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Canvas(3)	      User Contributed Perl Documentation	     Canvas(3)

NAME
       Tk::Canvas - Create and manipulate Canvas widgets

SYNOPSIS
       $canvas = $parent->Canvas(?options?);

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

WIDGET-SPECIFIC	OPTIONS
       Name:	 closeEnough
       Class:	 CloseEnough
       Switch:	 -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.

       Name:	 confine
       Class:	 Confine
       Switch:	 -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.

       Name:	 height
       Class:	 Height
       Switch:	 -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.

       Name:	 scrollRegion
       Class:	 ScrollRegion
       Switch:	 -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.

       Name:	 state
       Class:	 State
       Switch:	 -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 overrides	the default state.
	   Many	options	can take separate specifications 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.

       Name:	 width
       Class:	 width
       Switch:	 -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.

       Name:	 xScrollIncrement
       Class:	 ScrollIncrement
       Switch:	 -xscrollincrement
	   Specifies an	increment for horizontal scrolling, in any of the
	   usual forms permitted for screen distances.	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	multiple 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.

       Name:	 yScrollIncrement
       Class:	 ScrollIncrement
       Switch:	 -yscrollincrement
	   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.

DESCRIPTION
       The Canvas method creates a new window (given by	the $canvas 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 $canvas argument.	 At the	time this
       command is invoked, there must not exist	a window named $canvas,	but
       $canvas'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 manipulated (e.g. moved or re-colored) and
       callbacks may be	associated with	items in much the same way that	the
       bind method allows callbacks to be bound	to widgets.  For example, a
       particular callback may be associated with the <Button-1> event so that
       the callback is invoked whenever	button 1 is pressed with the mouse
       cursor over an item.  This means	that items in a	canvas can have
       behaviors defined by the	Callbacks 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	methods	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 methods; you must use the raise and lower Tk widget
       methods 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 methods,	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 subexpressions.  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 methods only operate on a single item at a time;  if tagOrId is
       specified in a way that names multiple items, then the normal behavior
       is for the methods is to	use the	first (lowest) of these	items in the
       display list that is suitable for the method.  Exceptions are noted in
       the method descriptions below.

COORDINATES
       All coordinates related to canvases are stored as floating-point
       numbers.	 Coordinates and distances are specified in screen units,
       which are floating-point	numbers	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.

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 coordinate system relative to the
       origin of the window using the xview and	yview methods;	this is
       typically used for scrolling.  Canvases do not support scaling or
       rotation	of the canvas coordinate system	relative to the	window
       coordinate system.

       Individual items	may be moved or	scaled using methods described below,
       but they	may not	be rotated.

INDICES
       Text items support the notion of	an index for identifying particular
       positions within	the item.

       Indices are used	for methods such as inserting text, deleting a range
       of characters, 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.

       In a similar fashion, line and polygon items support index for
       identifying, inserting and deleting subsets of their coordinates.
       Indices are used	for commands such as inserting or deleting 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
       indices 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	specified 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.	The Tcl	string form "@x,y" is
	   also	allowed.

DASH PATTERNS
       Many items support the notion of	an dash	pattern	for outlines.

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

       The second possible syntax is a character list containing only 5
       possible	characters [.,-_ ],  with the first 4 characters producing a
       segment of length 1 to 4, respectively, followed	by a transparent
       segment of length 2. The	space can be used repeatedly to	enlarge	the
       space between other line	elements by 1, and can not occur as the	first
       position	in the string.	The main difference of this syntax with	the
       previous	one 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.

       Some examples, for a line width of 2:

	-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]

       On systems where	only a limited set of dash patterns is available, the
       dash pattern will be displayed as the closest available dash pattern.
       For example, on Windows only the	first 4	of the above examples are
       available. The last 2 examples will be displayed	identically as the
       first one.

WIDGET METHODS
       The Canvas method creates a widget object.  This	object supports	the
       configure and cget methods described in Tk::options which can be	used
       to enquire and modify the options described above.  The widget also
       inherits	all the	methods	provided by the	generic	Tk::Widget class.

       The following additional	methods	are available for canvas widgets:

       $canvas->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 method 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 overlap 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 topmost 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.

       $canvas->bbox(tagOrId, ?tagOrId,	tagOrId, ...?)
	   Returns a list with four elements giving an approximate 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	matching items have
	   empty bounding boxes	(i.e. they have	nothing	to display) then an
	   empty string	is returned.

       $canvas->bind(tagOrId?, sequence? ?,callback?)
	   This	method associates callback with	all the	items given by tagOrId
	   such	that whenever the event	sequence given by sequence occurs for
	   one of the items the	callback will be invoked.  This	method is
	   similar to the bind method except that it operates on items in a
	   canvas rather than entire widgets.  See Tk::bind for	complete
	   details on the syntax of sequence and the substitutions performed
	   on callback 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 existing binding rather than
	   replacing it).  In this case	the return value is an empty string.
	   If callback is omitted then the method returns the callback
	   associated with tagOrId and sequence	(an error occurs if there is
	   no such binding).  If both callback and sequence are	omitted	then
	   the method returns a	list of	all the	sequences for which bindings
	   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 canvases 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 method below for more on
		   this).  If a	virtual	event is used in a binding, that
		   binding can trigger 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	multiple
		   matching bindings for a single tag, then only the most
		   specific binding is invoked.	 A continue in a callback
		   terminates that subroutine, and a break method terminates
		   that	subroutine and skips any remaining callbacks for the
		   event, just as for the bind method.

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

       $canvas->canvasx(screenx?, gridspacing?)
	   Given a window x-coordinate in the canvas screenx, this method
	   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.

       $canvas->canvasy(screeny, ?gridspacing?)
	   Given a window y-coordinate in the canvas screeny this method
	   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.

       $canvas->coords(tagOrId ?x0,y0 ...?)
	   Query or modify the coordinates that	define an item.	 If no
	   coordinates are specified, this method returns a list whose
	   elements are	the coordinates	of the item named by tagOrId.  If
	   coordinates are specified, then they	replace	the current
	   coordinates for the named item.  If tagOrId refers to multiple
	   items, then the first one in	the display list is used.

       $canvas->create(type, x,	y, ?x, y, ...?,	?option, value,	...?)
	   Create a new	item in	$canvas	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 syntax of this method.  This
	   method returns the id for the new item.

       $canvas->dchars(tagOrId,	first, ?last?)
	   For each item given by tagOrId, delete the characters, or
	   coordinates,	in the range given by first and	last, inclusive.  If
	   some	of the items given by tagOrId don't support 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).
	   within the item(s) as described in "INDICES"	above.	If last	is
	   omitted, it defaults	to first.  This	method returns an empty
	   string.

       $canvas->delete(?tagOrId, tagOrId, ...?)
	   Delete each of the items given by each tagOrId, and return an empty
	   string.

       $canvas->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 method.  If tagToDelete is omitted then it defaults to
	   tagOrId.  This method returns an empty string.

       $canvas->find(searchCommand, ?arg, arg, ...?)
	   This	method 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
	   method.  The	items are returned in stacking order, with the lowest
	   item	first.

       focus
       $canvas->focus(?tagOrId?)
	   Set the keyboard focus for the canvas widget	to the item given by
	   tagOrId.  If	tagOrId	refers to several items, then the focus	is set
	   to the first	such item in the display list that supports the
	   insertion 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 method 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
		   method) are totally independent: a given item doesn't
		   actually have the input focus unless	(a) its	canvas is the
		   focus window	and (b)	the item is the	focus item within the
		   canvas.  In most cases it is	advisable to follow the	focus
		   widget method with the CanvasFocus method to	set the	focus
		   window to the canvas	(if it wasn't there already).

       $canvas->gettags(tagOrId)
	   Return a list whose elements	are the	tags associated	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.

       $canvas->icursor(tagOrId, index)
	   Set the position of the insertion cursor for	the item(s) given by
	   tagOrId to just before the character	whose position is given	by
	   index.  If some or all of the items given by	tagOrId	don't support
	   an insertion	cursor then this method	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 method	focus,
	   below), but the cursor position may be set even when	the item
	   doesn't have	the focus.  This method	returns	an empty string.

       $canvas->index(tagOrId, index)
	   This	method 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	character,
	   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).

       $canvas->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
	   beforeThis.	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 coordinate sequence.  See	"INDICES" above	for
	   information about the forms allowed for beforeThis.	This method
	   returns an empty string.

       $canvas->itemcget(tagOrId, option)
	   Returns the current value of	the configuration option for the item
	   given by tagOrId whose name is option.  This	method is similar to
	   the cget method 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 method when the item was created.  If
	   tagOrId is a	tag that refers	to more	than one item, the first
	   (lowest) such item is used.

       $canvas->itemconfigure(tagOrId, ?option?, ?value?, ?option, value,
       ...?)
	   This	method is similar to the configure method 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 describing all of the available
	   options for the first item given by tagOrId (see Tk::options	for
	   information on the format of	this list).  If	option is specified
	   with	no value, then the method 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 method modifies
	   the given widget option(s) to have the given	value(s) in each of
	   the items given by tagOrId;	in this	case the method	returns	an
	   empty string.  The options and values are the same as those
	   permissible in the create method when the item(s) were created; see
	   the sections	describing individual item types below for details on
	   the legal options.

       $canvas->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 display list is used as the destination
	   location for	the moved items.  Note:	this method 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 methods of the	widget,	not the	raise and lower	methods	for
	   canvases.  This method returns an empty string.

       $canvas->move(tagOrId, xAmount, yAmount)
	   Move	each of	the items given	by tagOrId in the canvas 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 associated with the item.  This method	returns	an empty
	   string.

       $canvas->postscript(?option, value, option, value, ...?)
	   Generate a Postscript representation	for part or all	of the canvas.
	   If the -file	option is specified then the Postscript	is written to
	   a file and an empty string is returned;  otherwise the Postscript
	   is returned as the result of	the method.  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 created in Encapsulated
	   Postscript form using version 3.0 of	the Document Structuring
	   Conventions.	 Note: by default Postscript is	only generated for
	   information 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 method	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 following	options	are
	   supported:

	   -colormap =>	hashRef
		   HashRef must	be a reference to a hash variable or an
		   anonymous hash that specifies a color mapping to use	in the
		   Postscript.	Each value of the hash 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 a key in
		   the hash with the same name as the color.  If so, Tk	uses
		   the value of	the element as the Postscript method to	set
		   the color.  If this option hasn't been specified, or	if
		   there isn't a key in	hashRef	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 method instead
		   of being written to a file.

	   -fontmap => hashRef
		   HashRef must	be a reference to a hash variable or an
		   anonymous hash that specifies a font	mapping	to use in the
		   Postscript.	Each value of the hash must consist of an
		   array reference with	two elements, which are	the name and
		   point size of a Postscript font.  When outputting
		   Postscript commands for a particular	font, Tk checks	to see
		   if hashRef contains a value 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 canvas 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 positioning 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 factor from	-pagewidth  is used
		   (non-uniform	scaling	is not implemented).

	   -pagex => position
		   Position gives the x-coordinate of the positioning 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 positioning 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 output 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 canvas 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.

       $canvas->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 display list is used as the destination
	   location for	the moved items.  Note:	this method 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 widget	commands, not the raise	and lower methods for
	   canvases.  This method returns an empty string.

       $canvas->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	method returns an empty	string.

       $canvas->scan(option, args)
	   This	method is used to implement scanning on	canvases.  It has two
	   forms, depending on option:

	   $canvas->scanMark(x,	y)
		   Records x and y and the canvas's current view;  used	in
		   conjunction with later scanDragto method.  Typically	this
		   method 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.

	   $canvas->scanDragto(x, y, ?gain?.)
		   This	method computes	the difference between its x and y
		   arguments (which are	typically mouse	coordinates) and the x
		   and y arguments to the last scanMark	method for the widget.
		   It then adjusts the view by 10 times	the difference in
		   coordinates.	 This method is	typically associated 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.

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

	   $canvas->selectAdjust(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 selectTo method calls.  If the
		   selection isn't currently in	tagOrId	then this method
		   behaves the same as the selectTo widget method.  Returns an
		   empty string.

	   $canvas->selectClear
		   Clear the selection if it is	in this	widget.	 If the
		   selection isn't in this widget then the method has no
		   effect.  Returns an empty string.

	   $canvas->selectFrom(tagOrId,	index)
		   Set the selection anchor point for the widget to be just
		   before the character	given by index in the item given by
		   tagOrId.  This method doesn't change	the selection;	it
		   just	sets the fixed end of the selection for	future
		   selectTo method calls.  Returns an empty string.

	   $canvas->selectItem
		   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.

	   $canvas->selectTo(tagOrId, index)
		   Set the selection to	consist	of those characters 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 selectAdjust
		   or selectFrom method	calls 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.

       $canvas->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.

       $canvas->xview(?args?)
	   This	method is used to query	and change the horizontal position of
	   the information displayed in	the canvas's window.  It can take any
	   of the following forms:

	   $canvas->xview
		   Returns a list containing two elements.  Each element is a
		   real	fraction between 0 and 1;  together they describe the
		   horizontal 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	middle
		   40% is visible in the window, and 40% of the	canvas is off-
		   screen to the right.	 These are the same values passed to
		   scrollbars via the -xscrollcommand option.

	   $canvas->xviewMoveto(fraction)
		   Adjusts the view in the window so that fraction of the
		   total width of the canvas is	off-screen to the left.
		   Fraction must be a fraction between 0 and 1.

	   $canvas->xviewScroll(number,	what)
		   This	method 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 window'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.

       $canvas->yview(?args?)
	   This	method is used to query	and change the vertical	position of
	   the information displayed in	the canvas's window.  It can take any
	   of the following forms:

	   $canvas->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
		   -scrollregion option) is visible in the window.  These are
		   the same values passed to scrollbars	via the
		   -yscrollcommand option.

	   $canvas->yviewMoveto(fraction)
		   Adjusts the view in the window so that fraction of the
		   canvas's area is off-screen to the top.  Fraction is	a
		   fraction between 0 and 1.

	   $canvas->yviewScroll(number,	what)
		   This	method 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 window'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 characterized	by two things: first,
       the form	of the create method 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 methods.  Most	items
       don't support indexing or selection or the methods 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 polygons the
       indexing	facility is used to manipulate the coordinates of the item.

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	methods	of the
       following form:

	$canvas->createArc(x1, y1, x2, y2, ?option, value, option, value, ...?)

       The arguments x1, y1, x2, and y2	give the coordinates of	two diagonally
       opposite	corners	of a rectangular 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 configuration options
       for the item.  These same option-value pairs may	be used	in
       itemconfigure methods to	change the item's configuration.  The
       following options are supported for arcs:

       -dash =>	pattern
       -activedash => pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, the
	   active state, and the disabled state	of an arc item.	 pattern may
	   have	any of the forms accepted by Tk_GetDash.  If the dash options
	   are omitted then the	default	is a solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -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
	   negative.  If it is greater than 360	or less	than -360, then
	   degrees modulo 360 is used as the extent.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the arc region 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 arc will not	be filled.

       -outline	=> color
       -activeoutline => color
       -disabledoutline	=> color
	   This	option specifies the color that	should be used to draw the
	   outline of the arc 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 undef then no
	   outline is drawn for	the arc.

       -outlinestipple => bitmap
       -activeoutlinestipple =>	bitmap
       -disabledoutlinestipple => bitmap
	   This	option specifies stipple patterns that should be used to draw
	   the outline of the arc in its normal, active	and disabled states.
	   Indicates that the outline for the arc 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.

       -start => degrees
	   Specifies the beginning of the angular range	occupied 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.

       -state => state
	   Modifies the	state of the arc item where state may be set to	one
	   of: normal, disabled, hidden	or "". If set to empty,	the state of
	   the canvas itself is	used. An arc item may also be in the "active"
	   state if the	mouse is currently over	it.  Many options can take
	   separate specifications in normal, active and disabled states such
	   that	the appearance of the item can be different in each state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the arc 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 filling is done in a solid fashion.

       -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 segments, 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 section.  If type is arc then the arc's region consists
	   of a	section	of the perimeter alone.	 In this last case the -fill
	   option is ignored.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the arc item
	   is updated on the screen.

       -width => outlineWidth
       -activewidth => outlineWidth
       -disabledwidth => outlineWidth
	   Specifies the width of the outline to be drawn around the arc'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	undef then
	   this	option has no effect.  Wide outlines will be drawn centered on
	   the edges of	the arc's region.  This	option defaults	to 1.0.

BITMAP ITEMS
       Items of	type bitmap appear on the display as images with two colors,
       foreground and background.  Bitmaps are created with methods of the
       following form:

	$canvas->createBitmap(x, y, ?option, value, option, value, ...?)

       The arguments x and y 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 methods to change the	item's
       configuration.  The following 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 => color
       -disabledbackground => color
	   Specifies the color to use for each of the bitmap's '0' valued
	   pixels in its normal, active	and disabled states.  Color may	have
	   any of the forms accepted by	Tk_GetColor.  If this option isn't
	   specified, or if it is specified as undef, 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.	All bitmaps must have the same width and
	   height.  Bitmap may have any	of the forms accepted by Tk_GetBitmap.

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

       -state => state
	   Modifies the	state of the bitmap item where state may be set	to one
	   of: normal, disabled, or hidden.  An	bitmap item may	also be	in the
	   "active" state if the mouse is currently over it.  Many options can
	   take	separate specifications	in normal, active and disabled states
	   such	that the appearance of the item	can be different in each
	   state.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the bitmap
	   item	is updated on the screen.

GRID ITEMS
       Items of	type grid are intended for producing a visual reference	for
       interpreting other items. They can be drawn as either lines (with dash
       style) or as rectangular	"dots" at each grid point.

       Items of	type grid are unlike other items they always cover the whole
       of the canvas, but are never enclosed by	nor overlap any	area and are
       not near	any point. That	is they	are intended to	be always visible but
       not "pickable", as such they do support the "active" state.  They are
       like other items	in that: multiple grids	are permitted, they can	be
       raised and lowered relative to other items, they	can be moved and
       scaled. As yet grids do not appear in PostScript	output.

       Grids have outline like configure options. Grids	are created with
       methods of the following	form:

	$canvas->createGrid(x1,	y1, x2,	y2, ?option, value, option, value, ...?)

       The arguments x1, y1 give the origin of the grid. x2, and y2 give the
       coordinates of the next grid point in their respective directions.
       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 methods to
       change the item's configuration.

       The following options are supported for grids:

       -lines => boolean
	   If -lines is	set to a true value then lines are drawn for both X
	   and Y grids in the style determined by -dash. Otherwise retangular
	   "dots" are drawn at each grid point.

       -dash =>	pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, and the
	   disabled state of a grid item.  pattern may have any	of the forms
	   accepted by Tk_GetDash.  If the dash	options	are omitted then the
	   default is a	solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -color => color
       -disabledcolor => color
	   This	option specifies the color that	should be used to draw the
	   outline of the grid in its normal and disabled states.  Color may
	   have	any of the forms accepted by Tk_GetColor.  This	option
	   defaults to black.  If color	is undef then no grid will be drawn.

       -stipple	=> bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to draw
	   the outline of the rectangle	in its normal and disabled states.
	   bitmap specifies the	stipple	pattern	to use,	in any of the forms
	   accepted by Tk_GetBitmap.  If bitmap	is an empty string (the
	   default), then the outline is drawn in a solid fashion.

       -state => state
	   Modifies the	state of the rectangle item where state	may be set to
	   one of: normal, disabled, or	hidden.	Many options can take separate
	   specifications in normal and	disabled states	such that the
	   appearance of the item can be different in each state.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the grid
	   item	is updated on the screen.

       -width => outlineWidth
       -disabledwidth => outlineWidth
	   Specifies the width of the lines drawn by the grid or the size (in
	   both	X and Y) of the	dots, in its normal and	disabled states.  This
	   option defaults to 1.0.

IMAGE ITEMS
       Items of	type image are used to display images on a canvas.  Images are
       created with methods of the following form:

	$canvas->createImage(x,	y, ?option, value, option, value, ...?)

       The arguments x and y 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 methods to	change the item's configuration.  The
       following 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, see Tk::Image.

       -state => state
	   Modifies the	state of the image item	where state may	be set to one
	   of: normal, disabled, or hidden.  An	image item may also be in the
	   "active" state if the mouse is currently over it.  Many options can
	   take	separate specifications	in normal, active and disabled states
	   such	that the appearance of the item	can be different in each
	   state.

       -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;
	   it may be an	empty list.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the image
	   item	is updated on the screen.

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	methods: dchars, index,	insert.	 Lines are created
       with methods of the following form:

	$canvas->createLine(x1,	y1..., xn, yn, ?option,	value, option, value, ...?)

       The arguments x1	through	yn give	the coordinates	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 methods to change the
       item's configuration.  The following 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, projecting, or	round).	 If this option	isn't
	   specified then it defaults to butt.	Where arrowheads are drawn the
	   cap style is	ignored.

       -dash =>	pattern
       -activedash => pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, the
	   active state, and the disabled state	of a line item.	 pattern may
	   have	any of the forms accepted by Tk_GetDash.  If the dash options
	   are omitted then the	default	is a solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the line in its normal,
	   active, and disabled	states.	 Color may have	any of the forms
	   acceptable to Tk_GetColor.  It may also be undef, in	which case the
	   line	will be	transparent.  This option defaults to black.

       -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 segments, 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 number line segments.  This option	is
	   ignored unless the -smooth option is	true.

       -state => state
	   Modifies the	state of the line item where state may be set to one
	   of: normal, disabled, or hidden.  A line item may also be in	the
	   "active" state if the mouse is currently over it.  Many options can
	   take	separate specifications	in normal, active and disabled states
	   such	that the appearance of the item	can be different in each
	   state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the line	in its normal, active and disabled states.  bitmap
	   specifies the stipple pattern to use, in any	of the forms accepted
	   by Tk_GetBitmap.  If	bitmap is an empty string (the default), then
	   filling is done in a	solid fashion.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the line
	   item	is updated on the screen.

       -width => lineWidth
       -activewidth => lineWidth
       -disabledwidth => lineWidth
	   Specifies the width of the line in its normal, active and disabled
	   states.  lineWidth may be in	any of the forms described in the
	   "COORDINATES" section above.

	   Wide	lines will be drawn centered on	the path specified by the
	   points.  If this option isn't specified then	it defaults to 1.0.

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
       methods of the following	form:

	$canvas->createOval(x1,	y1, x2,	y2, ?option, value, option, value, ...?)

       The arguments x1, y1, x2, and y2	give the coordinates of	two diagonally
       opposite	corners	of a rectangular 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 configuration options for	the item.  These same option-value
       pairs may be used in itemconfigure methods to change the	item's
       configuration.  The following options are supported for ovals:

       -dash =>	pattern
       -activedash => pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, the
	   active state, and the disabled state	of an oval item.  pattern may
	   have	any of the forms accepted by Tk_GetDash.  If the dash options
	   are omitted then the	default	is a solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the oval in its normal,
	   active, and disabled	states.	 Color may have	any of the forms
	   accepted by Tk_GetColor.  If	color is undef (the default), then
	   then	the oval will not be filled.

       -outline	=> color
       -activeoutline => color
       -disabledoutline	=> color
	   This	option specifies the color that	should be used to draw the
	   outline of the oval 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 undef	then no	outline	will
	   be drawn for	the oval.

       -outlinestipple => bitmap
       -activeoutlinestipple =>	bitmap
       -disabledoutlinestipple => bitmap
	   This	option specifies stipple patterns that should be used to draw
	   the outline of the oval 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 -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.

       -state => state
	   Modifies the	state of the oval item where state may be set to one
	   of: normal, disabled, or hidden.  An	oval item may also be in the
	   "active" state if the mouse is currently over it.  Many options can
	   take	separate specifications	in normal, active and disabled states
	   such	that the appearance of the item	can be different in each
	   state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the oval	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 filling is done in a solid fashion.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the oval
	   item	is updated on the screen.

       -width => outlineWidth
       -activewidth => outlineWidth
       -disabledwidth => outlineWidth
	   Specifies the width of the outline to be drawn around the oval, in
	   its normal, active and disabled states.  outlineWidth specifies the
	   width of the	outline	to be drawn around the oval, in	any of the
	   forms described in the "COORDINATES"	section	above.

	   If the -outline option hasn't been specified	then this option has
	   no effect.  Wide outlines are drawn centered	on the oval path
	   defined by x1, y1, x2, and y2.  This	option defaults	to 1.0.

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	methods: dchars, index,	insert.	 Polygons are created
       with methods of the following form:

	$canvas->createPolygon(x1, y1, ..., xn,	yn, ?option, value, option, value, ...?)

       The arguments x1	through	yn specify the coordinates for three or	more
       points that define a closed polygon.  The first and last	points may be
       the same;  whether they are or not, Tk will draw	the polygon as a
       closed polygon.	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 methods to	change the item's configuration.  The
       following options are supported for polygons:

       -dash =>	pattern
       -activedash => pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, the
	   active state, and the disabled state	of an polygon item.  pattern
	   may have any	of the forms accepted by Tk_GetDash.  If the dash
	   options are omitted then the	default	is a solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the polygon in its normal,
	   active, and disabled	states.	 Color may have	any of the forms
	   acceptable to Tk_GetColor.  If color	is undef then the polygon will
	   be transparent.  This option	defaults to black.

       -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.

       -outline	=> color
       -activeoutline => color
       -disabledoutline	=> color
	   This	option specifies the color that	should be used to draw the
	   outline of the polygon in its normal, active	and disabled states.
	   Color may have any of the forms accepted by Tk_GetColor.  If	color
	   is undef then no outline will be drawn for the polygon.  This
	   option defaults to undef (no	outline).

       -outlinestipple => bitmap
       -activeoutlinestipple =>	bitmap
       -disabledoutlinestipple => bitmap
	   This	option specifies stipple patterns that should be used to draw
	   the outline of the polygon 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 -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.

       -smooth => boolean
	   Boolean must	have one of the	forms accepted by Tk_GetBoolean	It
	   indicates whether or	not the	polygon	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 number line segments.  This option	is
	   ignored unless the -smooth option is	true.

       -state => state
	   Modifies the	state of the polygon item where	state may be set to
	   one of: normal, disabled, or	hidden.	 A polygon item	may also be in
	   the "active"	state if the mouse is currently	over it.  Many options
	   can take separate specifications in normal, active and disabled
	   states such that the	appearance of the item can be different	in
	   each	state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the polygon in its normal, active and disabled states.  bitmap
	   specifies the stipple pattern to use, in any	of the forms accepted
	   by Tk_GetBitmap.  If	bitmap is an empty string (the default), then
	   filling is done in a	solid fashion.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the polygon
	   item	is updated on the screen.

       -width => outlineWidth
       -activewidth => outlineWidth
       -disabledwidth => outlineWidth
       Specifies the width of the outline to be	drawn around
	   the polygon,	in its normal, active and disabled states.
	   outlineWidth	may be in any of the forms described in	the
	   COORDINATES section above.  OutlineWidth specifies the width	of the
	   outline to be drawn around the polygon, in any of the forms
	   described in	the "COORDINATES" section above.  If the -outline
	   option hasn't been specified	then this option has no	effect.	 This
	   option defaults to 1.0.

	   Polygon items are different from other items	such as	rectangles,
	   ovals and arcs in that interior points are considered to be
	   ``inside'' a	polygon	(e.g. for purposes of the find closest and
	   find	overlapping methods) 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 methods of the following form:

	$canvas->createRectangle(x1, y1, x2, y2, ?option, value, option, value,	...?)

       The arguments x1, y1, x2, and y2	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
       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 methods to change the
       item's configuration.  The following options are	supported for
       rectangles:

       -dash =>	pattern
       -activedash => pattern
       -disableddash =>	pattern
	   This	option specifies dash patterns for the normal state, the
	   active state, and the disabled state	of a rectangle item.  pattern
	   may have any	of the forms accepted by Tk_GetDash.  If the dash
	   options are omitted then the	default	is a solid outline.

       -dashoffset => offset
	   The starting	offset into the	pattern	provided by the	-dash option.
	   -dashoffset is ignored if there is no -dash pattern.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the rectangle	in its normal,
	   active, and disabled	states.	 Color may be specified	in any of the
	   forms accepted by Tk_GetColor.  If color is undef (the default),
	   then	the rectangle will not be filled.

       -outline	=> color
       -activeoutline => color
       -disabledoutline	=> color
	   This	option specifies the color that	should be used to draw the
	   outline of the rectangle 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 undef	then no	outline	will
	   be drawn for	the rectangle.

       -outlinestipple => bitmap
       -activeoutlinestipple =>	bitmap
       -disabledoutlinestipple => bitmap
	   This	option specifies stipple patterns that should be used to draw
	   the outline of the rectangle	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 -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.

       -state => state
	   Modifies the	state of the rectangle item where state	may be set to
	   one of: normal, disabled, or	hidden.	 A rectangle item may also be
	   in the "active" state if the	mouse is currently over	it.  Many
	   options can take separate specifications in normal, active and
	   disabled states such	that the appearance of the item	can be
	   different in	each state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the rectangle 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 filling is done in a solid fashion.

       -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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the
	   rectangle item is updated on	the screen.

       -width => outlineWidth
       -activewidth => outlineWidth
       -disabledwidth => outlineWidth
	   Specifies the width of the outline to be drawn around the
	   rectangle, in its normal, active and	disabled states.  OutlineWidth
	   specifies the width of the outline to be drawn around the
	   rectangle, in any of	the forms described in the "COORDINATES"
	   section above.

	   If the -outline option hasn't been specified	then this option has
	   no effect.  Wide outlines are drawn centered	on the rectangular
	   path	defined	by x1, y1, x2, and y2.	This option defaults to	1.0.

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 methods:  dchars, focus, icursor, index,
       insert, select.	Text items are created with methods of the following
       form:

	$canvas->createText(x, y, ?option, value, option, value, ...?)

       The arguments x and y 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
       configuration options for the item.  These same option-value pairs may
       be used in itemconfigure	methods	to change the item's configuration.
       The following 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.

       -fill =>	color
       -activefill => color
       -disabledfill =>	color
	   Specifies the color to be used to fill the text in its normal,
	   active, and disabled	states.	 Color may have	any of the forms
	   accepted by Tk_GetColor.  If	color is undef then the	text will be
	   transparent.	 If this option	isn't specified	then it	defaults to
	   black.

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

       -justify	=> how
	   Specifies how to justify the	text within its	bounding 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.

       -state => state
	   Modifies the	state of the text item where state may be set to one
	   of: normal, disabled, or hidden.  A text item may also be in	the
	   "active" state if the mouse is currently over it.  Many options can
	   take	separate specifications	in normal, active and disabled states
	   such	that the appearance of the item	can be different in each
	   state.

       -stipple	=> bitmap
       -activestipple => bitmap
       -disabledstipple	=> bitmap
	   This	option specifies stipple patterns that should be used to fill
	   the the text	in its normal, active and disabled states.  bitmap
	   specifies the stipple pattern to use, in any	of the forms accepted
	   by Tk_GetBitmap.  If	bitmap is an empty string (the default)	then
	   the text is drawn in	a solid	fashion.

       -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.

       -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 methods.  This
	   option defaults to an empty string.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the text
	   item	is updated on the screen.

       -width => lineLength
	   Specifies a maximum line length for the text, in any	of the forms
	   described in	the "COORDINATES" section above.  If this option is
	   zero	(the default) the text is broken into lines only at newline
	   characters.	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 displayed at a
       given position on the canvas.  Window items are created with methods of
       the following form:

       A A A A $canvas->createWindow(x,	y?, -option=>value, -option=>value,
       ...?)

       The arguments x and y 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 method to change the item's
       configuration.  The following 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	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 height it requests
	   internally.

       -state => state
	   Modifies the	state of the window item where state may be set	to one
	   of: 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.

       -updatecommand => command
	   Specifies a callback	that is	to be executed every time the window
	   item	is updated on the screen.

       -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 => $widget
	   Specifies the window	to associate with this item.  The window
	   specified by	$widget	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 window 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 documentation for
       Tk_CreateItemType.

BINDINGS
       Canvas has default bindings to allow scrolling if necessary: <Up>,
       <Down>, <Left> and <Right> (and their <Control-*> counter parts).
       Further <Proir>,	<Next>,	<Home> and <End>.  These bindings allow	you to
       navigate	the same way as	in other widgets that can scroll.

Perl/Tk	Methods
       The following methods are added as perl code:

       $canvas->get_corners
	   Returns the bounding	box in Canvas coordinates of the visible
	   portion of the Canvas. (Written by Slaven Rezic.)

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

perl v5.24.1			  2013-11-15			     Canvas(3)

NAME | SYNOPSIS | STANDARD OPTIONS | WIDGET-SPECIFIC OPTIONS | DESCRIPTION | DISPLAY LIST | ITEM IDS AND TAGS | COORDINATES | TRANSFORMATIONS | INDICES | DASH PATTERNS | WIDGET METHODS | OVERVIEW OF ITEM TYPES | ARC ITEMS | BITMAP ITEMS | GRID ITEMS | IMAGE ITEMS | LINE ITEMS | OVAL ITEMS | POLYGON ITEMS | RECTANGLE ITEMS | TEXT ITEMS | WINDOW ITEMS | APPLICATION-DEFINED ITEM TYPES | BINDINGS | Perl/Tk Methods | CREDITS | KEYWORDS

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