situations. The options that
              start with active control the appearence  when  the
              mouse pointer is over it, while the option starting
              with disabled  controls  the  appearence  when  the
              state is disabled.  Canvas items which are disabled
              will not react to canvas bindings.

       Command-Line Name:-width
       Database Name:  width
       Database Class: width

              Specifies a desired window width  that  the  canvas
              widget  should  request  from its geometry manager.
              The value may be specified  in  any  of  the  forms
              described in the COORDINATES section below.

       Command-Line Name:-xscrollincrement
       Database Name:  xScrollIncrement
       Database Class: ScrollIncrement

              Specifies an increment for horizontal scrolling, in
              any of the usual forms permitted  for  screen  dis-
              tances.   If  the  value  of this option is greater
              than zero, the horizontal view in the  window  will
              be  constrained  so that the canvas x coordinate at
              the left edge of the window is always an even  mul-
              tiple  of xScrollIncrement;  furthermore, the units
              for scrolling (e.g., the change in  view  when  the
              left  and right arrows of a scrollbar are selected)
              will also be xScrollIncrement.   If  the  value  of
              this  option  is  less  than or equal to zero, then
              horizontal scrolling is unconstrained.

       Command-Line Name:-yscrollincrement
       Database Name:  yScrollIncrement
       Database Class: ScrollIncrement

              Specifies an increment for vertical  scrolling,  in
              any   of  the  usual  forms  permitted  for  screen
              distances.  If the value of this option is  greater
              than  zero, the vertical view in the window will be
              constrained so that the canvas y coordinate at  the
              top  edge  of the window is always an even multiple
              of yScrollIncrement;  furthermore,  the  units  for
              scrolling  (e.g.,  the  change in view when the top
              and bottom arrows of a scrollbar are selected) will
              also  be  yScrollIncrement.   If  the value of this
              option is less than or equal to zero, then vertical
              scrolling is unconstrained.


INTRODUCTION
       The  canvas  command  creates  a  new window (given by the
       pathName argument) and makes  it  into  a  canvas  widget.
       Additional  options,  described above, may be specified on
       the command line or in the option  database  to  configure
       aspects  of  the canvas such as its colors and 3-D relief.
       The canvas command returns its pathName argument.  At  the
       time  this command is invoked, there must not exist a win-
       dow named pathName, but pathName's parent must exist.

       Canvas widgets implement structured  graphics.   A  canvas
       displays  any  number  of  items, which may be things like
       rectangles, circles, lines, and text.  Items may be manip-
       ulated  (e.g.  moved  or  re-colored)  and commands may be
       associated with items in much the same way that  the  bind
       command allows commands to be bound to widgets.  For exam-
       ple, a particular command may be associated with the <But-
       ton-1>  event so that the command is invoked whenever but-
       ton 1 is pressed with the mouse cursor over an item.  This
       means that items in a canvas can have behaviors defined by
       the Tcl scripts bound to them.


DISPLAY LIST
       The items in a canvas are ordered for purposes of display,
       with  the  first  item in the display list being displayed
       first, followed by the next item in the list, and  so  on.
       Items  later  in  the  display list obscure those that are
       earlier in the display list and are sometimes referred  to
       as  being ``on top'' of earlier items.  When a new item is
       created it is placed at the end of the  display  list,  on
       top  of  everything  else.  Widget commands may be used to
       re-arrange the order of the display list.

       Window items are an exception to  the  above  rules.   The
       underlying  window systems require them always to be drawn
       on top of other items.  In addition, the stacking order of
       window  items  is not affected by any of the canvas widget
       commands; you must use the raise  and  lower  Tk  commands
       instead.
ITEM IDS AND TAGS
       Items  in  a  canvas  widget may be named in either of two
       ways: by id or by tag.  Each item has a unique identifying
       number  which is assigned to that item when it is created.
       The id of an item never changes and id numbers  are  never
       re-used within the lifetime of a canvas widget.

       Each item may also have any number of tags associated with
       it.  A tag is just a string of characters, and it may take
       any form except that of an integer.  For example, ``x123''
       is OK but ``123'' isn't.  The same tag may  be  associated
       with many different items.  This is commonly done to group
       items in  various  interesting  ways;   for  example,  all
       selected items might be given the tag ``selected''.

       The  tag  all  is implicitly associated with every item in
       the canvas;  it may be used to invoke  operations  on  all
       the items in the canvas.

       The tag current is managed automatically by Tk; it applies
       to the current item, which is the topmost item whose drawn
       area  covers  the  position  of  the mouse cursor.  If the
       mouse is not in the canvas widget or is not over an  item,
       then no item has the current tag.

       When  specifying  items  in canvas widget commands, if the
       specifier is an integer then it is assumed to refer to the
       single  item  with  that  id.   If the specifier is not an
       integer, then it is assumed to refer to all of  the  items
       in the canvas that have a tag matching the specifier.  The
       symbol tagOrId is used below to indicate that an  argument
       specifies either an id that selects a single item or a tag
       that selects zero or more items.

       tagOrId may contain a logical expressions of tags by using
       operators:  '&&',  '||', '^' '!', and parenthezised subex-
       pressions.  For example:
                    .c find withtag {(a&&!b)||(!a&&b)}
       or equivalently:
                    .c find withtag {a^b}
       will find only those items with either "a"  or  "b"  tags,
       but not both.

       Some  widget  commands  only operate on a single item at a
       time;  if tagOrId is specified in a way that names  multi-
       ple  items, then the normal behavior is for the command to
       use the first (lowest) of these items in the display  list
       that is suitable for the command.  Exceptions are noted in
       the widget command descriptions below.


COORDINATES
       All coordinates related to canvases are stored  as  float-
       ing-point   numbers.    Coordinates   and   distances  are
       specified in screen units, which are  floating-point  num-
       bers optionally followed by one of several letters.  If no
       letter is supplied then the distance is in pixels.  If the
       letter  is  m  then  the distance is in millimeters on the
       screen;  if it is c then the distance is in centimeters; i
       means  inches,  and  p  means printers points (1/72 inch).
       Larger y-coordinates refer to points lower on the  screen;
       larger x-coordinates refer to points farther to the right.
       Coordinates can be specified either as an even  number  of
       parameters,  or  as  a single list parameter containing an
       even number of x and y coordinate values.


TRANSFORMATIONS
       Normally the origin of the canvas coordinate system is  at
       the upper-left corner of the window containing the canvas.
       It is possible to adjust the origin of the canvas  coordi-
       nate system relative to the origin of the window using the
       xview and yview widget commands;  this is  typically  used
       for  scrolling.   Canvases do not support scaling or rota-
       tion of the canvas coordinate system relative to the  win-
       dow coordinate system.

       Individual  items may be moved or scaled using widget com-
       mands described below, but they may not be rotated.


INDICES
       Text items support the notion of an index for  identifying
       particular  positions within the item.  In a similar fash-
       ion, line and polygon items support index for identifying,
       inserting  and  deleting  subsets  of  their  coordinates.
       Indices are used for commands such as inserting or  delet-
       ing  a range of characters or coordinates, and setting the
       insertion cursor position. An index may  be  specified  in
       any  of a number of ways, and different types of items may
       support different  forms  for  specifying  indices.   Text
       items  support  the  following forms for an index;  if you
       define new types of text-like items, it would be advisable
       to support as many of these forms as practical.  Note that
       it is possible to refer to the character  just  after  the
       last  one  in  the  text item;  this is necessary for such
       tasks as inserting new text at the end of the item.  Lines
       and  Polygons  don't  support the insertion cursor and the
       selection. Their indixes are supposed to be  even  always,
       because coordinates always appear in pairs.

       number    A  decimal  number  giving  the  position of the
                 desired  character  within  the  text  item.   0
                 refers  to  the  first  character, 1 to the next
                 character, and so on. If  indexes  are  odd  for
                 lines  and  polygons, they will be automatically
                 decremented by one.  A number  less  than  0  is
                 treated as if it were zero, and a number greater
                 than the length of the text item is  treated  as
                 if it were equal to the length of the text item.
                 For polygons, numbers less  than  0  or  greater
                 then  the  length of the coordinate list will be
                 adjusted by adding or  substracting  the  length
                 until the result is between zero and the length,
                 inclusive.

       end       Refers to the character or coordinate just after
                 the  last one in the item (same as the number of
                 characters or coordinates in the item).

       insert    Refers to the character just  before  which  the
                 insertion  cursor  is  drawn  in  this item. Not
                 valid for lines and polygons.

       sel.first Refers to the first selected  character  in  the
                 item.   If the selection isn't in this item then
                 this form is illegal.

       sel.last  Refers to the last  selected  character  in  the
                 item.   If the selection isn't in this item then
                 this form is illegal.

       @x,y      Refers to the character  or  coordinate  at  the
                 point given by x and y, where x and y are speci-
                 fied in the coordinate system of the canvas.  If
                 x  and  y lie outside the coordinates covered by
                 the text item, then they refer to the  first  or
                 last  character  in  the line that is closest to
                 the given point.


DASH PATTERNS
       Many items support the notion of an dash pattern for  out-
       lines.

       The first possible syntax is a list of integers. Each ele-
       ment represents the number of pixels of  a  line  segment.
       Only the odd segments are drawn using the "outline" color.
       The other segments are drawn transparant.

       The second possible syntax is a character list  containing
       only  5 possible characters [.,-_ ]. The space can be used
       to enlarge the space between other line elements, and  can
       not  occur as the first position in the string. Some exam-
       ples:
           -dash .= -dash {2 4}
           -dash -     = -dash {6 4}
           -dash -.    = -dash {6 4 2 4}
           -dash -..   = -dash {6 4 2 4 2 4}
           -dash {. }  = -dash {2 8}
           -dash ,= -dash {4 4}
       The main difference of this syntax with  the  previous  is
       that it it shape-conserving. This means that all values in
       the dash list will be multiplied by the line width  before
       display. This assures that "." will always be displayed as
       a dot and "-" always as a  dash  regardless  of  the  line
       width.

       On  systems  which support only a limited set of dash pat-
       terns, the dash pattern will be displayed as  the  closest
       dash  pattern  that is available.  For example, on Windows
       only the first 4 of the above examples are available.  The
       last 2 examples will be displayed identically to the first
       one.


WIDGET COMMAND
       The canvas command creates a new Tcl command whose name is
       pathName.   This  command  may  be  used to invoke various
       operations on the widget.  It has  the  following  general
       form:
              pathName option ?arg arg ...?
       Option  and  the  args determine the exact behavior of the
       command.  The following widget commands are  possible  for
       canvas widgets:

       pathName addtag tag searchSpec ?arg arg ...?
              For  each item that meets the constraints specified
              by searchSpec and the args, add tag to the list  of
              tags  associated  with the item if it isn't already
              present on that list.  It is possible that no items
              will  satisfy  the  constraints given by searchSpec
              and args, in which case the command has no  effect.
              This  command  returns  an  empty string as result.
              SearchSpec and arg's may take any of the  following
              forms:

              above tagOrId
                     Selects  the item just after (above) the one
                     given by tagOrId in the  display  list.   If
                     tagOrId denotes more than one item, then the
                     last (topmost) of these items in the display
                     list is used.

              all    Selects all the items in the canvas.

              below tagOrId
                     Selects the item just before (below) the one
                     given by tagOrId in the  display  list.   If
                     tagOrId denotes more than one item, then the
                     first (lowest) of these items in the display
                     list is used.

              closest x y ?halo? ?start?
                     Selects  the item closest to the point given
                     by x and y.  If more than one item is at the
                     same  closest distance (e.g. two items over-
                     lap the point), then the top-most  of  these
                     items  (the last one in the display list) is
                     used.  If halo is specified, then it must be
                     a  non-negative value.  Any item closer than
                     halo to the point is considered  to  overlap
                     it.   The start argument may be used to step
                     circularly through all  the  closest  items.
                     If  start  is  specified,  it  names an item
                     using a tag or id (if by tag, it selects the
                     first  item  in  the  display  list with the
                     given tag).  Instead of selecting  the  top-
                     most closest item, this form will select the
                     topmost closest item that is below start  in
                     the  display  list;  if no such item exists,
                     then the selection behaves as if  the  start
                     argument had not been specified.

              enclosed x1 y1 x2 y2
                     Selects  all  the  items completely enclosed
                     within the rectangular region given  by  x1,
                     y1,  x2, and y2.  X1 must be no greater then
                     x2 and y1 must be no greater than y2.

              overlapping x1 y1 x2 y2
                     Selects all the items that  overlap  or  are
                     enclosed within the rectangular region given
                     by x1, y1,  x2,  and  y2.   X1  must  be  no
                     greater  then  x2  and y1 must be no greater
                     than y2.

              withtag tagOrId
                     Selects all the items given by tagOrId.

       pathName bbox tagOrId ?tagOrId tagOrId ...?
              Returns a list with four elements giving an approx-
              imate  bounding  box for all the items named by the
              tagOrId arguments.  The list has the form  ``x1  y1
              x2  y2'' such that the drawn areas of all the named
              elements are within the region bounded by x1 on the
              left, x2 on the right, y1 on the top, and y2 on the
              bottom.  The  return  value  may  overestimate  the
              actual  bounding  box by a few pixels.  If no items
              match any of the tagOrId arguments or if the match-
              ing items have empty bounding boxes (i.e. they have
              nothing  to  display)  then  an  empty  string   is
              returned.

       pathName bind tagOrId ?sequence? ?command?
              This  command associates command with all the items
              given by  tagOrId  such  that  whenever  the  event
              sequence  given  by  sequence occurs for one of the
              items the command will  be  invoked.   This  widget
              command  is similar to the bind command except that
              it operates on items in a canvas rather than entire
              widgets.   See  the  bind manual entry for complete
              details on the syntax of sequence and the substitu-
              tions  performed on command before invoking it.  If
              all arguments are specified then a new  binding  is
              created,  replacing  any  existing  binding for the
              same sequence and tagOrId (if the  first  character
              of command is ``+'' then command augments an exist-
              ing binding rather than  replacing  it).   In  this
              case  the return value is an empty string.  If com-
              mand is omitted then the command returns  the  com-
              mand associated with tagOrId and sequence (an error
              occurs if there is no such binding).  If both  com-
              mand  and  sequence  are  omitted  then the command
              returns a list of all the sequences for which bind-
              ings have been defined for tagOrId.

              The only events for which bindings may be specified
              are those related to the mouse and  keyboard  (such
              as Enter, Leave, ButtonPress, Motion, and KeyPress)
              or virtual events.  The handling of events in  can-
              vases uses the current item defined in ITEM IDS AND
              TAGS above.  Enter and Leave events trigger for  an
              item  when it becomes the current item or ceases to
              be the current item; note  that  these  events  are
              different  than Enter and Leave events for windows.
              Mouse-related events are directed  to  the  current
              item, if any.  Keyboard-related events are directed
              to the focus item, if any  (see  the  focus  widget
              command  below  for  more  on  this).  If a virtual
              event is used in a binding, that binding can  trig-
              ger  only  if  the  virtual  event is defined by an
              underlying mouse-related or keyboard-related event.

              It  is  possible  for  multiple bindings to match a
              particular event.  This could occur,  for  example,
              if one binding is associated with the item's id and
              another is associated with one of the item's  tags.
              When  this occurs, all of the matching bindings are
              invoked.  A binding associated with the all tag  is
              invoked  first, followed by one binding for each of
              the item's tags (in order), followed by  a  binding
              associated with the item's id.  If there are multi-
              ple matching bindings for a single tag,  then  only
              the  most  specific binding is invoked.  A continue
              command in a binding script terminates that script,
              and  a  break  command  terminates  that script and
              skips any remaining scripts for the event, just  as
              for the bind command.

              If  bindings  have been created for a canvas window
              using the bind command, then they  are  invoked  in
              addition to bindings created for the canvas's items
              using the bind widget command.   The  bindings  for
              items  will  be  invoked before any of the bindings
              for the window as a whole.

       pathName canvasx screenx ?gridspacing?
              Given a window x-coordinate in the canvas  screenx,
              this  command  returns the canvas x-coordinate that
              is displayed at that location.  If  gridspacing  is
              specified, then the canvas coordinate is rounded to
              the nearest multiple of gridspacing units.

       pathName canvasy screeny ?gridspacing?
              Given a window y-coordinate in the  canvas  screeny
              this  command  returns the canvas y-coordinate that
              is displayed at that location.  If  gridspacing  is
              specified, then the canvas coordinate is rounded to
              the nearest multiple of gridspacing units.

       pathName cget option
              Returns the  current  value  of  the  configuration
              option given by option.  Option may have any of the
              values accepted by the canvas command.

       pathName configure ?option? ?value? ?option value ...?
              Query or modify the configuration  options  of  the
              widget.   If no option is specified, returns a list
              describing all of the available options  for  path-
              Name  (see  Tk_ConfigureInfo for information on the
              format of this list).  If option is specified  with
              no  value, then the command returns a list describ-
              ing the one named option (this list will be identi-
              cal  to  the  corresponding  sublist  of  the value
              returned if no option is  specified).   If  one  or
              more  option-value  pairs  are  specified, then the
              command modifies the given widget option(s) to have
              the  given  value(s);   in  this  case  the command
              returns an empty string.  Option may  have  any  of
              the values accepted by the canvas command.

       pathName coords tagOrId ?x0 y0 ...?

       pathName coords tagOrId ?coordList?
              Query  or  modify  the  coordinates  that define an
              item.  If no coordinates are specified,  this  com-
              mand  returns a list whose elements are the coordi-
              nates of the item named by tagOrId.  If coordinates
              are  specified, then they replace the current coor-
              dinates for the named item.  If tagOrId  refers  to
              multiple  items,  then the first one in the display
              list is used.

       pathName create type x y ?x y ...? ?option value ...?
       pathName create type coordList ?option value ...?
              Create a new item in pathName of  type  type.   The
              exact format of the arguments after type depends on
              type, but usually they consist of  the  coordinates
              for  one or more points, followed by specifications
              for zero or more item options.  See the subsections
              on individual item types below for more on the syn-
              tax of this command.  This command returns  the  id
              for the new item.

       pathName dchars tagOrId first ?last?
              For  each item given by tagOrId, delete the charac-
              ters, or coordinates, in the range given  by  first
              and last, inclusive.  If some of the items given by
              tagOrId don't support indexing operations then they
              ignore dchars.  Text items interpret first and last
              as indices to a character, line and  polygon  items
              interpret  them  indices  to  a  coordinate (an x,y
              pair).  Indices are described in INDICES above.  If
              last  is  omitted, it defaults to first.  This com-
              mand returns an empty string.

       pathName delete ?tagOrId tagOrId ...?
              Delete each of the items given by each tagOrId, and
              return an empty string.

       pathName dtag tagOrId ?tagToDelete?
              For  each of the items given by tagOrId, delete the
              tag given by tagToDelete from  the  list  of  those
              associated  with the item.  If an item doesn't have
              the tag tagToDelete then the item is unaffected  by
              the  command.   If  tagToDelete  is omitted then it
              defaults to tagOrId.  This command returns an empty
              string.

       pathName find searchCommand ?arg arg ...?
              This  command  returns a list consisting of all the
              items  that  meet  the  constraints  specified   by
              searchCommand  and  arg's.   SearchCommand and args
              have any of the forms accepted by the  addtag  com-
              mand.   The  items  are returned in stacking order,
              with the lowest item first.

       pathName focus ?tagOrId?
              Set the keyboard focus for the canvas widget to the
              item  given  by tagOrId.  If tagOrId refers to sev-
              eral items, then the focus is set to the first such
              item  in  the display list that supports the inser-
              tion cursor.   If  tagOrId  doesn't  refer  to  any
              items,  or  if  none  of them support the insertion
              cursor, then the focus isn't changed.   If  tagOrId
              is an empty string, then the focus item is reset so
              that no item has the  focus.   If  tagOrId  is  not
              specified  then  the command returns the id for the
              item that currently has  the  focus,  or  an  empty
              string if no item has the focus.

              Once  the  focus  has been set to an item, the item
              will display the insertion cursor and all  keyboard
              events  will  be  directed to that item.  The focus
              item within a canvas and the focus  window  on  the
              screen  (set  with  the  focus command) are totally
              independent: a given item doesn't actually have the
              input focus unless (a) its canvas is the focus win-
              dow and (b) the item is the focus item  within  the
              canvas.   In  most  cases it is advisable to follow
              the focus widget command with the focus command  to
              set  the  focus  window to the canvas (if it wasn't
              there already).

       pathName gettags tagOrId
              Return a list whose elements are the  tags  associ-
              ated  with  the  item given by tagOrId.  If tagOrId
              refers to more than one item,  then  the  tags  are
              returned  from  the  first such item in the display
              list.  If tagOrId doesn't refer to any items, or if
              the  item contains no tags, then an empty string is
              returned.

       pathName icursor tagOrId index
              Set the position of the insertion  cursor  for  the
              item(s) given by tagOrId to just before the charac-
              ter whose position is given by index.  If  some  or
              all  of the items given by tagOrId don't support an
              insertion cursor then this command has no effect on
              them.   See  INDICES above for a description of the
              legal forms for index.  Note:  the insertion cursor
              is only displayed in an item if that item currently
              has the keyboard  focus  (see  the  widget  command
              focus,  below),  but the cursor position may be set
              even when the item doesn't have  the  focus.   This
              command returns an empty string.

       pathName index tagOrId index
              This  command  returns  a decimal string giving the
              numerical index  within  tagOrId  corresponding  to
              index.   Index  gives  a textual description of the
              desired position as  described  in  INDICES  above.
              Text  items interpret index as an index to a  char-
              acter, line and polygon items interpret  it  as  an
              index  to  a  coordinate (an x,y pair).  The return
              value is guaranteed to lie between 0 and the number
              of  characters,  or  coordinates,  within the item,
              inclusive.  If tagOrId refers  to  multiple  items,
              then  the  index is processed in the first of these
              items that supports indexing operations (in display
              list order).
       pathName insert tagOrId beforeThis string
              For each of the items given by tagOrId, if the item
              supports text or coordinate, insertion then  string
              is  inserted  into  the item's text just before the
              character, or coordinate, whose  index  is  before-
              This.   Text items interpret beforethis as an index
              to a  character, line and polygon  items  interpret
              it  as an index to a coordinate (an x,y pair).  For
              lines and polygons the string must be a valid coor-
              dinate sequence.  See INDICES above for information
              about the forms allowed for beforeThis.  This  com-
              mand returns an empty string.

       pathName itemcget tagOrId option
              Returns  the  current  value  of  the configuration
              option for the item given by tagOrId whose name  is
              option.  This command is similar to the cget widget
              command except that it applies to a particular item
              rather than the widget as a whole.  Option may have
              any of the values accepted  by  the  create  widget
              command when the item was created.  If tagOrId is a
              tag that refers to more than one  item,  the  first
              (lowest) such item is used.

       pathName  itemconfigure  tagOrId  ?option?  ?value?
       ?option value ...?
              This  command  is  similar  to the configure widget
              command  except  that  it  modifies   item-specific
              options  for  the items given by tagOrId instead of
              modifying options for the  overall  canvas  widget.
              If  no option is specified, returns a list describ-
              ing all of the available options for the first item
              given by tagOrId (see Tk_ConfigureInfo for informa-
              tion on the format of this  list).   If  option  is
              specified with no value, then the command returns a
              list describing the one  named  option  (this  list
              will  be  identical to the corresponding sublist of
              the value returned if no option is specified).   If
              one  or more option-value pairs are specified, then
              the command modifies the given widget option(s)  to
              have  the given value(s) in each of the items given
              by tagOrId;  in this case the  command  returns  an
              empty  string.  The options and values are the same
              as those permissible in the create  widget  command
              when  the  item(s)  were  created; see the sections
              describing individual item types below for  details
              on the legal options.

       pathName lower tagOrId ?belowThis?
              Move  all  of  the  items given by tagOrId to a new
              position in the display list just before  the  item
              given by belowThis.  If tagOrId refers to more than
              one item then all are moved but the relative  order
              of  the moved items will not be changed.  BelowThis
              is a tag or id;  if it refers to more than one item
              then  the first (lowest) of these items in the dis-
              play list is used as the destination  location  for
              the  moved items.  Note: this command has no effect
              on window items.  Window items always obscure other
              item  types, and the stacking order of window items
              is determined by the raise and lower commands,  not
              the  raise  and lower widget commands for canvases.
              This command returns an empty string.

       pathName move tagOrId xAmount yAmount
              Move each of the items given by tagOrId in the can-
              vas  coordinate  space  by adding xAmount to the x-
              coordinate of each point associated with  the  item
              and yAmount to the y-coordinate of each point asso-
              ciated with the  item.   This  command  returns  an
              empty string.

       pathName postscript ?option value option value ...?
              Generate  a  Postscript  representation for part or
              all of the canvas.  If the -file option  is  speci-
              fied  then  the Postscript is written to a file and
              an  empty  string  is  returned;    otherwise   the
              Postscript  is  returned  as the result of the com-
              mand.  If the interpreter that owns the  canvas  is
              marked  as  safe,  the  operation will fail because
              safe interpreters are not allowed to  write  files.
              If  the  -channel option is specified, the argument
              denotes the name of a channel  already  opened  for
              writing. The Postscript is written to that channel,
              and the channel is left open for further writing at
              the  end  of the operation.  The Postscript is cre-
              ated in Encapsulated Postscript form using  version
              3.0 of the Document Structuring Conventions.  Note:
              by default Postscript is only generated for  infor-
              mation  that  appears in the canvas's window on the
              screen.  If the canvas is freshly  created  it  may
              still have its initial size of 1x1 pixel so nothing
              will appear in the Postscript.  To get around  this
              problem  either invoke the "update" command to wait
              for the canvas window to reach its final  size,  or
              else  use the -width and -height options to specify
              the area of the canvas to print.  The  option-value
              argument  pairs  provide  additional information to
              control the generation of Postscript.  The  follow-
              ing options are supported:

              -colormap varName
                     VarName  must  be the name of an array vari-
                     able that specifies a color mapping  to  use
                     in  the Postscript.  Each element of varName
                     must consist of Postscript  code  to  set  a
                     particular  color  value (e.g. ``1.0 1.0 0.0
                     setrgbcolor'').    When   outputting   color
                     information  in the Postscript, Tk checks to
                     see if there is an element of  varName  with
                     the  same name as the color.  If so, Tk uses
                     the value of the element as  the  Postscript
                     command  to  set  the color.  If this option
                     hasn't been specified, or if there isn't  an
                     entry  in varName for a given color, then Tk
                     uses the red, green,  and  blue  intensities
                     from the X color.

              -colormode mode
                     Specifies  how  to output color information.
                     Mode must be either color  (for  full  color
                     output),  gray  (convert all colors to their
                     gray-scale equivalents) or mono (convert all
                     colors to black or white).

              -file fileName
                     Specifies  the  name of the file in which to
                     write the Postscript.  If this option  isn't
                     specified then the Postscript is returned as
                     the result of the command instead  of  being
                     written to a file.

              -fontmap varName
                     VarName  must  be the name of an array vari-
                     able that specifies a font mapping to use in
                     the  Postscript.   Each  element  of varName
                     must consist of a Tcl  list  with  two  ele-
                     ments,  which are the name and point size of
                     a   Postscript   font.    When    outputting
                     Postscript  commands  for a particular font,
                     Tk checks to see if varName contains an ele-
                     ment  with  the  same  name as the font.  If
                     there is such  an  element,  then  the  font
                     information  contained  in  that  element is
                     used  in  the  Postscript.    Otherwise   Tk
                     attempts  to  guess  what Postscript font to
                     use.  Tk's guesses generally only  work  for
                     well-known fonts such as Times and Helvetica
                     and Courier, and only if  the  X  font  name
                     does  not  omit  any  dashes  up through the
                     point       size.        For        example,
                     -*-Courier-Bold-R-Normal--*-120-*  will work
                     but  *Courier-Bold-R-Normal*120*  will  not;
                     Tk needs the dashes to parse the font name).

              -height size
                     Specifies the height of the area of the can-
                     vas to print.  Defaults to the height of the
                     canvas window.

              -pageanchor anchor
                     Specifies which point of the printed area of
                     the  canvas should appear over the position-
                     ing point on the page (which is given by the
                     -pagex  and  -pagey  options).  For example,
                     -pageanchor n means that the top  center  of
                     the  area of the canvas being printed (as it
                     appears in the canvas window) should be over
                     the positioning point. Defaults to center.

              -pageheight size
                     Specifies  that  the  Postscript  should  be
                     scaled in both x and y so that  the  printed
                     area  is  size  high on the Postscript page.
                     Size consists  of  a  floating-point  number
                     followed by c for centimeters, i for inches,
                     m for  millimeters,  or  p  or  nothing  for
                     printer's  points  (1/72 inch).  Defaults to
                     the  height  of  the  printed  area  on  the
                     screen.   If both -pageheight and -pagewidth
                     are specified then  the  scale  factor  from
                     -pagewidth  is  used (non-uniform scaling is
                     not implemented).

              -pagewidth size
                     Specifies  that  the  Postscript  should  be
                     scaled  in  both x and y so that the printed
                     area is size wide on  the  Postscript  page.
                     Size  has  the same form as for -pageheight.
                     Defaults to the width of the printed area on
                     the   screen.    If   both  -pageheight  and
                     -pagewidth are specified then the scale fac-
                     tor  from  -pagewidth   is used (non-uniform
                     scaling is not implemented).

              -pagex position
                     Position gives the x-coordinate of the posi-
                     tioning  point on the Postscript page, using
                     any of the forms  allowed  for  -pageheight.
                     Used  in  conjunction  with  the  -pagey and
                     -pageanchor options to determine  where  the
                     printed area appears on the Postscript page.
                     Defaults to the center of the page.

              -pagey position
                     Position gives the y-coordinate of the posi-
                     tioning  point on the Postscript page, using
                     any of the forms  allowed  for  -pageheight.
                     Used  in  conjunction  with  the  -pagex and
                     -pageanchor options to determine  where  the
                     printed area appears on the Postscript page.
                     Defaults to the center of the page.

              -rotate boolean
                     Boolean specifies whether the  printed  area
                     is to be rotated 90 degrees.  In non-rotated
                     output the x-axis of the printed  area  runs
                     along   the  short  dimension  of  the  page
                     (``portrait'' orientation); in rotated  out-
                     put the x-axis runs along the long dimension
                     of  the  page  (``landscape''  orientation).
                     Defaults to non-rotated.

              -width size
                     Specifies  the width of the area of the can-
                     vas to print.  Defaults to the width of  the
                     canvas window.

              -x position
                     Specifies  the x-coordinate of the left edge
                     of the area of the  canvas  that  is  to  be
                     printed,  in  canvas coordinates, not window
                     coordinates.  Defaults to the coordinate  of
                     the left edge of the window.

              -y position
                     Specifies  the  y-coordinate of the top edge
                     of the area of the  canvas  that  is  to  be
                     printed,  in  canvas coordinates, not window
                     coordinates.  Defaults to the coordinate  of
                     the top edge of the window.

       pathName raise tagOrId ?aboveThis?
              Move  all  of  the  items given by tagOrId to a new
              position in the display list just  after  the  item
              given by aboveThis.  If tagOrId refers to more than
              one item then all are moved but the relative  order
              of  the moved items will not be changed.  AboveThis
              is a tag or id;  if it refers to more than one item
              then  the last (topmost) of these items in the dis-
              play list is used as the destination  location  for
              the  moved items.  Note: this command has no effect
              on window items.  Window items always obscure other
              item  types, and the stacking order of window items
              is determined by the raise and lower commands,  not
              the  raise  and lower widget commands for canvases.
              This command returns an empty string.

       pathName scale tagOrId xOrigin yOrigin xScale yScale
              Rescale all of the items given by tagOrId in canvas
              coordinate space.  XOrigin and yOrigin identify the
              origin for the scaling  operation  and  xScale  and
              yScale  identify  the  scale  factors for x- and y-
              coordinates, respectively (a scale  factor  of  1.0
              implies no change to that coordinate).  For each of
              the points defining each item, the x-coordinate  is
              adjusted  to  change the distance from xOrigin by a
              factor of xScale.  Similarly, each y-coordinate  is
              adjusted  to  change the distance from yOrigin by a
              factor of yScale.  This command  returns  an  empty
              string.

       pathName scan option args
              This  command is used to implement scanning on can-
              vases.  It has two forms, depending on option:

              pathName scan mark x y
                     Records x and y  and  the  canvas's  current
                     view;   used  in conjunction with later scan
                     dragto commands.  Typically this command  is
                     associated  with a mouse button press in the
                     widget and x and y are  the  coordinates  of
                     the mouse.  It returns an empty string.

              pathName scan dragto x y ?gain?.
                     This command computes the difference between
                     its x and y arguments (which  are  typically
                     mouse coordinates) and the x and y arguments
                     to the last scan mark command for  the  wid-
                     get.  It then adjusts the view by gain times
                     the difference in  coordinates,  where  gain
                     defaults  to  10.  This command is typically
                     associated with mouse motion events  in  the
                     widget,  to  produce  the effect of dragging
                     the canvas at high speed through its window.
                     The return value is an empty string.

       pathName select option ?tagOrId arg?
              Manipulates  the  selection in one of several ways,
              depending on option.  The command may take  any  of
              the  forms described below.  In all of the descrip-
              tions below, tagOrId must refer  to  an  item  that
              supports  indexing  and selection;  if it refers to
              multiple items then the first of  these  that  sup-
              ports  indexing  and  the selection is used.  Index
              gives a textual description of  a  position  within
              tagOrId, as described in INDICES above.

              pathName select adjust tagOrId index
                     Locate  the  end of the selection in tagOrId
                     nearest to the character given by index, and
                     adjust  that  end  of the selection to be at
                     index (i.e. including but not  going  beyond
                     index).   The  other end of the selection is
                     made the anchor point for future  select  to
                     commands.   If the selection isn't currently
                     in tagOrId then  this  command  behaves  the
                     same   as  the  select  to  widget  command.
                     Returns an empty string.

              pathName select clear
                     Clear the selection if it is in this widget.
                     If  the  selection isn't in this widget then
                     the command has no effect.  Returns an empty
                     string.

              pathName select from tagOrId index
                     Set  the selection anchor point for the wid-
                     get to be just before the character given by
                     index  in  the  item given by tagOrId.  This
                     command doesn't change  the  selection;   it
                     just sets the fixed end of the selection for
                     future select to commands.  Returns an empty
                     string.

              pathName select item
                     Returns  the id of the selected item, if the
                     selection is in an item in this canvas.   If
                     the  selection is not in this canvas then an
                     empty string is returned.

              pathName select to tagOrId index
                     Set the selection to consist of those  char-
                     acters  of  tagOrId  between  the  selection
                     anchor point and index.  The  new  selection
                     will  include  the character given by index;
                     it will include the character given  by  the
                     anchor  point  only if index is greater than
                     or equal to the anchor  point.   The  anchor
                     point  is  determined  by  the  most  recent
                     select adjust or  select  from  command  for
                     this  widget.  If the selection anchor point
                     for the widget isn't currently  in  tagOrId,
                     then  it  is set to the same character given
                     by index.  Returns an empty string.

       pathName type tagOrId
              Returns the type of the item given by tagOrId, such
              as  rectangle  or  text.  If tagOrId refers to more
              than one item, then the type of the first  item  in
              the  display  list is returned.  If tagOrId doesn't
              refer to any items at all then an empty  string  is
              returned.

       pathName xview  ?args?
              This  command is used to query and change the hori-
              zontal position of the information displayed in the
              canvas's  window.  It can take any of the following
              forms:

              pathName xview
                     Returns  a  list  containing  two  elements.
                     Each  element  is  a real fraction between 0
                     and 1;  together they describe the  horizon-
                     tal span that is visible in the window.  For
                     example, if the first element is .2 and  the
                     second  element  is  .6, 20% of the canvas's
                     area  (as  defined  by   the   -scrollregion
                     option)  is off-screen to the left, the mid-
                     dle 40% is visible in the window, and 40% of
                     the  canvas  is  off-screen  to  the  right.
                     These are the same values passed to  scroll-
                     bars via the -xscrollcommand option.

              pathName xview moveto fraction
                     Adjusts the view in the window so that frac-
                     tion of the total width  of  the  canvas  is
                     off-screen  to the left.  Fraction must be a
                     fraction between 0 and 1.

              pathName xview scroll number what
                     This command shifts the view in  the  window
                     left  or right according to number and what.
                     Number must be an  integer.   What  must  be
                     either  units or pages or an abbreviation of
                     one of these.  If what is  units,  the  view
                     adjusts  left  or  right  in  units  of  the
                     xScrollIncrement option, if  it  is  greater
                     than zero, or in units of one-tenth the win-
                     dow's width otherwise.   If  what  is  pages
                     then  the  view  adjusts  in  units of nine-
                     tenths the window's  width.   If  number  is
                     negative  then  information  farther  to the
                     left becomes visible;   if  it  is  positive
                     then   information   farther  to  the  right
                     becomes visible.

       pathName yview ?args?
              This command is used to query and change the verti-
              cal  position  of  the information displayed in the
              canvas's window.  It can take any of the  following
              forms:

              pathName yview
                     Returns  a  list  containing  two  elements.
                     Each element is a real  fraction  between  0
                     and  1;  together they describe the vertical
                     span that is visible  in  the  window.   For
                     example,  if the first element is .6 and the
                     second element is 1.0, the lowest 40% of the
                     canvas's  area (as defined by the -scrollre-
                     gion  option)  is  visible  in  the  window.
                     These  are the same values passed to scroll-
                     bars via the -yscrollcommand option.

              pathName yview moveto fraction
                     Adjusts the view in the window so that frac-
                     tion  of  the canvas's area is off-screen to
                     the top.  Fraction is a fraction  between  0
                     and 1.
              pathName yview scroll number what
                     This  command adjusts the view in the window
                     up or down according  to  number  and  what.
                     Number  must  be  an  integer.  What must be
                     either units or pages.  If  what  is  units,
                     the  view adjusts up or down in units of the
                     yScrollIncrement option, if  it  is  greater
                     than zero, or in units of one-tenth the win-
                     dow's height otherwise.  If  what  is  pages
                     then  the  view  adjusts  in  units of nine-
                     tenths the window's height.   If  number  is
                     negative  then  higher  information  becomes
                     visible;   if  it  is  positive  then  lower
                     information becomes visible.


OVERVIEW OF ITEM TYPES
       The  sections  below  describe  the various types of items
       supported by canvas widgets.  Each item type is character-
       ized  by two things: first, the form of the create command
       used to create instances of the type;  and second,  a  set
       of configuration options for items of that type, which may
       be used in the create and itemconfigure  widget  commands.
       Most items don't support indexing or selection or the com-
       mands related to them, such as index  and  insert.   Where
       items  do support these facilities, it is noted explicitly
       in the descriptions below.  At  present,  text,  line  and
       polygon  items  provide this support.  For lines and poly-
       gons the indexing facility is used to manipulate the coor-
       dinates of the item.


COMMON ITEM OPTIONS
       Many  items  share a common set of options.  These options
       are explained here, and then referred to  be  each  widget
       type for brevity.


       -dash pattern

       -activedash pattern

       -disableddash pattern
              This option specifies dash patterns for the normal,
              active state, and disabled state of an item.   pat-
              tern  may have any of the forms accepted by Tk_Get-
              Dash.  If the dash options  are  omitted  then  the
              default  is  a  solid outline.  See "DASH PATTERNS"
              for more information.

       -dashoffset offset
              The starting offset in pixels into the pattern pro-
              vided  by the -dash option.  -dashoffset is ignored
              if there is no -dash pattern.  The offset may  have
              any  of the forms described in the COORDINATES sec-
              tion above.

       -fill color

       -activefill color

       -disabledfill color
              Specifies the color to be used to fill item's area.
              in  its  normal, active, and disabled states, Color
              may have any of the forms accepted by  Tk_GetColor.
              If  color  is  an  empty string (the default), then
              then the item will not be  filled.   For  the  line
              item,  it  specifies  the  color of the line drawn.
              For the text  item,  it  specifies  the  foreground
              color of the text.

       -outline color

       -activeoutline color

       -disabledoutline color
              This option specifies the color that should be used
              to draw the outline of  the  item  in  its  normal,
              active  and disabled states.  Color may have any of
              the forms accepted  by  Tk_GetColor.   This  option
              defaults  to  black.   If  color is specified as an
              empty string then no outline is drawn for the item.

       -offset offset
              Specifies the offset of stipples.  The offset value
              can be of the form x,y or side, where side  can  be
              n, ne, e, se, s, sw, w, nw, or center. In the first
              case the origin is the origin of  the  toplevel  of
              the current window.  For the canvas itself and can-
              vas objects the origin is the  canvas  origin,  but
              putting # in front of the coordinate pair indicates
              using  the  toplevel  origin  instead.  For  canvas
              objects,  the  -offset option is used for stippling
              as well.  For the line and polygon canvas items you
              can  also  specify an index as argument, which con-
              nects the stipple origin to one of  the  coordinate
              points of the line/polygon.

       -outlinestipple bitmap

       -activeoutlinestipple bitmap

       -disabledoutlinestipple bitmap
              This  option specifies stipple patterns that should
              be used to draw the outline of the item in its nor-
              mal,  active  and  disabled states.  Indicates that
              the outline for the item should  be  drawn  with  a
              stipple   pattern;  bitmap  specifies  the  stipple
              pattern to use, in any of  the  forms  accepted  by
              Tk_GetBitmap.   If  the -outline option hasn't been
              specified then  this  option  has  no  effect.   If
              bitmap  is  an empty string (the default), then the
              outline is drawn in a solid fashion.

       -stipple bitmap

       -activestipple bitmap

       -disabledstipple bitmap
              This option specifies stipple patterns that  should
              be  used to fill the the item in its normal, active
              and disabled states.  bitmap specifies the  stipple
              pattern  to  use,  in  any of the forms accepted by
              Tk_GetBitmap.  If  the  -fill  option  hasn't  been
              specified  then  this  option  has  no  effect.  If
              bitmap is an empty string (the default), then fill-
              ing is done in a solid fashion.  For the text item,
              it affects the actual text.

       -state state
              This allows an item to override the canvas widget's
              global  state  option.   It  takes the same values:
              normal, disabled or hidden.

       -tags tagList
              Specifies a set of  tags  to  apply  to  the  item.
              TagList  consists  of  a  list  of tag names, which
              replace any existing tags for  the  item.   TagList
              may be an empty list.

       -width outlineWidth

       -activewidth outlineWidth

       -disabledwidth outlineWidth
              Specifies  the  width  of  the  outline to be drawn
              around the item's region, in its normal, active and
              disabled states.  outlineWidth may be in any of the
              forms described in the COORDINATES  section  above.
              If  the  -outline  option  has been specified as an
              empty string then this option has no effect.   This
              option  defaults  to  1.0.  For arcs, wide outlines
              will be drawn centered on the edges  of  the  arc's
              region.


ARC ITEMS
       Items  of  type  arc  appear  on the display as arc-shaped
       regions.  An arc is a section of an oval delimited by  two
       angles  (specified  by the -start and -extent options) and
       displayed in one of several ways (specified by the  -style
       option).   Arcs  are  created  with widget commands of the
       following form:
              pathName create arc x1 y1 x2 y2 ?option value option value ...?
              pathName create arc coordList ?option value option value ...?
       The arguments x1, y1, x2, and y2  or  coordList  give  the
       coordinates  of two diagonally opposite corners of a rect-
       angular region enclosing the oval that  defines  the  arc.
       After   the   coordinates  there  may  be  any  number  of
       option-value pairs, each of which sets one of the configu-
       ration  options  for  the  item.   These same option-value
       pairs may be used  in  itemconfigure  widget  commands  to
       change the item's configuration.
       The following standard options are supported by arcs:
              -dash
              -activedash
              -disableddash
              -dashoffset
              -fill
              -activefill
              -disabledfill
              -offset
              -outline
              -activeoutline
              -disabledoutline
              -outlinestipple
              -activeoutlinestipple
              -disabledoutlinestipple
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
              -width
              -activewidth
              -disabledwidth
       The following extra options are supported for arcs:

       -extent degrees
              Specifies the size of the angular range occupied by
              the arc.   The  arc's  range  extends  for  degrees
              degrees  counter-clockwise  from the starting angle
              given by the -start option.  Degrees may  be  nega-
              tive.  If it is greater than 360 or less than -360,
              then degrees modulo 360 is used as the extent.

       -start degrees
              Specifies the beginning of the angular range  occu-
              pied  by  the  arc.   Degrees  is given in units of
              degrees   measured   counter-clockwise   from   the
              3-o'clock  position;   it may be either positive or
              negative.

       -style type
              Specifies how to draw the arc.  If type is pieslice
              (the default) then the arc's region is defined by a
              section of the oval's perimeter plus two line  seg-
              ments,  one between the center of the oval and each
              end of the perimeter section.   If  type  is  chord
              then  the  arc's  region is defined by a section of
              the oval's perimeter plus  a  single  line  segment
              connecting the two end points of the perimeter sec-
              tion.  If type is arc then the  arc's  region  con-
              sists of a section of the perimeter alone.  In this
              last case the -fill option is ignored.


BITMAP ITEMS
       Items of type bitmap appear on the display as images  with
       two  colors,  foreground and background.  Bitmaps are cre-
       ated with widget commands of the following form:
              pathName create bitmap x y ?option value option value ...?
              pathName create bitmap coordList ?option value option value ...?
       The arguments x and y or coordList specify the coordinates
       of a point used to position the bitmap on the display (see
       the -anchor option  below  for  more  information  on  how
       bitmaps  are  displayed).  After the coordinates there may
       be any number of option-value pairs, each  of  which  sets
       one of the configuration options for the item.  These same
       option-value pairs may be  used  in  itemconfigure  widget
       commands to change the item's configuration.
       The following standard options are supported by bitmaps:
              -state
              -tags
       The following extra options are supported for bitmaps:

       -anchor anchorPos
              AnchorPos tells how to position the bitmap relative
              to the positioning point for the item;  it may have
              any  of  the  forms  accepted by Tk_GetAnchor.  For
              example, if anchorPos is center then the bitmap  is
              centered  on the point;  if anchorPos is n then the
              bitmap will be drawn so that its top  center  point
              is  at the positioning point.  This option defaults
              to center.

       -background color

       -activebackground bitmap

       -disabledbackground bitmap
              Specifies the color to use for each of the bitmap's
              '0'  valued  pixels  in its normal, active and dis-
              abled states.  Color may  have  any  of  the  forms
              accepted  by  Tk_GetColor.   If  this  option isn't
              specified, or  if  it  is  specified  as  an  empty
              string,  then nothing is displayed where the bitmap
              pixels are 0;  this produces a transparent  effect.
       -bitmap bitmap

       -activebitmap bitmap

       -disabledbitmap bitmap
              Specifies the bitmaps to display in the item in its
              normal, active and  disabled  states.   Bitmap  may
              have any of the forms accepted by Tk_GetBitmap.

       -foreground color

       -activeforeground bitmap

       -disabledforeground bitmap
              Specifies the color to use for each of the bitmap's
              '1' valued pixels in its normal,  active  and  dis-
              abled  states.   Color  may  have  any of the forms
              accepted by Tk_GetColor and defaults to black.


IMAGE ITEMS
       Items of type image are used to display images on  a  can-
       vas.   Images are created with widget commands of the fol-
       lowing form:
              pathName create image x y ?option value option value ...?
              pathName create image coordList ?option value option value ...?
       The arguments x and y or coordList specify the coordinates
       of  a point used to position the image on the display (see
       the -anchor option below for more information).  After the
       coordinates there may be any number of option-value pairs,
       each of which sets one of the  configuration  options  for
       the  item.   These  same option-value pairs may be used in
       itemconfigure widget commands to change the item's config-
       uration.
       The following standard options are supported by images:
              -state
              -tags
       The following extra options are supported for images:

       -anchor anchorPos
              AnchorPos  tells how to position the image relative
              to the positioning point for the item;  it may have
              any  of  the  forms  accepted by Tk_GetAnchor.  For
              example, if anchorPos is center then the  image  is
              centered  on the point;  if anchorPos is n then the
              image will be drawn so that its top center point is
              at  the positioning point.  This option defaults to
              center.

       -image name

       -activeimage name
       -disabledimage name
              Specifies the name of the images to display in  the
              item  in  is  normal,  active  and disabled states.
              This image must have been created  previously  with
              the image create command.


LINE ITEMS
       Items  of  type  line appear on the display as one or more
       connected line segments or  curves.   Line  items  support
       coordinate  indexing  operations  using  the canvas widget
       commands: dchars, index, insert.  Lines are  created  with
       widget commands of the following form:
              pathName create line x1 y1... xn yn ?option value option value ...?
              pathName create line coordList ?option value option value ...?
       The  arguments x1 through yn or coordList give the coordi-
       nates for a series of two or more points that  describe  a
       series  of connected line segments.  After the coordinates
       there may be any number of  option-value  pairs,  each  of
       which  sets one of the configuration options for the item.
       These same option-value pairs may be used in itemconfigure
       widget commands to change the item's configuration.
       The following standard options are supported by lines:
              -dash
              -activedash
              -disableddash
              -dashoffset
              -fill
              -activefill
              -disabledfill
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
              -width
              -activewidth
              -disabledwidth
       The following extra options are supported for lines:

       -arrow where
              Indicates whether or not arrowheads are to be drawn
              at one or both ends of the line.  Where  must  have
              one  of  the values none (for no arrowheads), first
              (for an arrowhead at the first point of the  line),
              last  (for  an  arrowhead  at the last point of the
              line), or both (for arrowheads at both ends).  This
              option defaults to none.

       -arrowshape shape
              This  option indicates how to draw arrowheads.  The
              shape argument must be a list with three  elements,
              each  specifying  a  distance  in  any of the forms
              described in the COORDINATES  section  above.   The
              first  element of the list gives the distance along
              the line from the neck of the arrowhead to its tip.
              The  second  element  gives  the distance along the
              line from the trailing points of the  arrowhead  to
              the  tip,  and the third element gives the distance
              from the outside edge of the line to  the  trailing
              points.   If  this  option  isn't specified then Tk
              picks a ``reasonable'' shape.

       -capstyle style
              Specifies the ways in which caps are to be drawn at
              the  endpoints  of the line.  Style may have any of
              the forms accepted by  Tk_GetCapStyle  (butt,  pro-
              jecting, or round).  If this option isn't specified
              then it defaults to  butt.   Where  arrowheads  are
              drawn the cap style is ignored.

       -joinstyle style
              Specifies  the ways in which joints are to be drawn
              at the vertices of the line.  Style may have any of
              the forms accepted by Tk_GetCapStyle (bevel, miter,
              or round).  If this option isn't specified then  it
              defaults  to  miter.  If the line only contains two
              points then this option is irrelevant.

       -smooth boolean
              Boolean must have one  of  the  forms  accepted  by
              Tk_GetBoolean.   It  indicates  whether  or not the
              line should be drawn as a curve.  If so,  the  line
              is  rendered  as  a  set  of parabolic splines: one
              spline is drawn for the first and second line  seg-
              ments,  one  for  the  second and third, and so on.
              Straight-line segments can be  generated  within  a
              curve  by duplicating the end-points of the desired
              line segment.

       -splinesteps number
              Specifies the  degree  of  smoothness  desired  for
              curves:  each spline will be approximated with num-
              ber line segments.  This option is  ignored  unless
              the -smooth option is true.


OVAL ITEMS
       Items  of  type oval appear as circular or oval regions on
       the display.  Each oval may have an outline,  a  fill,  or
       both.   Ovals are created with widget commands of the fol-
       lowing form:
              pathName create oval x1 y1 x2 y2 ?option value option value ...?
              pathName create oval coordList ?option value option value ...?
       The arguments x1, y1, x2, and y2  or  coordList  give  the
       coordinates  of two diagonally opposite corners of a rect-
       angular region enclosing the oval.  The oval will  include
       the  top  and left edges of the rectangle not the lower or
       right edges.  If the region is square then  the  resulting
       oval  is  circular;  otherwise  it  is elongated in shape.
       After  the  coordinates  there  may  be  any   number   of
       option-value pairs, each of which sets one of the configu-
       ration options for  the  item.   These  same  option-value
       pairs  may  be  used  in  itemconfigure widget commands to
       change the item's configuration.
       The following standard options are supported by ovals:
              -dash
              -activedash
              -disableddash
              -dashoffset
              -fill
              -activefill
              -disabledfill
              -offset
              -outline
              -activeoutline
              -disabledoutline
              -outlinestipple
              -activeoutlinestipple
              -disabledoutlinestipple
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
              -width
              -activewidth
              -disabledwidth


POLYGON ITEMS
       Items of type polygon appear as polygonal or curved filled
       regions  on the display.  Polygon items support coordinate
       indexing operations  using  the  canvas  widget  commands:
       dchars,  index,  insert.  Polygons are created with widget
       commands of the following form:
              pathName create polygon x1 y1 ... xn yn ?option value option value ...?
              pathName create polygon coordList ?option value option value ...?
       The arguments x1 through yn or coordList specify the coor-
       dinates  for  three  or more points that define a polygon.
       The first point should not be  repeated  as  the  last  to
       close the shape; Tk will automatically close the periphery
       between the first and last points.  After the  coordinates
       there  may  be  any  number of option-value pairs, each of
       which sets one of the configuration options for the  item.
       These same option-value pairs may be used in itemconfigure
       widget commands to change the item's configuration.
       The following standard options are supported by polygons:
              -dash
              -activedash
              -disableddash
              -dashoffset
              -fill
              -activefill
              -disabledfill
              -offset
              -outline
              -activeoutline
              -disabledoutline
              -outlinestipple
              -activeoutlinestipple
              -disabledoutlinestipple
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
              -width
              -activewidth
              -disabledwidth
       The following extra options are supported for polygons:

       -joinstyle style
              Specifies the ways in which joints are to be  drawn
              at the vertices of the outline.  Style may have any
              of the forms  accepted  by  Tk_GetCapStyle  (bevel,
              miter,  or  round).  If this option isn't specified
              then it defaults to miter.

       -smooth boolean
              Boolean must have one  of  the  forms  accepted  by
              Tk_GetBoolean It indicates whether or not the poly-
              gon should be drawn with a  curved  perimeter.   If
              so,  the  outline  of  the polygon becomes a set of
              parabolic splines, one spline  for  the  first  and
              second line segments, one for the second and third,
              and so on.  Straight-line segments can be generated
              in a smoothed polygon by duplicating the end-points
              of the desired line segment.

       -splinesteps number
              Specifies the  degree  of  smoothness  desired  for
              curves:  each spline will be approximated with num-
              ber line segments.  This option is  ignored  unless
              the -smooth option is true.

       Polygon items are different from other items such as rect-
       angles, ovals and arcs in that interior points are consid-
       ered  to be ``inside'' a polygon (e.g. for purposes of the
       find closest and find overlapping widget commands) even if
       it  is not filled.  For most other item types, an interior
       point is considered to be inside the item only if the item
       is  filled or if it has neither a fill nor an outline.  If
       you would like an unfilled polygon whose  interior  points
       are  not  considered  to be inside the polygon, use a line
       item instead.
RECTANGLE ITEMS
       Items of type rectangle appear as rectangular  regions  on
       the  display.  Each rectangle may have an outline, a fill,
       or both.  Rectangles are created with widget  commands  of
       the following form:
              pathName create rectangle x1 y1 x2 y2 ?option value option value ...?
              pathName create rectangle coordList ?option value option value ...?
       The  arguments  x1,  y1,  x2, and y2 or coordList give the
       coordinates of two  diagonally  opposite  corners  of  the
       rectangle  (the  rectangle will include its upper and left
       edges but not its lower or right edges).  After the  coor-
       dinates  there  may  be  any number of option-value pairs,
       each of which sets one of the  configuration  options  for
       the  item.   These  same option-value pairs may be used in
       itemconfigure widget commands to change the item's config-
       uration.
       The  following  standard  options are supported by rectan-
       gles:
              -dash
              -activedash
              -disableddash
              -dashoffset
              -fill
              -activefill
              -disabledfill
              -offset
              -outline
              -activeoutline
              -disabledoutline
              -outlinestipple
              -activeoutlinestipple
              -disabledoutlinestipple
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
              -width
              -activewidth
              -disabledwidth


TEXT ITEMS
       A text item displays a string of characters on the  screen
       in  one  or  more  lines.  Text items support indexing and
       selection, along with the  following  text-related  canvas
       widget  commands:   dchars, focus, icursor, index, insert,
       select.  Text items are created with  widget  commands  of
       the following form:
              pathName create text x y ?option value option value ...?
              pathName create text coordList ?option value option value ...?
       The arguments x and y or coordList specify the coordinates
       of a point used to position the text on the  display  (see
       the  options  below  for  more  information on how text is
       displayed).  After the coordinates there may be any number
       of  option-value pairs, each of which sets one of the con-
       figuration options for the item.  These same  option-value
       pairs  may  be  used  in  itemconfigure widget commands to
       change the item's configuration.
       The following  standard  options  are  supported  by  text
       items:
              -fill
              -activefill
              -disabledfill
              -stipple
              -activestipple
              -disabledstipple
              -state
              -tags
       The following extra options are supported for text items:

       -anchor anchorPos
              AnchorPos  tells  how to position the text relative
              to the positioning point for the text;  it may have
              any  of  the  forms  accepted by Tk_GetAnchor.  For
              example, if anchorPos is center then  the  text  is
              centered  on the point;  if anchorPos is n then the
              text will be drawn such that the top  center  point
              of the rectangular region occupied by the text will
              be at the positioning point.  This option  defaults
              to center.

       -font fontName
              Specifies the font to use for the text item.  Font-
              Name may be any string  acceptable  to  Tk_GetFont.
              If  this  option  isn't specified, it defaults to a
              system-dependent font.

       -justify how
              Specifies how to justify the text within its bound-
              ing  region.   How  must be one of the values left,
              right, or center.  This option will only matter  if
              the  text  is  displayed as multiple lines.  If the
              option is omitted, it defaults to left.

       -text string
              String specifies the characters to be displayed  in
              the  text  item.   Newline  characters  cause  line
              breaks.  The characters in the  item  may  also  be
              changed with the insert and delete widget commands.
              This option defaults to an empty string.

       -width lineLength
              Specifies a maximum line length for  the  text,  in
              any  of the forms described in the COORDINATES sec-
              tion above.  If this option is zero  (the  default)
              the text is broken into lines only at newline char-
              acters.  However, if this option is  non-zero  then
              any  line  that  would be longer than lineLength is
              broken just before a space character  to  make  the
              line  shorter than lineLength;  the space character
              is treated as if it were a newline character.


WINDOW ITEMS
       Items of type window cause a particular window to be  dis-
       played  at  a  given position on the canvas.  Window items
       are created with widget commands of the following form:
              pathName create window x y ?option value option value ...?
              pathName create window coordList ?option value option value ...?
       The arguments x and y or coordList specify the coordinates
       of a point used to position the window on the display (see
       the -anchor option  below  for  more  information  on  how
       bitmaps  are  displayed).  After the coordinates there may
       be any number of option-value pairs, each  of  which  sets
       one of the configuration options for the item.  These same
       option-value pairs may be  used  in  itemconfigure  widget
       commands to change the item's configuration.
       The  following  standard  options  are supported by window
       items:
              -state
              -tags
       The following  extra  options  are  supported  for  window
       items:

       -anchor anchorPos
              AnchorPos tells how to position the window relative
              to the positioning point for the item;  it may have
              any  of  the  forms  accepted by Tk_GetAnchor.  For
              example, if anchorPos is center then the window  is
              centered  on the point;  if anchorPos is n then the
              window will be drawn so that its top  center  point
              is  at the positioning point.  This option defaults
              to center.

       -height pixels
              Specifies the height to assign to the  item's  win-
              dow.  Pixels may have any of the forms described in
              the COORDINATES  section  above.   If  this  option
              isn't  specified, or if it is specified as an empty
              string, then the window is given whatever height it
              requests internally.

       -width pixels
              Specifies the width to assign to the item's window.
              Pixels may have any of the forms described  in  the
              COORDINATES  section  above.   If this option isn't
              specified, or  if  it  is  specified  as  an  empty
              string,  then the window is given whatever width it
              requests internally.
       -window pathName
              Specifies the window to associate with  this  item.
              The  window  specified by pathName must either be a
              child of the canvas  widget  or  a  child  of  some
              ancestor  of  the  canvas widget.  PathName may not
              refer to a top-level window.

       Note:  due to restrictions in the ways  that  windows  are
       managed,  it is not possible to draw other graphical items
       (such as lines and images) on top of window items.  A win-
       dow  item  always  obscures  any graphics that overlap it,
       regardless of their order in the display list.


APPLICATION-DEFINED ITEM TYPES
       It is possible for individual applications to  define  new
       item types for canvas widgets using C code.  See the docu-
       mentation for Tk_CreateItemType.


BINDINGS
       In the current implementation, new canvases are not  given
       any default behavior:  you'll have to execute explicit Tcl
       commands to give the canvas its behavior.


CREDITS
       Tk's canvas widget is a blatant ripoff of ideas from  Joel
       Bartlett's  ezd program.  Ezd provides structured graphics
       in a Scheme environment and preceded canvases by a year or
       two.   Its  simple  mechanisms  for  placing and animating
       graphical objects inspired the functions of canvases.


KEYWORDS
       canvas, widget
