2 @c This is part of the XEmacs Lisp Reference Manual.
3 @c Copyright (C) 1995, 1996 Ben Wing.
4 @c See the file lispref.texi for copying conditions.
5 @setfilename ../../info/glyphs.info
6 @node Glyphs, Annotations, Faces and Window-System Objects, top
10 A @dfn{glyph} is an object that is used for pixmaps and images of all
11 sorts, as well as for things that ``act'' like pixmaps, such as
12 non-textual strings (@dfn{annotations}) displayed in a buffer or in the
13 margins. It is used in begin-glyphs and end-glyphs attached to extents,
14 marginal and textual annotations, overlay arrows (@code{overlay-arrow-*}
15 variables), toolbar buttons, mouse pointers, frame icons, truncation and
16 continuation markers, and the like. (Basically, any place there is an
17 image or something that acts like an image, there will be a glyph object
20 The actual image that is displayed (as opposed to its position or
21 clipping) is defined by an @dfn{image specifier} object contained
22 within the glyph. The separation between an image specifier object
23 and a glyph object is made because the glyph includes other properties
24 than just the actual image: e.g. the face it is displayed in (for text
25 images), the alignment of the image (when it is in a buffer), etc.
28 This function returns @code{t} if @var{object} is a glyph.
32 * Glyph Functions:: Functions for working with glyphs.
33 * Images:: Graphical images displayed in a frame.
34 * Glyph Types:: Each glyph has a particular type.
35 * Mouse Pointer:: Controlling the mouse pointer.
36 * Redisplay Glyphs:: Glyphs controlling various redisplay functions.
37 * Subwindows:: Inserting an externally-controlled subwindow
42 @section Glyph Functions
45 * Creating Glyphs:: Creating new glyphs.
46 * Glyph Properties:: Accessing and modifying a glyph's properties.
47 * Glyph Convenience Functions::
48 Convenience functions for accessing particular
49 properties of a glyph.
50 * Glyph Dimensions:: Determining the height, width, etc. of a glyph.
54 @subsection Creating Glyphs
56 @defun make-glyph &optional spec-list type
57 This function creates a new glyph object of type @var{type}.
59 @var{spec-list} is used to initialize the glyph's image. It is
60 typically an image instantiator (a string or a vector; @ref{Image
61 Specifiers}), but can also be a list of such instantiators (each one in
62 turn is tried until an image is successfully produced), a cons of a
63 locale (frame, buffer, etc.) and an instantiator, a list of such conses,
64 or any other form accepted by @code{canonicalize-spec-list}.
65 @xref{Specifiers}, for more information about specifiers.
67 @var{type} specifies the type of the glyph, which specifies in which
68 contexts the glyph can be used, and controls the allowable image types
69 into which the glyph's image can be instantiated. @var{type} should be
70 one of @code{buffer} (used for glyphs in an extent, the modeline, the
71 toolbar, or elsewhere in a buffer), @code{pointer} (used for the
72 mouse-pointer), or @code{icon} (used for a frame's icon), and defaults
73 to @code{buffer}. @xref{Glyph Types}.
76 @defun make-glyph-internal &optional type
77 This function creates a new, uninitialized glyph of type @var{type}.
80 @defun make-pointer-glyph &optional spec-list
81 This function is equivalent to calling @code{make-glyph} with a
82 @var{type} of @code{pointer}.
85 @defun make-icon-glyph &optional spec-list
86 This function is equivalent to calling @code{make-glyph} with a
87 @var{type} of @code{icon}.
90 @node Glyph Properties
91 @subsection Glyph Properties
93 Each glyph has a list of properties, which control all of the aspects of
94 the glyph's appearance. The following symbols have predefined meanings:
98 The image used to display the glyph.
101 Percent above baseline that glyph is to be displayed. Only for glyphs
102 displayed inside of a buffer.
105 Whether the glyph contributes to the height of the line it's on.
106 Only for glyphs displayed inside of a buffer.
109 Face of this glyph (@emph{not} a specifier).
112 @defun set-glyph-property glyph property value &optional locale tag-set how-to-add
113 This function changes a property of a @var{glyph}.
115 For built-in properties, the actual value of the property is a specifier
116 and you cannot change this; but you can change the specifications within
117 the specifier, and that is what this function will do. For user-defined
118 properties, you can use this function to either change the actual value
119 of the property or, if this value is a specifier, change the
120 specifications within it.
122 If @var{property} is a built-in property, the specifications to be added
123 to this property can be supplied in many different ways:
127 If @var{value} is a simple instantiator (e.g. a string naming a pixmap
128 filename) or a list of instantiators, then the instantiator(s) will be
129 added as a specification of the property for the given @var{locale}
130 (which defaults to @code{global} if omitted).
133 If @var{value} is a list of specifications (each of which is a cons of a
134 locale and a list of instantiators), then @var{locale} must be
135 @code{nil} (it does not make sense to explicitly specify a locale in
136 this case), and specifications will be added as given.
139 If @var{value} is a specifier (as would be returned by
140 @code{glyph-property} if no @var{locale} argument is given), then some
141 or all of the specifications in the specifier will be added to the
142 property. In this case, the function is really equivalent to
143 @code{copy-specifier} and @var{locale} has the same semantics (if it is
144 a particular locale, the specification for the locale will be copied; if
145 a locale type, specifications for all locales of that type will be
146 copied; if @code{nil} or @code{all}, then all specifications will be
150 @var{how-to-add} should be either @code{nil} or one of the symbols
151 @code{prepend}, @code{append}, @code{remove-tag-set-prepend},
152 @code{remove-tag-set-append}, @code{remove-locale},
153 @code{remove-locale-type}, or @code{remove-all}. See
154 @code{copy-specifier} and @code{add-spec-to-specifier} for a description
155 of what each of these means. Most of the time, you do not need to worry
156 about this argument; the default behavior usually is fine.
158 In general, it is OK to pass an instance object (e.g. as returned by
159 @code{glyph-property-instance}) as an instantiator in place of an actual
160 instantiator. In such a case, the instantiator used to create that
161 instance object will be used (for example, if you set a font-instance
162 object as the value of the @code{font} property, then the font name used
163 to create that object will be used instead). If some cases, however,
164 doing this conversion does not make sense, and this will be noted in the
165 documentation for particular types of instance objects.
167 If @var{property} is not a built-in property, then this function will
168 simply set its value if @var{locale} is @code{nil}. However, if
169 @var{locale} is given, then this function will attempt to add
170 @var{value} as the instantiator for the given @var{locale}, using
171 @code{add-spec-to-specifier}. If the value of the property is not a
172 specifier, it will automatically be converted into a @code{generic}
176 @defun glyph-property glyph property &optional locale
177 This function returns @var{glyph}'s value of the given @var{property}.
179 If @var{locale} is omitted, the @var{glyph}'s actual value for
180 @var{property} will be returned. For built-in properties, this will be
181 a specifier object of a type appropriate to the property (e.g. a font or
182 color specifier). For other properties, this could be anything.
184 If @var{locale} is supplied, then instead of returning the actual value,
185 the specification(s) for the given locale or locale type will be
186 returned. This will only work if the actual value of @var{property} is
187 a specifier (this will always be the case for built-in properties, but
188 may or may not apply to user-defined properties). If the actual value
189 of @var{property} is not a specifier, this value will simply be returned
190 regardless of @var{locale}.
192 The return value will be a list of instantiators (e.g. vectors
193 specifying pixmap data), or a list of specifications, each of which is a
194 cons of a locale and a list of instantiators. Specifically, if
195 @var{locale} is a particular locale (a buffer, window, frame, device, or
196 @code{global}), a list of instantiators for that locale will be
197 returned. Otherwise, if @var{locale} is a locale type (one of the
198 symbols @code{buffer}, @code{window}, @code{frame}, or @code{device}),
199 the specifications for all locales of that type will be returned.
200 Finally, if @var{locale} is @code{all}, the specifications for all
201 locales of all types will be returned.
203 The specifications in a specifier determine what the value of
204 @var{property} will be in a particular @dfn{domain} or set of
205 circumstances, which is typically a particular Emacs window along with
206 the buffer it contains and the frame and device it lies within. The
207 value is derived from the instantiator associated with the most specific
208 locale (in the order buffer, window, frame, device, and @code{global})
209 that matches the domain in question. In other words, given a domain
210 (i.e. an Emacs window, usually), the specifier for @var{property} will
211 first be searched for a specification whose locale is the buffer
212 contained within that window; then for a specification whose locale is
213 the window itself; then for a specification whose locale is the frame
214 that the window is contained within; etc. The first instantiator that
215 is valid for the domain (usually this means that the instantiator is
216 recognized by the device [i.e. the X server or TTY device] that the
217 domain is on). The function @code{glyph-property-instance} actually does
218 all this, and is used to determine how to display the glyph.
221 @defun glyph-property-instance glyph property &optional domain default no-fallback
222 This function returns the instance of @var{glyph}'s @var{property} in the
223 specified @var{domain}.
225 Under most circumstances, @var{domain} will be a particular window, and
226 the returned instance describes how the specified property actually is
227 displayed for that window and the particular buffer in it. Note that
228 this may not be the same as how the property appears when the buffer is
229 displayed in a different window or frame, or how the property appears in
230 the same window if you switch to another buffer in that window; and in
231 those cases, the returned instance would be different.
233 The returned instance is an image-instance object, and you can query it
234 using the appropriate image instance functions. For example, you could use
235 @code{image-instance-depth} to find out the depth (number of color
236 planes) of a pixmap displayed in a particular window. The results might
237 be different from the results you would get for another window (perhaps
238 the user specified a different image for the frame that window is on; or
239 perhaps the same image was specified but the window is on a different X
240 server, and that X server has different color capabilities from this
243 @var{domain} defaults to the selected window if omitted.
245 @var{domain} can be a frame or device, instead of a window. The value
246 returned for such a domain is used in special circumstances when a
247 more specific domain does not apply; for example, a frame value might be
248 used for coloring a toolbar, which is conceptually attached to a frame
249 rather than a particular window. The value is also useful in
250 determining what the value would be for a particular window within the
251 frame or device, if it is not overridden by a more specific
254 If @var{property} does not name a built-in property, its value will
255 simply be returned unless it is a specifier object, in which case it
256 will be instanced using @code{specifier-instance}.
258 Optional arguments @var{default} and @var{no-fallback} are the same as
259 in @code{specifier-instance}. @xref{Specifiers}.
262 @defun remove-glyph-property glyph property &optional locale tag-set exact-p
263 This function removes a property from a glyph. For built-in properties,
264 this is analogous to @code{remove-specifier}. @xref{Specifiers,
265 remove-specifier-p}, for the meaning of the @var{locale}, @var{tag-set},
266 and @var{exact-p} arguments.
269 @node Glyph Convenience Functions
270 @subsection Glyph Convenience Functions
272 The following functions are provided for working with specific
273 properties of a glyph. Note that these are exactly like calling
274 the general functions described above and passing in the
275 appropriate value for @var{property}.
277 Remember that if you want to determine the ``value'' of a
278 specific glyph property, you probably want to use the @code{*-instance}
279 functions. For example, to determine whether a glyph contributes
280 to its line height, use @code{glyph-contrib-p-instance}, not
281 @code{glyph-contrib-p}. (The latter will return a boolean specifier
282 or a list of specifications, and you probably aren't concerned with
285 @defun glyph-image glyph &optional locale
286 This function is equivalent to calling @code{glyph-property} with
287 a property of @code{image}. The return value will be an image
288 specifier if @var{locale} is @code{nil} or omitted; otherwise,
289 it will be a specification or list of specifications.
292 @defun set-glyph-image glyph spec &optional locale tag-set how-to-add
293 This function is equivalent to calling @code{set-glyph-property} with
294 a property of @code{image}.
297 @defun glyph-image-instance glyph &optional domain default no-fallback
298 This function returns the instance of @var{glyph}'s image in the given
299 @var{domain}, and is equivalent to calling
300 @code{glyph-property-instance} with a property of @code{image}. The
301 return value will be an image instance.
303 Normally @var{domain} will be a window or @code{nil} (meaning the
304 selected window), and an instance object describing how the image
305 appears in that particular window and buffer will be returned.
308 @defun glyph-contrib-p glyph &optional locale
309 This function is equivalent to calling @code{glyph-property} with
310 a property of @code{contrib-p}. The return value will be a boolean
311 specifier if @var{locale} is @code{nil} or omitted; otherwise,
312 it will be a specification or list of specifications.
315 @defun set-glyph-contrib-p glyph spec &optional locale tag-set how-to-add
316 This function is equivalent to calling @code{set-glyph-property} with
317 a property of @code{contrib-p}.
320 @defun glyph-contrib-p-instance glyph &optional domain default no-fallback
321 This function returns whether the glyph contributes to its line height
322 in the given @var{domain}, and is equivalent to calling
323 @code{glyph-property-instance} with a property of @code{contrib-p}. The
324 return value will be either @code{nil} or @code{t}. (Normally @var{domain}
325 will be a window or @code{nil}, meaning the selected window.)
328 @defun glyph-baseline glyph &optional locale
329 This function is equivalent to calling @code{glyph-property} with a
330 property of @code{baseline}. The return value will be a specifier if
331 @var{locale} is @code{nil} or omitted; otherwise, it will be a
332 specification or list of specifications.
335 @defun set-glyph-baseline glyph spec &optional locale tag-set how-to-add
336 This function is equivalent to calling @code{set-glyph-property} with
337 a property of @code{baseline}.
340 @defun glyph-baseline-instance glyph &optional domain default no-fallback
341 This function returns the instance of @var{glyph}'s baseline value in
342 the given @var{domain}, and is equivalent to calling
343 @code{glyph-property-instance} with a property of @code{baseline}. The
344 return value will be an integer or @code{nil}.
346 Normally @var{domain} will be a window or @code{nil} (meaning the
347 selected window), and an instance object describing the baseline value
348 appears in that particular window and buffer will be returned.
351 @defun glyph-face glyph
352 This function returns the face of @var{glyph}. (Remember, this is
353 not a specifier, but a simple property.)
356 @defun set-glyph-face glyph face
357 This function changes the face of @var{glyph} to @var{face}.
360 @node Glyph Dimensions
361 @subsection Glyph Dimensions
363 @defun glyph-width glyph &optional window
364 This function returns the width of @var{glyph} on @var{window}. This
365 may not be exact as it does not take into account all of the context
369 @defun glyph-ascent glyph &optional window
370 This function returns the ascent value of @var{glyph} on @var{window}.
371 This may not be exact as it does not take into account all of the
372 context that redisplay will.
375 @defun glyph-descent glyph &optional window
376 This function returns the descent value of @var{glyph} on @var{window}.
377 This may not be exact as it does not take into account all of the
378 context that redisplay will.
381 @defun glyph-height glyph &optional window
382 This function returns the height of @var{glyph} on @var{window}. (This
383 is equivalent to the sum of the ascent and descent values.) This may
384 not be exact as it does not take into account all of the context that
392 * Image Specifiers:: Specifying how an image will appear.
393 * Image Instantiator Conversion::
394 Conversion is applied to image instantiators
395 at the time they are added to an
396 image specifier or at the time they
397 are passed to @code{make-image-instance}.
398 * Image Instances:: What an image specifier gets instanced as.
401 @node Image Specifiers
402 @subsection Image Specifiers
403 @cindex image specifiers
405 An image specifier is used to describe the actual image of a glyph.
406 It works like other specifiers (@pxref{Specifiers}), in that it contains
407 a number of specifications describing how the image should appear in a
408 variety of circumstances. These specifications are called @dfn{image
409 instantiators}. When XEmacs wants to display the image, it instantiates
410 the image into an @dfn{image instance}. Image instances are their own
411 primitive object type (similar to font instances and color instances),
412 describing how the image appears in a particular domain. (On the other
413 hand, image instantiators, which are just descriptions of how the image
414 should appear, are represented using strings or vectors.)
416 @defun image-specifier-p object
417 This function returns non-@code{nil} if @var{object} is an image specifier.
418 Usually, an image specifier results from calling @code{glyph-image} on
422 @defun make-image-specifier spec-list
423 This function creates a new image specifier object and initializes
424 it according to @var{spec-list}. It is unlikely that you will ever
425 want to do this, but this function is provided for completeness and
426 for experimentation purposes. @xref{Specifiers}.
429 Image instantiators come in many formats: @code{xbm}, @code{xpm},
430 @code{gif}, @code{jpeg}, etc. This describes the format of the data
431 describing the image. The resulting image instances also come in many
432 types---@code{mono-pixmap}, @code{color-pixmap}, @code{text},
433 @code{pointer}, etc. This refers to the behavior of the image and the
434 sorts of places it can appear. (For example, a color-pixmap image has
435 fixed colors specified for it, while a mono-pixmap image comes in two
436 unspecified shades ``foreground'' and ``background'' that are determined
437 from the face of the glyph or surrounding text; a text image appears as
438 a string of text and has an unspecified foreground, background, and
439 font; a pointer image behaves like a mono-pixmap image but can only be
440 used as a mouse pointer [mono-pixmap images cannot be used as mouse
441 pointers]; etc.) It is important to keep the distinction between image
442 instantiator format and image instance type in mind. Typically, a given
443 image instantiator format can result in many different image instance
444 types (for example, @code{xpm} can be instanced as @code{color-pixmap},
445 @code{mono-pixmap}, or @code{pointer}; whereas @code{cursor-font} can be
446 instanced only as @code{pointer}), and a particular image instance type
447 can be generated by many different image instantiator formats (e.g.
448 @code{color-pixmap} can be generated by @code{xpm}, @code{gif},
451 @xref{Image Instances}, for a more detailed discussion of image
454 An image instantiator should be a string or a vector of the form
457 @code{[@var{format} @var{:keyword} @var{value} ...]}
460 i.e. a format symbol followed by zero or more alternating keyword-value
461 pairs. The @dfn{format} field should be a symbol, one of
465 Don't display anything; no keywords are valid for this. Can only be
466 instanced as @code{nothing}.
468 Display this image as a text string. Can only be instanced
469 as @code{text}, although support for instancing as @code{mono-pixmap}
471 @item formatted-string
472 Display this image as a text string with replaceable fields,
473 similar to a modeline format string; not currently implemented.
475 An X bitmap; only if X support was compiled into this XEmacs. Can be
476 instanced as @code{mono-pixmap}, @code{color-pixmap}, or
479 An XPM pixmap; only if XPM support was compiled into this XEmacs. Can
480 be instanced as @code{color-pixmap}, @code{mono-pixmap}, or
481 @code{pointer}. XPM is an add-on library for X that was designed to
482 rectify the shortcomings of the XBM format. Most implementations of X
483 include the XPM library as a standard part. If your vendor does not, it
484 is highly recommended that you download it and install it. You can get
485 it from the standard XEmacs FTP site, among other places.
487 An X-Face bitmap, used to encode people's faces in e-mail messages;
488 only if X-Face support was compiled into this XEmacs. Can be instanced
489 as @code{mono-pixmap}, @code{color-pixmap}, or @code{pointer}.
491 A GIF87 or GIF89 image; only if GIF support was compiled into this
492 XEmacs. Can be instanced as @code{color-pixmap}. Note that XEmacs
493 includes GIF decoding functions as a standard part of it, so if you have
494 X support, you will normally have GIF support, unless you explicitly
495 disable it at configure time.
497 A JPEG-format image; only if JPEG support was compiled into this
498 XEmacs. Can be instanced as @code{color-pixmap}. If you have the JPEG
499 libraries present on your system when XEmacs is built, XEmacs will
500 automatically detect this and use them, unless you explicitly disable it
503 A PNG/GIF24 image; only if PNG support was compiled into this XEmacs.
504 Can be instanced as @code{color-pixmap}.
506 A TIFF-format image; only if TIFF support was compiled into this XEmacs.
508 One of the standard cursor-font names, such as @samp{watch} or
509 @samp{right_ptr} under X. Under X, this is, more specifically, any of
510 the standard cursor names from appendix B of the Xlib manual [also known
511 as the file @file{<X11/cursorfont.h>}] minus the @samp{XC_} prefix. On
512 other window systems, the valid names will be specific to the type of
513 window system. Can only be instanced as @code{pointer}.
515 A glyph from a font; i.e. the name of a font, and glyph index into it
516 of the form @samp{@var{font} fontname index [[mask-font] mask-index]}.
517 Only if X support was compiled into this XEmacs. Currently can only be
518 instanced as @code{pointer}, although this should probably be fixed.
520 An embedded X window; not currently implemented.
522 XEmacs tries to guess what format the data is in. If X support exists,
523 the data string will be checked to see if it names a filename. If so,
524 and this filename contains XBM or XPM data, the appropriate sort of
525 pixmap or pointer will be created. [This includes picking up any
526 specified hotspot or associated mask file.] Otherwise, if @code{pointer}
527 is one of the allowable image-instance types and the string names a
528 valid cursor-font name, the image will be created as a pointer.
529 Otherwise, the image will be displayed as text. If no X support exists,
530 the image will always be displayed as text.
533 The valid keywords are:
537 Inline data. For most formats above, this should be a string. For
538 XBM images, this should be a list of three elements: width, height, and
539 a string of bit data. This keyword is not valid for instantiator
540 format @code{nothing}.
543 Data is contained in a file. The value is the name of this file. If
544 both @code{:data} and @code{:file} are specified, the image is created
545 from what is specified in @code{:data} and the string in @code{:file}
546 becomes the value of the @code{image-instance-file-name} function when
547 applied to the resulting image-instance. This keyword is not valid for
548 instantiator formats @code{nothing}, @code{string},
549 @code{formatted-string}, @code{cursor-font}, @code{font}, and
554 For @code{xbm}, @code{xface}, @code{cursor-font}, and @code{font}.
555 These keywords allow you to explicitly specify foreground and background
556 colors. The argument should be anything acceptable to
557 @code{make-color-instance}. This will cause what would be a
558 @code{mono-pixmap} to instead be colorized as a two-color color-pixmap,
559 and specifies the foreground and/or background colors for a pointer
560 instead of black and white.
563 For @code{xbm} and @code{xface}. This specifies a mask to be used with the
564 bitmap. The format is a list of width, height, and bits, like for
568 For @code{xbm} and @code{xface}. This specifies a file containing the
569 mask data. If neither a mask file nor inline mask data is given for an
570 XBM image, and the XBM image comes from a file, XEmacs will look for a
571 mask file with the same name as the image file but with @samp{Mask} or
572 @samp{msk} appended. For example, if you specify the XBM file
573 @file{left_ptr} [usually located in @file{/usr/include/X11/bitmaps}],
574 the associated mask file @file{left_ptrmsk} will automatically be picked
579 For @code{xbm} and @code{xface}. These keywords specify a hotspot if
580 the image is instantiated as a @code{pointer}. Note that if the XBM
581 image file specifies a hotspot, it will automatically be picked up if no
582 explicit hotspot is given.
585 Only for @code{xpm}. This specifies an alist that maps strings that
586 specify symbolic color names to the actual color to be used for that
587 symbolic color (in the form of a string or a color-specifier object).
588 If this is not specified, the contents of @code{xpm-color-symbols} are
589 used to generate the alist.
592 If instead of a vector, the instantiator is a string, it will be
593 converted into a vector by looking it up according to the specs in the
594 @code{console-type-image-conversion-list} for the console type of
595 the domain (usually a window; sometimes a frame or device) over which
596 the image is being instantiated.
598 If the instantiator specifies data from a file, the data will be read in
599 at the time that the instantiator is added to the image specifier (which
600 may be well before the image is actually displayed), and the
601 instantiator will be converted into one of the inline-data forms, with
602 the filename retained using a @code{:file} keyword. This implies that
603 the file must exist when the instantiator is added to the image, but
604 does not need to exist at any other time (e.g. it may safely be a
607 @defun valid-image-instantiator-format-p format
608 This function returns non-@code{nil} if @var{format} is a valid image
609 instantiator format. Note that the return value for many formats listed
610 above depends on whether XEmacs was compiled with support for that format.
613 @defun image-instantiator-format-list
614 This function return a list of valid image-instantiator formats.
617 @defvar xpm-color-symbols
618 This variable holds definitions of logical color-names used when reading
619 XPM files. Elements of this list should be of the form
620 @code{(@var{color-name} @var{form-to-evaluate})}. The @var{color-name}
621 should be a string, which is the name of the color to define; the
622 @var{form-to-evaluate} should evaluate to a color specifier object, or a
623 string to be passed to @code{make-color-instance} (@pxref{Colors}). If
624 a loaded XPM file references a symbolic color called @var{color-name},
625 it will display as the computed color instead.
627 The default value of this variable defines the logical color names
628 @samp{"foreground"} and @samp{"background"} to be the colors of the
632 @defvar x-bitmap-file-path
633 A list of the directories in which X bitmap files may be found. If nil,
634 this is initialized from the @samp{"*bitmapFilePath"} resource. This is
635 used by the @code{make-image-instance} function (however, note that if
636 the environment variable @samp{XBMLANGPATH} is set, it is consulted
640 @node Image Instantiator Conversion
641 @subsection Image Instantiator Conversion
642 @cindex image instantiator conversion
643 @cindex conversion of image instantiators
645 @defun set-console-type-image-conversion-list console-type list
646 This function sets the image-conversion-list for consoles of the given
647 @var{console-type}. The image-conversion-list specifies how image
648 instantiators that are strings should be interpreted. Each element of
649 the list should be a list of two elements (a regular expression string
650 and a vector) or a list of three elements (the preceding two plus an
651 integer index into the vector). The string is converted to the vector
652 associated with the first matching regular expression. If a vector
653 index is specified, the string itself is substituted into that position
656 Note: The conversion above is applied when the image instantiator is
657 added to an image specifier, not when the specifier is actually
658 instantiated. Therefore, changing the image-conversion-list only affects
659 newly-added instantiators. Existing instantiators in glyphs and image
660 specifiers will not be affected.
663 @defun console-type-image-conversion-list console-type
664 This function returns the image-conversion-list for consoles of the given
668 @node Image Instances
669 @subsection Image Instances
670 @cindex image instances
672 Image-instance objects encapsulate the way a particular image (pixmap,
673 etc.) is displayed on a particular device.
675 In most circumstances, you do not need to directly create image
676 instances; use a glyph instead. However, it may occasionally be useful
677 to explicitly create image instances, if you want more control over the
678 instantiation process.
680 @defun image-instance-p object
681 This function returns non-@code{nil} if @var{object} is an image instance.
685 * Image Instance Types:: Each image instances has a particular type.
686 * Image Instance Functions:: Functions for working with image instances.
689 @node Image Instance Types
690 @subsubsection Image Instance Types
691 @cindex image instance types
693 Image instances come in a number of different types. The type
694 of an image instance specifies the nature of the image: Whether
695 it is a text string, a mono pixmap, a color pixmap, etc.
697 The valid image instance types are
701 Nothing is displayed.
704 Displayed as text. The foreground and background colors and the
705 font of the text are specified independent of the pixmap. Typically
706 these attributes will come from the face of the surrounding text,
707 unless a face is specified for the glyph in which the image appears.
710 Displayed as a mono pixmap (a pixmap with only two colors where the
711 foreground and background can be specified independent of the pixmap;
712 typically the pixmap assumes the foreground and background colors of
713 the text around it, unless a face is specified for the glyph in which
717 Displayed as a color pixmap.
720 Used as the mouse pointer for a window.
723 A child window that is treated as an image. This allows (e.g.)
724 another program to be responsible for drawing into the window.
725 Not currently implemented.
728 @defun valid-image-instance-type-p type
729 This function returns non-@code{nil} if @var{type} is a valid image
733 @defun image-instance-type-list
734 This function returns a list of the valid image instance types.
737 @defun image-instance-type image-instance
738 This function returns the type of the given image instance. The return
739 value will be one of @code{nothing}, @code{text}, @code{mono-pixmap},
740 @code{color-pixmap}, @code{pointer}, or @code{subwindow}.
743 @defun text-image-instance-p object
744 This function returns non-@code{nil} if @var{object} is an image
745 instance of type @code{text}.
748 @defun mono-pixmap-image-instance-p object
749 This function returns non-@code{nil} if @var{object} is an image
750 instance of type @code{mono-pixmap}.
753 @defun color-pixmap-image-instance-p object
754 This function returns non-@code{nil} if @var{object} is an image
755 instance of type @code{color-pixmap}.
758 @defun pointer-image-instance-p object
759 This function returns non-@code{nil} if @var{object} is an image
760 instance of type @code{pointer}.
763 @defun subwindow-image-instance-p object
764 This function returns non-@code{nil} if @var{object} is an image
765 instance of type @code{subwindow}.
768 @defun nothing-image-instance-p object
769 This function returns non-@code{nil} if @var{object} is an image
770 instance of type @code{nothing}.
773 @node Image Instance Functions
774 @subsubsection Image Instance Functions
776 @defun make-image-instance data &optional device dest-types no-error
777 This function creates a new image-instance object.
779 @var{data} is an image instantiator, which describes the image
780 (@pxref{Image Specifiers}).
782 @var{dest-types} should be a list of allowed image instance types that
783 can be generated. The @var{dest-types} list is unordered. If multiple
784 destination types are possible for a given instantiator, the ``most
785 natural'' type for the instantiator's format is chosen. (For XBM, the
786 most natural types are @code{mono-pixmap}, followed by
787 @code{color-pixmap}, followed by @code{pointer}. For the other normal
788 image formats, the most natural types are @code{color-pixmap}, followed
789 by @code{mono-pixmap}, followed by @code{pointer}. For the string and
790 formatted-string formats, the most natural types are @code{text},
791 followed by @code{mono-pixmap} (not currently implemented), followed by
792 @code{color-pixmap} (not currently implemented). The other formats can
793 only be instantiated as one type. (If you want to control more
794 specifically the order of the types into which an image is instantiated,
795 just call @code{make-image-instance} repeatedly until it succeeds,
796 passing less and less preferred destination types each time.
798 If @var{dest-types} is omitted, all possible types are allowed.
800 @var{no-error} controls what happens when the image cannot be generated.
801 If @var{nil}, an error message is generated. If @var{t}, no messages
802 are generated and this function returns @var{nil}. If anything else, a
803 warning message is generated and this function returns @var{nil}.
806 @defun colorize-image-instance image-instance foreground background
807 This function makes the image instance be displayed in the given
808 colors. Image instances come in two varieties: bitmaps, which are 1
809 bit deep which are rendered in the prevailing foreground and background
810 colors; and pixmaps, which are of arbitrary depth (including 1) and
811 which have the colors explicitly specified. This function converts a
812 bitmap to a pixmap. If the image instance was a pixmap already,
813 nothing is done (and @code{nil} is returned). Otherwise @code{t} is
817 @defun image-instance-name image-instance
818 This function returns the name of the given image instance.
821 @defun image-instance-string image-instance
822 This function returns the string of the given image instance. This will
823 only be non-@code{nil} for text image instances.
826 @defun image-instance-file-name image-instance
827 This function returns the file name from which @var{image-instance} was
831 @defun image-instance-mask-file-name image-instance
832 This function returns the file name from which @var{image-instance}'s
833 mask was read, if known.
836 @defun image-instance-depth image-instance
837 This function returns the depth of the image instance. This is 0 for a
838 mono pixmap, or a positive integer for a color pixmap.
841 @defun image-instance-height image-instance
842 This function returns the height of the image instance, in pixels.
845 @defun image-instance-width image-instance
846 This function returns the width of the image instance, in pixels.
849 @defun image-instance-hotspot-x image-instance
850 This function returns the X coordinate of the image instance's hotspot,
851 if known. This is a point relative to the origin of the pixmap. When
852 an image is used as a mouse pointer, the hotspot is the point on the
853 image that sits over the location that the pointer points to. This is,
854 for example, the tip of the arrow or the center of the crosshairs.
856 This will always be @code{nil} for a non-pointer image instance.
859 @defun image-instance-hotspot-y image-instance
860 This function returns the Y coordinate of the image instance's hotspot,
864 @defun image-instance-foreground image-instance
865 This function returns the foreground color of @var{image-instance}, if
866 applicable. This will be a color instance or @code{nil}. (It will only
867 be non-@code{nil} for colorized mono pixmaps and for pointers.)
870 @defun image-instance-background image-instance
871 This function returns the background color of @var{image-instance}, if
872 applicable. This will be a color instance or @code{nil}. (It will only
873 be non-@code{nil} for colorized mono pixmaps and for pointers.)
880 Each glyph has a particular type, which controls how the glyph's image
881 is generated. Each glyph type has a corresponding list of allowable
882 image instance types that can be generated. When you call
883 @code{glyph-image-instance} to retrieve the image instance of a glyph,
884 XEmacs does the equivalent of calling @code{make-image-instance} and
885 passing in @var{dest-types} the list of allowable image instance types
886 for the glyph's type.
890 @code{buffer} glyphs can be used as the begin-glyph or end-glyph of an
891 extent, in the modeline, and in the toolbar. Their image can be
892 instantiated as @code{nothing}, @code{mono-pixmap}, @code{color-pixmap},
893 @code{text}, and @code{subwindow}.
896 @code{pointer} glyphs can be used to specify the mouse pointer. Their
897 image can be instantiated as @code{pointer}.
900 @code{icon} glyphs can be used to specify the icon used when a frame is
901 iconified. Their image can be instantiated as @code{mono-pixmap} and
905 @defun glyph-type glyph
906 This function returns the type of the given glyph. The return value
907 will be a symbol, one of @code{buffer}, @code{pointer}, or @code{icon}.
910 @defun valid-glyph-type-p glyph-type
911 Given a @var{glyph-type}, this function returns non-@code{nil} if it is
915 @defun glyph-type-list
916 This function returns a list of valid glyph types.
919 @defun buffer-glyph-p object
920 This function returns non-@code{nil} if @var{object} is a glyph of type
924 @defun icon-glyph-p object
925 This function returns non-@code{nil} if @var{object} is a glyph of type
929 @defun pointer-glyph-p object
930 This function returns non-@code{nil} if @var{object} is a glyph of type
935 @section Mouse Pointer
937 @cindex cursor (mouse)
938 @cindex pointer (mouse)
939 @cindex mouse pointer
941 The shape of the mouse pointer when over a particular section of a frame
942 is controlled using various glyph variables. Since the image of a glyph
943 is a specifier, it can be controlled on a per-buffer, per-frame, per-window,
946 You should use @code{set-glyph-image} to set the following variables,
947 @emph{not} @code{setq}.
949 @defvr Glyph text-pointer-glyph
950 This variable specifies the shape of the mouse pointer when over text.
953 @defvr Glyph nontext-pointer-glyph
954 This variable specifies the shape of the mouse pointer when over a
955 buffer, but not over text. If unspecified in a particular domain,
956 @code{text-pointer-glyph} is used.
959 @defvr Glyph modeline-pointer-glyph
960 This variable specifies the shape of the mouse pointer when over the modeline.
961 If unspecified in a particular domain, @code{nontext-pointer-glyph} is used.
964 @defvr Glyph selection-pointer-glyph
965 This variable specifies the shape of the mouse pointer when over a
966 selectable text region. If unspecified in a particular domain,
967 @code{text-pointer-glyph} is used.
970 @defvr Glyph gc-pointer-glyph
971 This variable specifies the shape of the mouse pointer when a garbage
972 collection is in progress. If the selected window is on a window system
973 and this glyph specifies a value (i.e. a pointer image instance) in the
974 domain of the selected window, the pointer will be changed as specified
975 during garbage collection. Otherwise, a message will be printed in the
976 echo area, as controlled by @code{gc-message}.
979 @defvr Glyph busy-pointer-glyph
980 This variable specifies the shape of the mouse pointer when XEmacs is busy.
981 If unspecified in a particular domain, the pointer is not changed
985 @defvr Glyph menubar-pointer-glyph
986 This variable specifies the shape of the mouse pointer when over the
987 menubar. If unspecified in a particular domain, the
988 window-system-provided default pointer is used.
991 @defvr Glyph scrollbar-pointer-glyph
992 This variable specifies the shape of the mouse pointer when over a
993 scrollbar. If unspecified in a particular domain, the
994 window-system-provided default pointer is used.
997 @defvr Glyph toolbar-pointer-glyph
998 This variable specifies the shape of the mouse pointer when over a
999 toolbar. If unspecified in a particular domain,
1000 @code{nontext-pointer-glyph} is used.
1003 Internally, these variables are implemented in
1004 @code{default-mouse-motion-handler}, and thus only take effect when the
1005 mouse moves. That function calls @code{set-frame-pointer}, which sets
1006 the current mouse pointer for a frame.
1008 @defun set-frame-pointer frame image-instance
1009 This function sets the mouse pointer of @var{frame} to the given pointer
1010 image instance. You should not call this function directly.
1011 (If you do, the pointer will change again the next time the mouse moves.)
1014 @node Redisplay Glyphs
1015 @section Redisplay Glyphs
1017 @defvr Glyph truncation-glyph
1018 This variable specifies what is displayed at the end of truncated lines.
1021 @defvr Glyph continuation-glyph
1022 This variable specifies what is displayed at the end of wrapped lines.
1025 @defvr Glyph octal-escape-glyph
1026 This variable specifies what to prefix character codes displayed in octal
1030 @defvr Glyph hscroll-glyph
1031 This variable specifies what to display at the beginning of horizontally
1035 @defvr Glyph invisible-text-glyph
1036 This variable specifies what to use to indicate the presence of
1037 invisible text. This is the glyph that is displayed when an ellipsis is
1038 called for, according to @code{selective-display-ellipses} or
1039 @code{buffer-invisibility-spec}). Normally this is three dots (``...'').
1042 @defvr Glyph control-arrow-glyph
1043 This variable specifies what to use as an arrow for control characters.
1049 Subwindows are not currently implemented.
1051 @defun subwindowp object
1052 This function returns non-@code{nil} if @var{object} is a subwindow.