[Emacs-diffs] Changes to emacs/lispref/display.texi [emacs-unicode-2]

[Miles Bader]

Index: emacs/lispref/display.texi
diff -c emacs/lispref/display.texi:1.95.2.5 emacs/lispref/display.texi:1.95.2.6
*** emacs/lispref/display.texi:1.95.2.5 Fri Jul 23 04:30:39 2004
--- emacs/lispref/display.texi  Sat Sep 25 12:05:24 2004
***************
*** 25,31 ****
--- 25,34 ----
  * Faces::               A face defines a graphics style for text characters:
                            font, colors, etc.
  * Fringes::             Controlling window fringes.
+ * Fringe Bitmaps::      Displaying bitmaps in the window fringes.
+ * Customizing Bitmaps:: Specifying your own bitmaps to use in the fringes.
  * Scroll Bars::         Controlling vertical scroll bars.
+ * Pointer Shape::       Controlling the mouse pointer shape.
  * Display Property::    Enabling special display features.
  * Images::              Displaying images in Emacs buffers.
  * Buttons::             Adding clickable buttons to Emacs buffers.
***************
*** 1486,1492 ****
  
  @item fringe
  @kindex fringe @r{(face name)}
! This face controls the colors of window fringes, the thin areas on
  either side that are used to display continuation and truncation glyphs.
  
  @item minibuffer-prompt
--- 1489,1495 ----
  
  @item fringe
  @kindex fringe @r{(face name)}
! This face controls the default colors of window fringes, the thin areas on
  either side that are used to display continuation and truncation glyphs.
  
  @item minibuffer-prompt
***************
*** 2560,2566 ****
  
  @defvar fringes-outside-margins
  If the value is address@hidden, the frames appear outside
! the display margins. 
  @end defvar
  
  @defvar left-fringe-width
--- 2563,2569 ----
  
  @defvar fringes-outside-margins
  If the value is address@hidden, the frames appear outside
! the display margins.
  @end defvar
  
  @defvar left-fringe-width
***************
*** 2596,2601 ****
--- 2599,2789 ----
  @var{right-width} @var{frames-outside-margins})}.
  @end defun
  
+ @defvar overflow-newline-into-fringe
+ If this is address@hidden, lines exactly as wide as the window (not
+ counting the final newline character) are not continued.  Instead,
+ when point is at the end of the line, the cursor appears in the right
+ fringe.
+ @end defvar
+ 
+ @node Fringe Bitmaps
+ @section Fringe Bitmaps
+ @cindex fringe bitmaps
+ @cindex bitmaps, fringe
+ 
+   The @dfn{fringe bitmaps} are tiny icons Emacs displays in the window
+ fringe (on a graphic display) to indicate truncated or continued
+ lines, buffer boundaries, overlay arrow, etc.  The fringe bitmaps are
+ shared by all frames and windows.  You can redefine the built-in
+ fringe bitmaps, and you can define new fringe bitmaps.  However, Emacs
+ can handle only 255 different fringe bitmaps.
+ 
+   The way to display a bitmap in the left or right fringes for a given
+ line in a window is by specifying the @code{display} property for one
+ of the characters that appears in it.  Use a display specification of
+ the form @code{(left-fringe @var{bitmap} address@hidden)} or
+ @code{(right-fringe @var{bitmap} address@hidden)} (@pxref{Display
+ Property}).  Here, @var{bitmap} is an integer identifying the bitmap
+ you want, and @var{face} (which is optional) is the name of the face
+ whose colors should be used for displaying the bitmap.
+ @c ??? Shouldn't the symbol name be used?
+ 
+   These are the symbols identify the standard fringe bitmaps.
+ Evaluate @code{(require 'fringe)} to define them.  Each symbol's
+ value is an integer that identifies the corresponding bitmap.
+ 
+ @table @asis
+ @item Truncation and continuation line bitmaps:
+ @code{left-truncation-fringe-bitmap},
+ @code{right-truncation-fringe-bitmap},
+ @code{continued-line-fringe-bitmap},
+ @code{continuation-line-fringe-bitmap}.
+ 
+ @item Buffer indication bitmaps:
+ @code{up-arrow-fringe-bitmap},
+ @code{down-arrow-fringe-bitmap},
+ @code{top-left-angle-fringe-bitmap},
+ @code{top-right-angle-fringe-bitmap},
+ @code{bottom-left-angle-fringe-bitmap},
+ @code{bottom-right-angle-fringe-bitmap},
+ @code{left-bracket-fringe-bitmap},
+ @code{right-bracket-fringe-bitmap}.
+ 
+ @item Empty line indication bitmap:
+ @code{empty-line-fringe-bitmap}.
+ 
+ @item Overlay arrow bitmap:
+ @code{overlay-arrow-fringe-bitmap}.
+ 
+ @item Bitmaps for displaying the cursor in right fringe:
+ @code{filled-box-cursor-fringe-bitmap},
+ @code{hollow-box-cursor-fringe-bitmap},
+ @code{hollow-square-fringe-bitmap}, @code{bar-cursor-fringe-bitmap},
+ @code{hbar-cursor-fringe-bitmap}.
+ 
+ @item Value indicating that no fringe bitmap is present:
+ @code{no-fringe-bitmap}.
+ @c ??? I don't understand what that means.
+ @c ??? Where would you find that value?
+ 
+ @item Value indicating a reference to an undefined bitmap:
+ @code{undef-fringe-bitmap}.
+ @c ??? I don't understand what that means.
+ @c ??? Where would you find that value?
+ @end table
+ 
+ @defun fringe-bitmaps-at-pos &optional pos window
+ This function returns the fringe bitmaps of the display line
+ containing position @var{pos} in window @var{window}.  The return
+ value has the form @code{(@var{left} . @var{right})}, where @var{left}
+ is a list of fringe bitmap numbers for left fringe, and @var{right} is
+ similar for the right fringe.  These bitmap numbers are usually values
+ of symbols such as the ones listed above.
+ 
+ @c ??? Why not return a list of symbols that identify the bitmaps?
+ @c ??? This is Lisp, not C.
+ 
+ The value is @code{nil} if @var{pos} is not visible in @var{window}.
+ If @var{window} is @code{nil}, that stands for the selected window.
+ If @var{pos} is @code{nil}, that stands for the value of point in
+ @var{window}.
+ @end defun
+ 
+ @node Customizing Bitmaps
+ @section Customizing Fringe Bitmaps
+ 
+ @c ??? Why not pass a symbol as the first argument
+ @c ??? and define that symbol.  It would be cleaner.
+ 
+ @defun define-fringe-bitmap bits &optional height width align bitmap
+ This function defines a new fringe bitmap, or replaces an existing
+ bitmap.
+ 
+ The argument @var{bits} specifies the image to use.  It should be
+ either a string or a vector of integers, where each element (an
+ integer) corresponds to one row of the bitmap.  Each bit of an integer
+ corresponds to one pixel of the bitmap.
+ @c ??? Is the low bit the leftmost or the rightmost bit?
+ 
+ The height is normally the length of @var{bits}.  However, you
+ can specify a different height with address@hidden @var{height}.  The width
+ is normally 8, but you can specify a different width with address@hidden
+ @var{width}.  The width must be an integer between 1 and 16.
+ 
+ The argument @var{align} specifies the positioning of the bitmap
+ relative to the range of rows where it is used; the default is to
+ center the bitmap.  The allowed values are @code{top}, @code{center},
+ or @code{bottom}.
+ 
+ The @var{align} argument may also be a list @code{(@var{align}
+ @var{periodic})} where @var{align} is intepreted as described above.
+ If @var{periodic} is address@hidden, it specifies that the rows in
+ @code{bits} should be repeated enough times to reach the specified
+ height.
+ 
+ The argument @var{bitmap} specifies an existing bitmap to redefine.
+ You should pass the value of the symbol that identifies the bitmap.
+ 
+ The return value on success is an integer identifying the new bitmap.
+ You should save that integer in a variable so it can be used to select
+ this bitmap.  The value can also be @code{nil} of there are no more
+ free bitmap slots.
+ @c ??? Why not signal an error?  That would be cleaner.
+ @end defun
+ 
+ @defun destroy-fringe-bitmap bitmap
+ This function destroy the fringe bitmap identified by @var{bitmap}.
+ If @var{bitmap} identifies a standard fringe bitmap, it actually
+ restores the standard definition of that bitmap, instead of
+ eliminating it entirely.
+ @end defun
+ 
+ @defun set-fringe-bitmap-face bitmap &optional face
+ This sets the face for the fringe bitmap @var{bitmap} to @var{face}.
+ If @var{face} is @code{nil}, it selects the @code{fringe} face.  The
+ bitmap's face controls the color to draw it in.
+ 
+ The face you use here should be derived from @code{fringe}, and should
+ specify only the foreground color.
+ @end defun
+ 
+ @defvar indicate-buffer-boundaries
+ This buffer-local variable controls how the buffer boundaries and
+ window scrolling are indicated in the window fringes.
+ 
+ Emacs can indicate the buffer boundaries---that is, the first and last
+ line in the buffer---with angle icons when they appear on the screen.
+ In addition, Emacs can display an up-arrow in the fringe to show
+ that there is text above the screen, and a down-arrow to show
+ there is text below the screen.
+ 
+ There are four kinds of basic values:
+ 
+ @table @asis
+ @item @code{nil}
+ Don't display the icons.
+ @item @code{left}
+ Display them in the left fringe.
+ @item @code{right}
+ Display them in the right fringe.
+ @item @var{anything-else}
+ Display the icon at the top of the window top in the left fringe, and other
+ in the right fringe.
+ @end table
+ 
+ If value is a cons @code{(@var{angles} . @var{arrows})}, @var{angles}
+ controls the angle icons, and @var{arrows} controls the arrows.  Both
+ @var{angles} and @var{arrows} work according to the table above.
+ Thus, @code{(t .  right)} places the top angle icon in the left
+ fringe, the bottom angle icon in the right fringe, and both arrows in
+ the right fringe.
+ @end defvar
+ 
+ @defvar default-indicate-buffer-boundaries
+ The value of this variable is the default value for
+ @code{indicate-buffer-boundaries} in buffers that do not override it.
+ @end defvar
+ 
  @node Scroll Bars
  @section Scroll Bars
  
***************
*** 2609,2626 ****
  @code{set-window-scroll-bars} to specify what to do for a specific window:
  
  @defun set-window-scroll-bars window width &optional vertical-type 
horizontal-type
! Set width and type of scroll bars of window @var{window}.  
! If @var{window} is @code{nil}, the selected window is used.
  @var{width} specifies the scroll bar width in pixels (@code{nil} means
! use whatever is specified for width for the frame).
! @var{vertical-type} specifies whether to have a vertical scroll bar
! and, if so, where.  The possible values are @code{left}, @code{right}
! and @code{nil}, just like the values of the
! @code{vertical-scroll-bars} frame parameter.
  
  The argument @var{horizontal-type} is meant to specify whether and
  where to have horizontal scroll bars, but since they are not
! implemented, it has no effect.
  @end defun
  
  @defun window-scroll-bars &optional window
--- 2797,2815 ----
  @code{set-window-scroll-bars} to specify what to do for a specific window:
  
  @defun set-window-scroll-bars window width &optional vertical-type 
horizontal-type
! This function sets the width and type of scroll bars for window
! @var{window}.
! 
  @var{width} specifies the scroll bar width in pixels (@code{nil} means
! use the width specified for the frame).  @var{vertical-type} specifies
! whether to have a vertical scroll bar and, if so, where.  The possible
! values are @code{left}, @code{right} and @code{nil}, just like the
! values of the @code{vertical-scroll-bars} frame parameter.
  
  The argument @var{horizontal-type} is meant to specify whether and
  where to have horizontal scroll bars, but since they are not
! implemented, it has no effect.  If @var{window} is @code{nil}, the
! selected window is used.
  @end defun
  
  @defun window-scroll-bars &optional window
***************
*** 2644,2649 ****
--- 2833,2858 ----
  window take note of the new values by calling @code{set-window-buffer}
  specifying the same buffer that is already displayed.
  
+ @node Pointer Shape
+ @section Pointer Shape
+ 
+   Normally, the mouse pointer has the @code{text} shape over text and
+ the @code{arrow} shape over window areas which do not correspond to
+ any buffer text.  You can specify the mouse pointer shape over text or
+ images via the @code{pointer} text property, and for images with the
+ @code{:pointer} and @code{:map} image properties.
+ 
+   The available pointer shapes are: @code{text} (or @code{nil}),
+ @code{arrow}, @code{hand}, @code{vdrag}, @code{hdrag},
+ @code{modeline}, and @code{hourglass}.
+ 
+ @defvar void-text-area-pointer
+ @tindex void-text-area-pointer
+ This variable specifies the mouse pointer shape in void text areas,
+ i.e. the areas after the end of a line or below the last line in the
+ buffer.  The default is to use the @code{arrow} (non-text) pointer.
+ @end defvar
+ 
  @node Display Property
  @section The @code{display} Property
  @cindex display specification
***************
*** 2659,2664 ****
--- 2868,2874 ----
  
  @menu
  * Specified Space::      Displaying one space with a specified width.
+ * Pixel Specification::  Specifying space width or height in pixels.
  * Other Display Specs::  Displaying an image; magnifying text; moving it
                            up or down on the page; adjusting the width
                            of spaces within text.
***************
*** 2683,2691 ****
  
  @table @code
  @item :width @var{width}
! Specifies that the space width should be @var{width} times the normal
! character width.  @var{width} can be an integer or floating point
! number.
  
  @item :relative-width @var{factor}
  Specifies that the width of the stretch should be computed from the
--- 2893,2902 ----
  
  @table @code
  @item :width @var{width}
! If @var{width} is an integer or floating point number, it specifies
! that the space width should be @var{width} times the normal character
! width.  @var{width} can also be a @dfn{pixel width} specification
! (@pxref{Pixel Specification}).
  
  @item :relative-width @var{factor}
  Specifies that the width of the stretch should be computed from the
***************
*** 2694,2734 ****
  character, multiplied by @var{factor}.
  
  @item :align-to @var{hpos}
! Specifies that the space should be wide enough to reach @var{hpos}.  The
! value @var{hpos} is measured in units of the normal character width.  It
! may be an integer or a floating point number.
  @end table
  
    You should use one and only one of the above properties.  You can
! also specify the height of the space, with other properties:
  
  @table @code
  @item :height @var{height}
! Specifies the height of the space, as @var{height},
! measured in terms of the normal line height.
  
  @item :relative-height @var{factor}
  Specifies the height of the space, multiplying the ordinary height
  of the text having this display specification by @var{factor}.
  
  @item :ascent @var{ascent}
! Specifies that @var{ascent} percent of the height of the space should be
! considered as the ascent of the space---that is, the part above the
! baseline.  The value of @var{ascent} must be a non-negative number no
! greater than 100.
  @end table
  
    Don't use both @code{:height} and @code{:relative-height} together.
  
  @node Other Display Specs
  @subsection Other Display Specifications
  
  @table @code
  @item (image . @var{image-props})
  This is in fact an image descriptor (@pxref{Images}).  When used as a
  display specification, it means to display the image instead of the text
  that has the display specification.
  
  @item ((margin nil) @var{string})
  @itemx @var{string}
  A display specification of this form means to display @var{string}
--- 2905,3035 ----
  character, multiplied by @var{factor}.
  
  @item :align-to @var{hpos}
! Specifies that the space should be wide enough to reach @var{hpos}.
! If @var{hpos} is a number, it is measured in units of the normal
! character width.  @var{hpos} can also be a @dfn{pixel width}
! specification (@pxref{Pixel Specification}).
  @end table
  
    You should use one and only one of the above properties.  You can
! also specify the height of the space, with these properties:
  
  @table @code
  @item :height @var{height}
! Specifies the height of the space.
! If @var{height} is an integer or floating point number, it specifies
! that the space height should be @var{height} times the normal character
! height.  The @var{height} may also be a @dfn{pixel height} specification
! (@pxref{Pixel Specification}).
  
  @item :relative-height @var{factor}
  Specifies the height of the space, multiplying the ordinary height
  of the text having this display specification by @var{factor}.
  
  @item :ascent @var{ascent}
! If the value of @var{ascent} is a non-negative number no greater than
! 100, it specifies that @var{ascent} percent of the height of the space
! should be considered as the ascent of the space---that is, the part
! above the baseline.  The ascent may also be specified in pixel units
! with a @dfn{pixel ascent} specification (@pxref{Pixel Specification}).
! 
  @end table
  
    Don't use both @code{:height} and @code{:relative-height} together.
  
+   The @code{:height} and @code{:align-to} properties are supported on
+ non-graphic terminals, but the other space properties in this section
+ are not.
+ 
+ @node Pixel Specification
+ @subsection Pixel Specification for Spaces
+ @cindex spaces, pixel specification
+ 
+   The value of the @code{:width}, @code{:align-to}, @code{:height},
+ and @code{:ascent} properties can be a special kind of expression that
+ is evaluated during redisplay.  The result of the evaluation is used
+ as an absolute number of pixels.
+ 
+   The following expressions are supported:
+ 
+ @example
+ @group
+   @var{expr} ::= @var{num} | (@var{num}) | @var{unit} | @var{elem} | 
@var{pos} | IMAGE | @var{form}
+   @var{num}  ::= @var{integer} | @var{float} | @var{symbol}
+   @var{unit} ::= in | mm | cm | width | height
+   @var{elem} ::= left-fringe | right-fringe | left-margin | right-margin
+         |  scroll-bar | text
+   @var{pos}  ::= left | center | right
+   @var{form} ::= (@var{num} . @var{expr}) | (@var{op} @var{expr} ...)
+   @var{op}   ::= + | -
+ @end group
+ @end example
+ 
+   The form @var{num} specifies a fraction of the default frame font
+ height or width.  The form @code{(@var{num})} specifies an absolute
+ number of pixels.  If @var{num} is a symbol, @var{symbol}, its
+ buffer-local variable binding is used.
+ 
+   The @code{in}, @code{mm}, and @code{cm} units specify the number of
+ pixels per inch, millimeter, and centimeter, respectively.  The
+ @code{width} and @code{height} units correspond to the default width
+ and height of the current face.  An image specification @code{IMAGE}
+ corresponds to the width or height of the image.
+ 
+   The @code{left-fringe}, @code{right-fringe}, @code{left-margin},
+ @code{right-margin}, @code{scroll-bar}, and @code{text} elements
+ specify to the width of the corresponding area of the window.
+ 
+   The @code{left}, @code{center}, and @code{right} positions can be
+ used with @code{:align-to} to specify a position relative to the left
+ edge, center, or right edge of the text area.
+ 
+   Any of the above window elements (except @code{text}) can also be
+ used with @code{:align-to} to specify that the position is relative to
+ the left edge of the given area.  Once the base offset for a relative
+ position has been set (by the first occurrence of one of these
+ symbols), further occurences of these symbols are interpreted as the
+ width of the specified area.  For example, to align to the center of
+ the left-margin, use
+ 
+ @example
+ :align-to (+ left-margin (0.5 . left-margin))
+ @end example
+ 
+   If no specific base offset is set for alignment, it is always relative
+ to the left edge of the text area.  For example, @samp{:align-to 0} in a
+ header-line aligns with the first text column in the text area.
+ 
+   A value of the form @code{(@var{num} . @var{expr})} stands
+ multiplying the values of @var{num} and @var{expr}.  For example,
+ @code{(2 . in)} specifies a width of 2 inches, while @code{(0.5 .
+ IMAGE)} specifies half the width (or height) of the specified image.
+ 
+   The form @code{(+ @var{expr} ...)} adds up the value of the
+ expressions.  The form @code{(- @var{expr} ...)} negates or subtracts
+ the value of the expressions.
+ 
  @node Other Display Specs
  @subsection Other Display Specifications
  
+   Here are the other sorts of display specifications that you can use
+ in the @code{display} text property.
+ 
  @table @code
  @item (image . @var{image-props})
  This is in fact an image descriptor (@pxref{Images}).  When used as a
  display specification, it means to display the image instead of the text
  that has the display specification.
  
+ @item (slice @var{x} @var{y} @var{width} @var{height})
+ This specification together with @code{image} specifies a @dfn{slice}
+ (a partial area) of the image to display.  The elements @var{y} and
+ @var{x} specify the top left corner of the slice, within the image;
+ @var{width} and @var{height} specify the width and height of the
+ slice.  Integer values are numbers of pixels.  A floating point number
+ in the range 0.0--1.0 stands for that fraction of the width or height
+ of the entire image.
+ 
  @item ((margin nil) @var{string})
  @itemx @var{string}
  A display specification of this form means to display @var{string}
***************
*** 3105,3110 ****
--- 3406,3448 ----
  If @var{mask} is @code{nil}, remove a mask from the image, if it has
  one.  Images in some formats include a mask which can be removed by
  specifying @code{:mask nil}.
+ 
+ @item :pointer @var{shape}
+ This specifies the pointer shape when the mouse pointer is over this
+ image.  @xref{Pointer Shapes}, for available pointer shapes.
+ 
+ @item :map @var{map}
+ This associates an image map of @dfn{hot spots} with this image.
+ 
+ An image map is an alist where each element has the format
+ @code{(@var{area} @var{id} @var{plist})}.  An @var{area} is specified
+ as either a rectangle, a circle, or a polygon.
+ 
+ A rectangle is a cons
+ @code{(rect . ((@var{x0} . @var{y0}) . (@var{x1} . @var{y1})))}
+ which specifies the pixel coordinates of the upper left and bottom right
+ corners of the rectangle area.
+ 
+ A circle is a cons
+ @code{(circle . ((@var{x0} . @var{y0}) . @var{r}))}
+ which specifies the center and the radius of the circle; @var{r} may
+ be a float or integer.
+ 
+ A polygon is a cons
+ @code{(poly . address@hidden @var{y0} @var{x1} @var{y1} ...])}
+ where each pair in the vector describes one corner in the polygon.
+ 
+ When the mouse pointer is above a hot-spot area of an image, the
+ @var{plist} of that hot-spot is consulted; if it contains a @code{help-echo}
+ property it defines a tool-tip for the hot-spot, and if it contains
+ a @code{pointer} property, it defines the shape of the mouse cursor when
+ it is over the hot-spot.
+ @xref{Pointer Shapes}, for available pointer shapes.
+ 
+ When you click the mouse when the mouse pointer is over a hot-spot, an
+ event is composed by combining the @var{id} of the hot-spot with the
+ mouse event; for instance, @code{[area4 mouse-1]} if the hot-spot's
+ @var{id} is @code{area4}.
  @end table
  
  @defun image-mask-p spec &optional frame
***************
*** 3372,3378 ****
  property yourself, but it is easier to use the functions in this
  section.
  
! @defun insert-image image &optional string area
  This function inserts @var{image} in the current buffer at point.  The
  value @var{image} should be an image descriptor; it could be a value
  returned by @code{create-image}, or the value of a symbol defined with
--- 3710,3716 ----
  property yourself, but it is easier to use the functions in this
  section.
  
! @defun insert-image image &optional string area slice
  This function inserts @var{image} in the current buffer at point.  The
  value @var{image} should be an image descriptor; it could be a value
  returned by @code{create-image}, or the value of a symbol defined with
***************
*** 3385,3395 ****
--- 3723,3748 ----
  @code{nil} or omitted, the image is displayed at point within the
  buffer's text.
  
+ The argument @var{slice} specifies a slice of the image to insert.  If
+ @var{slice} is @code{nil} or omitted the whole image is inserted.
+ Otherwise, @var{slice} is a list @code{(@var{x} @var{y} @var{width}
+ @var{height})} which specifies the @var{x} and @var{y} positions and
+ @var{width} and @var{height} of the image area to insert.  Integer
+ values are in units of pixels.  A floating point number in the range
+ 0.0--1.0 stands for that fraction of the width or height of the entire
+ image.
+ 
  Internally, this function inserts @var{string} in the buffer, and gives
  it a @code{display} property which specifies @var{image}.  @xref{Display
  Property}.
  @end defun
  
+ @defun insert-sliced-image image &optional string area rows cols
+ This function inserts @var{image} in the current buffer at point, like
+ @code{insert-image}, but splits the image into @address@hidden
+ equally sized slices.
+ @end defun
+ 
  @defun put-image image pos &optional string area
  This function puts image @var{image} in front of @var{pos} in the
  current buffer.  The argument @var{pos} should be an integer or a
***************
*** 3498,3504 ****
  * Making Buttons::         Adding buttons to Emacs buffers.
  * Manipulating Buttons::   Getting and setting properties of buttons.
  * Button Buffer Commands:: Buffer-wide commands and bindings for buttons.
! * Manipulating Button Types:: 
  @end menu
  
  @node Button Properties
--- 3851,3857 ----
  * Making Buttons::         Adding buttons to Emacs buffers.
  * Manipulating Buttons::   Getting and setting properties of buttons.
  * Button Buffer Commands:: Buffer-wide commands and bindings for buttons.
! * Manipulating Button Types::
  @end menu
  
  @node Button Properties