view src/glyphs-widget.c @ 2367:ecf1ebac70d8

[xemacs-hg @ 2004-11-04 23:05:23 by ben] commit mega-patch configure.in: Turn off -Winline and -Wchar-subscripts. Use the right set of cflags when compiling modules. Rewrite ldap configuration to separate the inclusion of lber (needed in recent Cygwin) from the basic checks for the needed libraries. add a function for MAKE_JUNK_C; initially code was added to generate xemacs.def using this, but it will need to be rewritten. add an rm -f for junk.c to avoid weird Cygwin bug with cp -f onto an existing file. Sort list of auto-detected functions and eliminate unused checks for stpcpy, setlocale and getwd. Add autodetection of Cygwin scanf problems BETA: Rewrite section on configure to indicate what flags are important and what not. digest-doc.c, make-dump-id.c, profile.c, sorted-doc.c: Add proper decls for main(). make-msgfile.c: Document that this is old junk. Move proposal to text.c. make-msgfile.lex: Move proposal to text.c. make-mswin-unicode.pl: Convert error-generating code so that the entire message will be seen as a single unrecognized token. mule/mule-ccl.el: Update docs. lispref/mule.texi: Update CCL docs. ldap/eldap.c: Mule-ize. Use EXTERNAL_LIST_LOOP_2 instead of deleted EXTERNAL_LIST_LOOP. * XEmacs 21.5.18 "chestnut" is released. --------------------------------------------------------------- MULE-RELATED WORK: --------------------------------------------------------------- --------------------------- byte-char conversion --------------------------- buffer.c, buffer.h, insdel.c, text.c: Port FSF algorithm for byte-char conversion, replacing broken previous version. Track the char position of the gap. Add functions to do char-byte conversion downwards as well as upwards. Move comments about algorithm workings to internals manual. --------------------------- work on types --------------------------- alloc.c, console-x-impl.h, dump-data.c, dump-data.h, dumper.c, dialog-msw.c, dired-msw.c, doc.c, editfns.c, esd.c, event-gtk.h, event-msw.c, events.c, file-coding.c, file-coding.h, fns.c, glyphs-eimage.c, glyphs-gtk.c, glyphs-msw.c, glyphs-shared.c, glyphs-x.c, glyphs.c, glyphs.h, gui.c, hpplay.c, imgproc.c, intl-win32.c, lrecord.h, lstream.c, keymap.c, lisp.h, libsst.c, linuxplay.c, miscplay.c, miscplay.h, mule-coding.c, nas.c, nt.c, ntheap.c, ntplay.c, objects-msw.c, objects-tty.c, objects-x.c, print.c, process-nt.c, process.c, redisplay.h, select-common.h, select-gtk.c, select-x.c, sgiplay.c, sound.c, sound.h, sunplay.c, sysfile.h, sysdep.c, syswindows.h, text.c, unexnt.c, win32.c, xgccache.c: Further work on types. This creates a full set of types for all the basic semantics of `char' that I have so far identified, so that its semantics can always be identified for the purposes of proper Mule-safe code, and the raw use of `char' always avoided. (1) More type renaming, for consistency of naming. Char_ASCII -> Ascbyte UChar_ASCII -> UAscbyte Char_Binary -> CBinbyte UChar_Binary -> Binbyte SChar_Binary -> SBinbyte (2) Introduce Rawbyte, CRawbyte, Boolbyte, Chbyte, UChbyte, and Bitbyte and use them. (3) New types Itext, Wexttext and Textcount for separating out the concepts of bytes and textual units (different under UTF-16 and UTF-32, which are potential internal encodings). (4) qxestr*_c -> qxestr*_ascii. lisp.h: New; goes with other qxe() functions. #### Maybe goes in a different section. lisp.h: Group generic int-type defs together with EMACS_INT defs. lisp.h: * lisp.h (WEXTTEXT_IS_WIDE) New defns. lisp.h: New type to replace places where int occurs as a boolean. It's signed because occasionally people may want to use -1 as an error value, and because unsigned ints are viral -- see comments in the internals manual against using them. dynarr.c: int -> Bytecount. --------------------------- Mule-izing --------------------------- device-x.c: Partially Mule-ize. dumper.c, dumper.h: Mule-ize. Use Rawbyte. Use stderr_out not printf. Use wext_*(). sysdep.c, syswindows.h, text.c: New Wexttext API for manipulation of external text that may be Unicode (e.g. startup code under Windows). emacs.c: Mule-ize. Properly deal with argv in external encoding. Use wext_*() and Wexttext. Use Rawbyte. #if 0 some old junk on SCO that is unlikely to be correct. Rewrite allocation code in run-temacs. emacs.c, symsinit.h, win32.c: Rename win32 init function and call it even earlier, to initialize mswindows_9x_p even earlier, for use in startup code (XEUNICODE_P). process.c: Use _wenviron not environ under Windows, to get Unicode environment variables. event-Xt.c: Mule-ize drag-n-drop related stuff. dragdrop.c, dragdrop.h, frame-x.c: Mule-ize. text.h: Add some more stand-in defines for particular kinds of conversion; use in Mule-ization work in frame-x.c etc. --------------------------- Freshening --------------------------- intl-auto-encap-win32.c, intl-auto-encap-win32.h: Regenerate. --------------------------- Unicode-work --------------------------- intl-win32.c, syswindows.h: Factor out common options to MultiByteToWideChar and WideCharToMultiByte. Add convert_unicode_to_multibyte_malloc() and convert_unicode_to_multibyte_dynarr() and use. Add stuff for alloca() conversion of multibyte/unicode. alloc.c: Use dfc_external_data_len() in case of unicode coding system. alloc.c, mule-charset.c: Don't zero out and reinit charset Unicode tables. This fucks up dump-time loading. Anyway, either we load them at dump time or run time, never both. unicode.c: Dump the blank tables as well. --------------------------------------------------------------- DOCUMENTATION, MOSTLY MULE-RELATED: --------------------------------------------------------------- EmacsFrame.c, emodules.c, event-Xt.c, fileio.c, input-method-xlib.c, mule-wnnfns.c, redisplay-gtk.c, redisplay-tty.c, redisplay-x.c, regex.c, sysdep.c: Add comment about Mule work needed. text.h: Add more documentation describing why DFC routines were not written to return their value. Add some other DFC documentation. console-msw.c, console-msw.h: Add pointer to docs in win32.c. emacs.c: Add comments on sources of doc info. text.c, charset.h, unicode.c, intl-win32.c, intl-encap-win32.c, text.h, file-coding.c, mule-coding.c: Collect background comments and related to text matters and internationalization, and proposals for work to be done, in text.c or Internals manual, stuff related to specific textual API's in text.h, and stuff related to internal implementation of Unicode conversion in unicode.c. Put lots of pointers to the comments to make them easier to find. s/mingw32.h, s/win32-common.h, s/win32-native.h, s/windowsnt.h, win32.c: Add bunches of new documentation on the different kinds of builds and environments under Windows and how they work. Collect this info in win32.c. Add pointers to these docs in the relevant s/* files. emacs.c: Document places with long comments. Remove comment about exiting, move to internals manual, put in pointer. event-stream.c: Move docs about event queues and focus to internals manual, put in pointer. events.h: Move docs about event stream callbacks to internals manual, put in pointer. profile.c, redisplay.c, signal.c: Move documentation to the Internals manual. process-nt.c: Add pointer to comment in win32-native.el. lisp.h: Add comments about some comment conventions. lisp.h: Add comment about the second argument. device-msw.c, redisplay-msw.c: @@#### comments are out-of-date. --------------------------------------------------------------- PDUMP WORK (MOTIVATED BY UNICODE CHANGES) --------------------------------------------------------------- alloc.c, buffer.c, bytecode.c, console-impl.h, console.c, device.c, dumper.c, lrecord.h, elhash.c, emodules.h, events.c, extents.c, frame.c, glyphs.c, glyphs.h, mule-charset.c, mule-coding.c, objects.c, profile.c, rangetab.c, redisplay.c, specifier.c, specifier.h, window.c, lstream.c, file-coding.h, file-coding.c: PDUMP: Properly implement dump_add_root_block(), which never worked before, and is necessary for dumping Unicode tables. Pdump name changes for accuracy: XD_STRUCT_PTR -> XD_BLOCK_PTR. XD_STRUCT_ARRAY -> XD_BLOCK_ARRAY. XD_C_STRING -> XD_ASCII_STRING. *_structure_* -> *_block_*. lrecord.h: some comments added about dump_add_root_block() vs dump_add_root_block_ptr(). extents.c: remove incorrect comment about pdump problems with gap array. --------------------------------------------------------------- ALLOCATION --------------------------------------------------------------- abbrev.c, alloc.c, bytecode.c, casefiddle.c, device-msw.c, device-x.c, dired-msw.c, doc.c, doprnt.c, dragdrop.c, editfns.c, emodules.c, file-coding.c, fileio.c, filelock.c, fns.c, glyphs-eimage.c, glyphs-gtk.c, glyphs-msw.c, glyphs-x.c, gui-msw.c, gui-x.c, imgproc.c, intl-win32.c, lread.c, menubar-gtk.c, menubar.c, nt.c, objects-msw.c, objects-x.c, print.c, process-nt.c, process-unix.c, process.c, realpath.c, redisplay.c, search.c, select-common.c, symbols.c, sysdep.c, syswindows.h, text.c, text.h, ui-byhand.c: New macros {alloca,xnew}_{itext,{i,ext,raw,bin,asc}bytes} for more convenient allocation of these commonly requested items. Modify functions to use alloca_ibytes, alloca_array, alloca_extbytes, xnew_ibytes, etc. also XREALLOC_ARRAY, xnew. alloc.c: Rewrite the allocation functions to factor out repeated code. Add assertions for freeing dumped data. lisp.h: Moved down and consolidated with other allocation stuff. lisp.h, dynarr.c: New functions for allocation that's very efficient when mostly in LIFO order. lisp.h, text.c, text.h: Factor out some stuff for general use by alloca()-conversion funs. text.h, lisp.h: Fill out convenience routines for allocating various kinds of bytes and put them in lisp.h. Use them in place of xmalloc(), ALLOCA(). text.h: Fill out the convenience functions so the _MALLOC() kinds match the alloca() kinds. --------------------------------------------------------------- ERROR-CHECKING --------------------------------------------------------------- text.h: Create ASSERT_ASCTEXT_ASCII() and ASSERT_ASCTEXT_ASCII_LEN() from similar Eistring checkers and change the Eistring checkers to use them instead. --------------------------------------------------------------- MACROS IN LISP.H --------------------------------------------------------------- lisp.h: Redo GCPRO declarations. Create a "base" set of functions that can be used to generate any kind of gcpro sets -- regular, ngcpro, nngcpro, private ones used in GC_EXTERNAL_LIST_LOOP_2. buffer.c, callint.c, chartab.c, console-msw.c, device-x.c, dialog-msw.c, dired.c, extents.c, ui-gtk.c, rangetab.c, nt.c, mule-coding.c, minibuf.c, menubar-msw.c, menubar.c, menubar-gtk.c, lread.c, lisp.h, gutter.c, glyphs.c, glyphs-widget.c, fns.c, fileio.c, file-coding.c, specifier.c: Eliminate EXTERNAL_LIST_LOOP, which does not check for circularities. Use EXTERNAL_LIST_LOOP_2 instead or EXTERNAL_LIST_LOOP_3 or EXTERNAL_PROPERTY_LIST_LOOP_3 or GC_EXTERNAL_LIST_LOOP_2 (new macro). Removed/redid comments on EXTERNAL_LIST_LOOP. --------------------------------------------------------------- SPACING FIXES --------------------------------------------------------------- callint.c, hftctl.c, number-gmp.c, process-unix.c: Spacing fixes. --------------------------------------------------------------- FIX FOR GEOMETRY PROBLEM IN FIRST FRAME --------------------------------------------------------------- unicode.c: Add workaround for newlib bug in sscanf() [should be fixed by release 1.5.12 of Cygwin]. toolbar.c: bug fix for problem of initial frame being 77 chars wide on Windows. will be overridden by my other ws. --------------------------------------------------------------- FIX FOR LEAKING PROCESS HANDLES: --------------------------------------------------------------- process-nt.c: Fixes for leaking handles. Inspired by work done by Adrian Aichner <adrian@xemacs.org>. --------------------------------------------------------------- FIX FOR CYGWIN BUG (Unicode-related): --------------------------------------------------------------- unicode.c: Add workaround for newlib bug in sscanf() [should be fixed by release 1.5.12 of Cygwin]. --------------------------------------------------------------- WARNING FIXES: --------------------------------------------------------------- console-stream.c: `reinit' is unused. compiler.h, event-msw.c, frame-msw.c, intl-encap-win32.c, text.h: Add stuff to deal with ANSI-aliasing warnings I got. regex.c: Gather includes together to avoid warning. --------------------------------------------------------------- CHANGES TO INITIALIZATION ROUTINES: --------------------------------------------------------------- buffer.c, emacs.c, console.c, debug.c, device-x.c, device.c, dragdrop.c, emodules.c, eval.c, event-Xt.c, event-gtk.c, event-msw.c, event-stream.c, event-tty.c, events.c, extents.c, faces.c, file-coding.c, fileio.c, font-lock.c, frame-msw.c, glyphs-widget.c, glyphs.c, gui-x.c, insdel.c, lread.c, lstream.c, menubar-gtk.c, menubar-x.c, minibuf.c, mule-wnnfns.c, objects-msw.c, objects.c, print.c, scrollbar-x.c, search.c, select-x.c, text.c, undo.c, unicode.c, window.c, symsinit.h: Call reinit_*() functions directly from emacs.c, for clarity. Factor out some redundant init code. Move disallowed stuff that had crept into vars_of_glyphs() into complex_vars_of_glyphs(). Call init_eval_semi_early() from eval.c not in the middle of vars_of_() in emacs.c since there should be no order dependency in the latter calls. --------------------------------------------------------------- ARMAGEDDON: --------------------------------------------------------------- alloc.c, emacs.c, lisp.h, print.c: Rename inhibit_non_essential_printing_operations to inhibit_non_essential_conversion_operations. text.c: Assert on !inhibit_non_essential_conversion_operations. console-msw.c, print.c: Don't do conversion in SetConsoleTitle or FindWindow to avoid problems during armageddon. Put #errors for NON_ASCII_INTERNAL_FORMAT in places where problems would arise. --------------------------------------------------------------- CHANGES TO THE BUILD PROCEDURE: --------------------------------------------------------------- config.h.in, s/cxux.h, s/usg5-4-2.h, m/powerpc.h: Add comment about correct ordering of this file. Rearrange everything to follow this -- put all #undefs together and before the s&m files. Add undefs for HAVE_ALLOCA, C_ALLOCA, BROKEN_ALLOCA_IN_FUNCTION_CALLS, STACK_DIRECTION. Remove unused HAVE_STPCPY, HAVE_GETWD, HAVE_SETLOCALE. m/gec63.h: Deleted; totally broken, not used at all, not in FSF. m/7300.h, m/acorn.h, m/alliant-2800.h, m/alliant.h, m/altos.h, m/amdahl.h, m/apollo.h, m/att3b.h, m/aviion.h, m/celerity.h, m/clipper.h, m/cnvrgnt.h, m/convex.h, m/cydra5.h, m/delta.h, m/delta88k.h, m/dpx2.h, m/elxsi.h, m/ews4800r.h, m/gould.h, m/hp300bsd.h, m/hp800.h, m/hp9000s300.h, m/i860.h, m/ibmps2-aix.h, m/ibmrs6000.h, m/ibmrt-aix.h, m/ibmrt.h, m/intel386.h, m/iris4d.h, m/iris5d.h, m/iris6d.h, m/irist.h, m/isi-ov.h, m/luna88k.h, m/m68k.h, m/masscomp.h, m/mg1.h, m/mips-nec.h, m/mips-siemens.h, m/mips.h, m/news.h, m/nh3000.h, m/nh4000.h, m/ns32000.h, m/orion105.h, m/pfa50.h, m/plexus.h, m/pmax.h, m/powerpc.h, m/pyrmips.h, m/sequent-ptx.h, m/sequent.h, m/sgi-challenge.h, m/symmetry.h, m/tad68k.h, m/tahoe.h, m/targon31.h, m/tekxd88.h, m/template.h, m/tower32.h, m/tower32v3.h, m/ustation.h, m/vax.h, m/wicat.h, m/xps100.h: Delete C_ALLOCA, HAVE_ALLOCA, STACK_DIRECTION, BROKEN_ALLOCA_IN_FUNCTION_CALLS. All of this is auto-detected. When in doubt, I followed recent FSF sources, which also have these things deleted.
author ben
date Thu, 04 Nov 2004 23:08:28 +0000
parents 13a418960a88
children ad2f4ae9895b
line wrap: on
line source

/* Widget-specific glyph objects.
   Copyright (C) 1998, 1999, 2000, 2002 Andy Piper.
   Copyright (C) 2003 Ben Wing.

This file is part of XEmacs.

XEmacs is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

XEmacs is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with XEmacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* Synched up with: Not in FSF. */

/* written by Andy Piper <andy@xemacs.org> */

#include <config.h>
#include "lisp.h"

#include "bytecode.h"
#include "console.h"
#include "device-impl.h"
#include "faces.h"
#include "frame.h"
#include "glyphs.h"
#include "gui.h"
#include "insdel.h"
#include "lstream.h"
#include "objects.h"
#include "opaque.h"
#include "window.h"

DEFINE_IMAGE_INSTANTIATOR_FORMAT (button);
DEFINE_IMAGE_INSTANTIATOR_FORMAT (combo_box);
Lisp_Object Qcombo_box;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (edit_field);
Lisp_Object Qedit_field;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (scrollbar);
Lisp_Object Qscrollbar;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (widget);
DEFINE_IMAGE_INSTANTIATOR_FORMAT (label);
Lisp_Object Qlabel;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (progress_gauge);
Lisp_Object Qprogress_gauge;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (tree_view);
Lisp_Object Qtree_view;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (tab_control);
Lisp_Object Qtab_control;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (layout);
Lisp_Object Qlayout;
DEFINE_IMAGE_INSTANTIATOR_FORMAT (native_layout);
Lisp_Object Qnative_layout;

Lisp_Object Qetched_in, Qetched_out, Qbevel_in, Qbevel_out;
Lisp_Object Qmake_glyph;
Lisp_Object Vwidget_border_width;

static int widget_border_width (Lisp_Object domain);
static int widget_spacing (Lisp_Object domain);
static void widget_query_string_geometry (Lisp_Object string, Lisp_Object face,
					  int *width, int *height, Lisp_Object domain);

#define BORDER_FIDDLE_FACTOR 10
#ifdef DEBUG_WIDGETS
int debug_widget_instances;
#endif

/* TODO:
   - tooltips for controls, especially buttons.
   - keyboard traversal.
   - lisp configurable layout.
 */

/* In MS-Windows normal windows work in pixels, dialog boxes work in
   dialog box units. Why? sigh. We could reuse the metrics for dialogs
   if this were not the case. As it is we have to position things
   pixel wise. I'm not even sure that X has this problem at least for
   buttons in groups. */
static int
widget_possible_dest_types (void)
{
  return IMAGE_WIDGET_MASK;
}

static void
check_valid_instantiator (Lisp_Object data)
{
  Lisp_Object glyph = data;
  if (SYMBOLP (data))
    glyph = XSYMBOL (data)->value;

  if (!CONSP (glyph) && !VECTORP (glyph))
    invalid_argument ("instantiator item must be a vector", data);
}

static void
check_valid_orientation (Lisp_Object data)
{
  if (!EQ (data, Qhorizontal)
      &&
      !EQ (data, Qvertical))
    invalid_constant ("unknown orientation for layout", data);
}

static void
check_valid_tab_orientation (Lisp_Object data)
{
  if (!EQ (data, Qtop)
      &&
      !EQ (data, Qbottom)
      &&
      !EQ (data, Qleft)
      &&
      !EQ (data, Qright))
    invalid_constant ("unknown orientation for tab control", data);
}

static void
check_valid_justification (Lisp_Object data)
{
  if (!EQ (data, Qleft) 
      && 
      !EQ (data, Qright) 
      && 
      !EQ (data, Qtop) 
      && 
      !EQ (data, Qbottom) 
      && 
      !EQ (data, Qcenter))
    invalid_constant ("unknown justification for layout", data);
}

static void
check_valid_border (Lisp_Object data)
{
  if (!EQ (data, Qt) && !EQ (data, Qetched_in) && !EQ (data, Qetched_out)
      && !EQ (data, Qbevel_in) && !EQ (data, Qbevel_out)
      && !GLYPHP (data) && !VECTORP (data))
    invalid_argument ("unknown border style for layout", data);
}

static void
check_valid_anything (Lisp_Object UNUSED (data))
{
}

static void
check_valid_callback (Lisp_Object data)
{
    if (!SYMBOLP (data)
	&& !COMPILED_FUNCTIONP (data)
	&& !CONSP (data))
    {
	invalid_argument (":callback must be a function or expression", data);
    }
}

static void
check_valid_int_or_function (Lisp_Object data)
{
  if (!INTP (data) && !CONSP (data) && !SYMBOLP (data))
    invalid_argument ("must be an integer or expresssion", data);
}

static void
check_valid_symbol (Lisp_Object data)
{
    CHECK_SYMBOL (data);
}

static void
check_valid_string_or_vector (Lisp_Object data)
{
    if (!STRINGP (data) && !VECTORP (data))
	invalid_argument (":descriptor must be a string or a vector", data);
}

static void
check_valid_item_list (Lisp_Object items)
{
  EXTERNAL_LIST_LOOP_2 (elt, items)
    {
      if (STRINGP (elt))
	CHECK_STRING (elt);
      else if (VECTORP (elt))
	gui_parse_item_keywords (elt);
      else if (LISTP (elt))
	check_valid_item_list (elt);
      else
	invalid_argument ("Item must be vector, list or string", elt);
    }
}

static void
check_valid_instantiator_list (Lisp_Object data)
{
  EXTERNAL_LIST_LOOP_2 (elt, data)
    {
      check_valid_instantiator (elt);
    }
}

static Lisp_Object
glyph_instantiator_to_glyph (Lisp_Object sym)
{
  /* This function calls lisp. */
  Lisp_Object glyph = sym;
  struct gcpro gcpro1;

  GCPRO1 (glyph);
  /* if we have a symbol get at the actual data */
  if (SYMBOLP (glyph))
    glyph = XSYMBOL (glyph)->value;

  if (CONSP (glyph))
    glyph = Feval (glyph);

  /* Be really helpful to the user. */
  if (VECTORP (glyph))
    {
      glyph = call1 (Qmake_glyph, glyph);
    }

  /* substitute the new glyph */
  RETURN_UNGCPRO (glyph);
}

static void
substitute_keyword_value (Lisp_Object inst, Lisp_Object key, Lisp_Object val)
{
  int i;
  /* substitute the new glyph */
  for (i = 0; i < XVECTOR_LENGTH (inst); i++)
    {
      if (EQ (key, XVECTOR_DATA (inst)[i]))
	{
	  XVECTOR_DATA (inst)[i+1] = val;
	  break;
	}
    }
}

/* Determine the border with of the widget. */
static int
widget_border_width (Lisp_Object domain)
{
  /* #### FIXME -- need to use specifiers (Vwidget_border_width) for
     some portion of this. */
  if (HAS_DEVMETH_P (DOMAIN_XDEVICE (domain),
		     widget_border_width))
    return DEVMETH (DOMAIN_XDEVICE (domain), widget_border_width, ());
  else 
    return DEFAULT_WIDGET_BORDER_WIDTH;
}

static int
widget_instance_border_width (Lisp_Image_Instance* ii)
{
  return widget_border_width (IMAGE_INSTANCE_DOMAIN (ii));
}

/* #### It's not clear to me what the value of logical_unit_height should
   be, or whether it should even depend on the current image_instance.  It
   really should probably only depend on the default widget face and the
   domain, however you can envisage users wanting different logical units
   for nested layouts - so using the properties of the current layout is
   probably not so dumb. */
static int
logical_unit_height (Lisp_Object text, Lisp_Object face, Lisp_Object domain)
{
  int charheight = 0;
  widget_query_string_geometry (text, face, 
				0, &charheight, domain);
  /* For the returned value to be useful it needs to be big enough to
     accomodate the largest single-height widget.  This is currently
     the edit-field. */
  return charheight + 2 * widget_spacing (domain)
    + 4 * widget_border_width (domain);
}

static int
widget_logical_unit_height (Lisp_Image_Instance* ii)
{
  return logical_unit_height (NILP (IMAGE_INSTANCE_WIDGET_TEXT (ii)) ?
			      NILP (IMAGE_INSTANCE_NAME (ii)) ?
			      Fsymbol_name (Qwidget) 
			      : IMAGE_INSTANCE_NAME (ii)
			      : IMAGE_INSTANCE_WIDGET_TEXT (ii),
			      IMAGE_INSTANCE_WIDGET_FACE (ii),
			      IMAGE_INSTANCE_DOMAIN (ii));
}

/* Wire widget property invocations to specific widgets. The problem
   we are solving here is that when instantiators get converted to
   instances they lose some type information (they just become
   subwindows or widgets for example). For widgets we need to preserve
   this type information so that we can do widget specific operations
   on the instances. This is encoded in the widget type
   field. widget_property gets invoked by decoding the primary type
   (Qwidget), <widget>_property then invokes based on the secondary
   type (Qedit_field for example). It is debatable whether we should
   wire things in this generalised way rather than treating widgets
   specially in image_instance_property. */
static Lisp_Object
widget_property (Lisp_Object image_instance, Lisp_Object prop)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (image_instance);
  struct image_instantiator_methods* meths;
#if 0				/* The usefulness of this is dubious. */
  /* first see if its a general property ... */
  if (!NILP (Fplist_member (IMAGE_INSTANCE_WIDGET_PROPS (ii), prop)))
    return Fplist_get (IMAGE_INSTANCE_WIDGET_PROPS (ii), prop, Qnil);
#endif
  /* .. then try device specific methods ... */
  meths = decode_device_ii_format (image_instance_device (image_instance),
				   IMAGE_INSTANCE_WIDGET_TYPE (ii),
				   ERROR_ME_NOT);
  if (meths && HAS_IIFORMAT_METH_P (meths, property))
    return IIFORMAT_METH (meths, property, (image_instance, prop));
  /* ... then format specific methods ... */
  meths = decode_device_ii_format (Qnil, IMAGE_INSTANCE_WIDGET_TYPE (ii),
				   ERROR_ME_NOT);
  if (meths && HAS_IIFORMAT_METH_P (meths, property))
    return IIFORMAT_METH (meths, property, (image_instance, prop));
  /* ... then fail */
  return Qunbound;
}

/* Update the displayed properties of a widget.

   #### This has been adapted from the original set_property functions
   and thus reuses the state management of that. A better solution is
   to simply re-parse the instantiator when items need updating. This
   make comparing differences much simpler and obviates the need for a
   lot of the state variables.

   #### property is still a valid function since we have to be able to
   extract information from the actual widget.

   #### update_widget should probably be re-written to use the
   instantiator. We probably want to keep a record of the differences
   also to make this easy. We would also need a pending_instantiator
   so that changes could be delayed. */
static void
widget_update (Lisp_Object image_instance, Lisp_Object instantiator)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (image_instance);
  struct image_instantiator_methods* meths;
  struct gcpro gcpro1;

  Lisp_Object text = find_keyword_in_vector (instantiator, Q_text);
  Lisp_Object desc = find_keyword_in_vector (instantiator, Q_descriptor);
  Lisp_Object items = find_keyword_in_vector (instantiator, Q_items);
  Lisp_Object descriptor_item = Qnil;

  GCPRO1 (descriptor_item);

  /* Pick up any generic properties that we might need to keep hold
     of. 
     #### This is potentially bogus because it is changing the items
     in place rather than in the pending items. */
  if (!NILP (text))
    {
      IMAGE_INSTANCE_WIDGET_TEXT (ii) = text;
      IMAGE_INSTANCE_TEXT_CHANGED (ii) = 1;
    }

  /* Retrieve the gui item information. This is easy if we have been
     provided with a vector, more difficult if we have just been given
     keywords.

     #### This is inconsistent with instantiation in that you have to
     have the :descriptor keyword for updates in order to recognise 
     changes. */
  if (VECTORP (desc))
    {
      descriptor_item = gui_parse_item_keywords_no_errors (desc);
    }
  else
    {
      /* Since we are updating the instantiator could be incomplete
	 and hence the gui item descriptor not well formed. We
	 therefore try updating and discard the results if nothing
	 changed. */
      descriptor_item = copy_gui_item (IMAGE_INSTANCE_WIDGET_ITEM (ii));
      if (!update_gui_item_keywords (descriptor_item, instantiator))
	descriptor_item = Qnil;
    }

  /* Record new items for update. *_redisplay will do the
     rest. */
  if (!EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qlayout)
      && 
      !EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qnative_layout))
    {
      if (!NILP (items))
	{
	  if (NILP (descriptor_item))
	    descriptor_item = IMAGE_INSTANCE_WIDGET_ITEM (ii);
	  
	  check_valid_item_list (items);
#ifdef DEBUG_WIDGET_OUTPUT
	  stderr_out ("items for widget %p updated\n", 
		      IMAGE_INSTANCE_SUBWINDOW_ID (ii));
#endif
	  /* Don't set the actual items since we might decide not to use
	     the new ones (because nothing has really changed). If we did
	     set them and didn't use them then we would get into whole
	     heaps of trouble when the old items get GC'd. */
	  descriptor_item = Fcons (descriptor_item, parse_gui_item_tree_children (items));
	}
      /* If the descriptor was updated but not the items we need to fill
	 in the `new' items. */
      else if (!NILP (descriptor_item) 
	       && 
	       CONSP (IMAGE_INSTANCE_WIDGET_ITEMS (ii)))
	{
	  descriptor_item = Fcons 
	    (descriptor_item,
	     copy_gui_item_tree (XCDR (IMAGE_INSTANCE_WIDGET_ITEMS (ii))));
	}
    }

  if (!NILP (descriptor_item))
    {
      IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii) = descriptor_item;
      IMAGE_INSTANCE_WIDGET_ITEMS_CHANGED (ii) = 1;
    }

  UNGCPRO;
      
  /* Now try device specific methods first ... */
  meths = decode_device_ii_format (image_instance_device (image_instance),
				   IMAGE_INSTANCE_WIDGET_TYPE (ii),
				   ERROR_ME_NOT);
  MAYBE_IIFORMAT_METH (meths, update, (image_instance, instantiator));
  /* ... then format specific methods ... */
  meths = decode_device_ii_format (Qnil, IMAGE_INSTANCE_WIDGET_TYPE (ii),
				   ERROR_ME_NOT);
  MAYBE_IIFORMAT_METH (meths, update, (image_instance, instantiator));
#if 0 /* The usefulness of this is dubious. */
  /* we didn't do any device specific properties, so shove the property in our plist. */
  IMAGE_INSTANCE_WIDGET_PROPS (ii)
    = Fplist_put (IMAGE_INSTANCE_WIDGET_PROPS (ii), prop, val);
#endif
}

/* Like the rest of redisplay, we want widget updates to occur
   asynchronously. Thus toolkit specific methods for setting
   properties must be called by redisplay instead of by *_update. Thus
   *_update records the change and this function actually implements
   it. We want to be slightly clever about this however by supplying
   format specific functions for the updates instead of lumping them
   all into this function. Note that there is no need for format
   generic functions. This is not the same as widget_update! */
void
redisplay_widget (Lisp_Object widget)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (widget);
  struct image_instantiator_methods* meths;

  if (!WIDGET_IMAGE_INSTANCEP (widget)
      || EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qlayout)
      || EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qnative_layout))
    return;

  /* Device-format specific methods - e.g. x_tab_control_redisplay () */
  meths = decode_device_ii_format (image_instance_device (widget), 
				   IMAGE_INSTANCE_WIDGET_TYPE (ii), 
				   ERROR_ME_NOT);
  MAYBE_IIFORMAT_METH (meths, redisplay, (widget));

  /* Device generic methods - e.g. x_redisplay_widget (). We must
     update the widget's size as it may have been changed by the the
     layout routines. We also do this here so that explicit resizing
     from lisp does not result in synchronous updates. Do this last so
     that format-specific methods have an opportunity to prevent
     wholesale changes - e.g. rebuilding tabs. */
  MAYBE_DEVMETH (DOMAIN_XDEVICE (IMAGE_INSTANCE_DOMAIN (ii)),
		 redisplay_widget, (ii));

  /* Pick up the items we recorded earlier. */
  if (IMAGE_INSTANCE_WIDGET_ITEMS_CHANGED (ii))
    {
      IMAGE_INSTANCE_WIDGET_ITEMS (ii) =
	IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii);
      IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii) = Qnil;
    }
}

static void
widget_query_string_geometry (Lisp_Object string, Lisp_Object face,
			      int *width, int *height, Lisp_Object domain)
{
  struct device *d = DOMAIN_XDEVICE (domain);

  if (HAS_DEVMETH_P (d, widget_query_string_geometry))
    DEVMETH (d, widget_query_string_geometry,
	     (string, face, width, height, domain));
  else
    query_string_geometry (string, face, width, height, 0, domain);
    
}

/* Determine the spacing of the widget. */
static int
widget_spacing (Lisp_Object domain)
{
  if (HAS_DEVMETH_P (DOMAIN_XDEVICE (domain), widget_spacing))
    return DEVMETH (DOMAIN_XDEVICE (domain),
		    widget_spacing, (0));
  else 
    return DEFAULT_WIDGET_SPACING;
}

/* Query for a widgets desired geometry. If no type specific method is
   provided then use the widget text to calculate sizes. */
static void
widget_query_geometry (Lisp_Object image_instance,
		       int* width, int* height,
		       enum image_instance_geometry disp, Lisp_Object domain)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (image_instance);
  struct image_instantiator_methods* meths;
  Lisp_Object dynamic_width = Qnil;
  Lisp_Object dynamic_height = Qnil;

  /* First just set up what we already have. */
  if (width)	*width = IMAGE_INSTANCE_WIDTH (ii);
  if (height)	*height = IMAGE_INSTANCE_HEIGHT (ii);

  if (IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii)
      ||
      IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
    {
      /* .. then try device specific methods ... */
      meths = decode_device_ii_format (image_instance_device (image_instance),
				       IMAGE_INSTANCE_WIDGET_TYPE (ii),
				       ERROR_ME_NOT);
      if (meths && HAS_IIFORMAT_METH_P (meths, query_geometry))
	IIFORMAT_METH (meths, query_geometry, (image_instance,
					       width, height, disp,
					       domain));
      else
	{
	  /* ... then format specific methods ... */
	  meths = decode_device_ii_format (Qnil, IMAGE_INSTANCE_WIDGET_TYPE (ii),
					   ERROR_ME_NOT);
	  if (meths && HAS_IIFORMAT_METH_P (meths, query_geometry))
	    IIFORMAT_METH (meths, query_geometry, (image_instance,
						   width, height, disp,
						   domain));
	  else
	    {
	      int w, h;

	      /* Then if we are allowed to resize the widget, make the
		 size the same as the text dimensions. */
	      widget_query_string_geometry (IMAGE_INSTANCE_WIDGET_TEXT (ii),
					    IMAGE_INSTANCE_WIDGET_FACE (ii),
					    &w, &h, domain);
	      /* Adjust the size for borders. */
	      if (IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
		*width = w + 2 * widget_instance_border_width (ii);
	      if (IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii))
		*height = h +  2 * widget_instance_border_width (ii);
	    }
	}
      /* Finish off with dynamic sizing. */
      if (!NILP (IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii)))
	{
	  dynamic_width =
	    eval_within_redisplay (IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii));
	  if (INTP (dynamic_width))
	    *width = XINT (dynamic_width);
	}
      if (!NILP (IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii)))
	{
	  dynamic_height =
	    eval_within_redisplay (IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii));
	  if (INTP (dynamic_height))
	    *height = XINT (dynamic_height);
	}
    }
}

static int
widget_layout (Lisp_Object image_instance,
	       int width, int height, int xoffset, int yoffset,
	       Lisp_Object domain)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (image_instance);
  struct image_instantiator_methods* meths;

  /* .. then try device specific methods ... */
  meths = decode_device_ii_format (image_instance_device (image_instance),
				   IMAGE_INSTANCE_WIDGET_TYPE (ii),
				   ERROR_ME_NOT);
  if (meths && HAS_IIFORMAT_METH_P (meths, layout))
    return IIFORMAT_METH (meths, layout, (image_instance,
					  width, height, xoffset, yoffset,
					  domain));
  else
    {
      /* ... then format specific methods ... */
      meths = decode_device_ii_format (Qnil, IMAGE_INSTANCE_WIDGET_TYPE (ii),
				       ERROR_ME_NOT);
      if (meths && HAS_IIFORMAT_METH_P (meths, layout))
	return IIFORMAT_METH (meths, layout, (image_instance,
					      width, height, xoffset, yoffset,
					      domain));
    }
  return 1;
}

static void
widget_validate (Lisp_Object instantiator)
{
  Lisp_Object desc = find_keyword_in_vector (instantiator, Q_descriptor);

  if (NILP (desc))
    invalid_argument ("Must supply :descriptor", instantiator);

  if (VECTORP (desc))
    gui_parse_item_keywords (desc);

  if (!NILP (find_keyword_in_vector (instantiator, Q_width))
      && !NILP (find_keyword_in_vector (instantiator, Q_pixel_width)))
    invalid_argument ("Must supply only one of :width and :pixel-width", instantiator);

  if (!NILP (find_keyword_in_vector (instantiator, Q_height))
	     && !NILP (find_keyword_in_vector (instantiator, Q_pixel_height)))
    invalid_argument ("Must supply only one of :height and :pixel-height", instantiator);
}

static void
combo_box_validate (Lisp_Object instantiator)
{
  widget_validate (instantiator);
  if (NILP (find_keyword_in_vector (instantiator, Q_items)))
    invalid_argument ("Must supply item list", instantiator);
}

/* we need to convert things like glyphs to images, eval expressions
   etc.*/
static Lisp_Object
widget_normalize (Lisp_Object inst, Lisp_Object UNUSED (console_type),
		  Lisp_Object UNUSED (dest_mask))
{
  /* This function can call lisp */
  Lisp_Object glyph = find_keyword_in_vector (inst, Q_image);

  /* we need to eval glyph if its an expression, we do this for the
     same reasons we normalize file to data.

     #### should just normalize the data. */
  if (!NILP (glyph))
    {
      substitute_keyword_value (inst, Q_image,
				glyph_instantiator_to_glyph (glyph));
    }

  return inst;
}

static void
initialize_widget_image_instance (Lisp_Image_Instance *ii, Lisp_Object type)
{
  /*  initialize_subwindow_image_instance (ii);*/
  IMAGE_INSTANCE_WIDGET_TYPE (ii) = type;
  IMAGE_INSTANCE_WIDGET_PROPS (ii) = Qnil;
  SET_IMAGE_INSTANCE_WIDGET_FACE (ii, Qnil);
  IMAGE_INSTANCE_WIDGET_ITEMS (ii) = allocate_gui_item ();
  IMAGE_INSTANCE_LAYOUT_CHILDREN (ii) = Qnil;
  IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii) = Qnil;
  IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii) = Qnil;
  IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii) = Qnil;
  IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii) = 1;
  IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii) = 1;
  IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) = LAYOUT_HORIZONTAL;
  IMAGE_INSTANCE_SUBWINDOW_H_JUSTIFY (ii) = 0;
  IMAGE_INSTANCE_SUBWINDOW_V_JUSTIFY (ii) = 0;
}

/* Instantiate a button widget. Unfortunately instantiated widgets are
   particular to a frame since they need to have a parent. It's not
   like images where you just select the image into the context you
   want to display it in and BitBlt it. So image instances can have a
   many-to-one relationship with things you see, whereas widgets can
   only be one-to-one (i.e. per frame) */
void
widget_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
		    Lisp_Object pointer_fg, Lisp_Object pointer_bg,
		    int dest_mask, Lisp_Object domain)
{
  /* #### practically all of this should be moved to widget_update()
     so that users can dynamically change all possible widget
     properties. */
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object face = find_keyword_in_vector (instantiator, Q_face);
  Lisp_Object height = find_keyword_in_vector (instantiator, Q_height);
  Lisp_Object width = find_keyword_in_vector (instantiator, Q_width);
  Lisp_Object pixwidth = find_keyword_in_vector (instantiator, Q_pixel_width);
  Lisp_Object pixheight = find_keyword_in_vector (instantiator, Q_pixel_height);
  Lisp_Object desc = find_keyword_in_vector (instantiator, Q_descriptor);
  Lisp_Object glyph = find_keyword_in_vector (instantiator, Q_image);
  Lisp_Object items = find_keyword_in_vector (instantiator, Q_items);
  Lisp_Object orient = find_keyword_in_vector (instantiator, Q_orientation);
  Lisp_Object mwidth = find_keyword_in_vector (instantiator, Q_margin_width);
  Lisp_Object ifocus = find_keyword_in_vector (instantiator, Q_initial_focus);
  int pw=0, ph=0, tw=0, th=0;

  /* this just does pixel type sizing */
  subwindow_instantiate (image_instance, instantiator, pointer_fg, pointer_bg,
			 dest_mask, domain);

  if (!(dest_mask & IMAGE_WIDGET_MASK))
    incompatible_image_types (instantiator, dest_mask, IMAGE_WIDGET_MASK);

  initialize_widget_image_instance (ii, XVECTOR_DATA (instantiator)[0]);

  IMAGE_INSTANCE_TYPE (ii) = IMAGE_WIDGET;

  /* retrieve the fg and bg colors */
  if (!NILP (face))
    SET_IMAGE_INSTANCE_WIDGET_FACE (ii, Fget_face (face));

  /* Retrieve the gui item information. This is easy if we have been
     provided with a vector, more difficult if we have just been given
     keywords. Note that standard gui descriptor shortcuts will not work
     because of keyword parsing.

     #### This is bogus in that descriptor and items share the same slot, 
     we should rationalize. */
  if (VECTORP (desc))
    {
      IMAGE_INSTANCE_WIDGET_ITEMS (ii) =
	gui_parse_item_keywords_no_errors (desc);
    }
  else
    {
      /* big cheat - we rely on the fact that a gui item looks like an instantiator */
      IMAGE_INSTANCE_WIDGET_ITEMS (ii) =
	widget_gui_parse_item_keywords (instantiator);
    }

  /* Pick up the orientation before we do our first layout. */
  if (EQ (orient, Qleft) || EQ (orient, Qright) || EQ (orient, Qvertical))
    IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) = LAYOUT_VERTICAL;

  /* parse more gui items out of the properties */
  if (!NILP (items) && !EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qlayout)
      && !EQ (IMAGE_INSTANCE_WIDGET_TYPE (ii), Qnative_layout))
    {
      IMAGE_INSTANCE_WIDGET_ITEMS (ii) =
	Fcons (IMAGE_INSTANCE_WIDGET_ITEMS (ii),
	       parse_gui_item_tree_children (items));
    }

  /* Normalize size information. We now only assign sizes if the user
     gives us some explicitly, or there are some constraints that we
     can't change later on. Otherwise we postpone sizing until query
     geometry gets called. */
  if (!NILP (pixwidth))		/* pixwidth takes precendent */
    {
      if (!INTP (pixwidth))
	IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii) = pixwidth;
      else
	{
	  pw = XINT (pixwidth);
	  IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii) = 0;
	}
    }
  else if (!NILP (width))
    {
      tw = XINT (width);
      IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii) = 0;
    }

  if (!NILP (pixheight))
    {
      if (!INTP (pixheight))
	IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii) = pixheight;
      else
	{
	  ph = XINT (pixheight);
	  IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii) = 0;
	}
    }
  else if (!NILP (height) && XINT (height) > 1)
    {
      th = XINT (height);
      IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii) = 0;
    }

  /* Taking the default face information when the user has specified
     size in characters is probably as good as any since the widget
     face is more likely to be proportional and thus give inadequate
     results. Using character sizes can only ever be approximate
     anyway. :height is measured in logical characters which take into
     account the borders and spacing on widgets. */
  if (tw)
    {
      int charwidth;
      default_face_font_info (domain, 0, 0, 0, &charwidth, 0);
      pw = ROUND_UP (charwidth * tw + 4 * widget_instance_border_width (ii), charwidth);
    }

  /* For heights the widget face is more appropriate. */
  if (th == 1) 
    {
      int charheight;
      if (!NILP (IMAGE_INSTANCE_WIDGET_TEXT (ii))) 
	{
	  widget_query_string_geometry (IMAGE_INSTANCE_WIDGET_TEXT (ii),
					IMAGE_INSTANCE_WIDGET_FACE (ii),
					0, &charheight, domain);
	}
      else 
	{
	  default_face_font_info (domain, 0, 0, &charheight, 0, 0);
	}
      ph = (charheight + 2 * widget_instance_border_width (ii)) * th;
    }
  /* For heights > 1 use logical units. */
  else if (th > 1) 
    {
      ph = widget_logical_unit_height (ii) * th;
    }

  /* for a widget with an image pick up the dimensions from that */
  if (!NILP (glyph))
    {
      if (!pw)
	pw = glyph_width (glyph, image_instance) + 2 * widget_instance_border_width (ii);
      if (!ph)
	ph = glyph_height (glyph, image_instance) + 2 * widget_instance_border_width (ii);
      IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii) = 0;
      IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii) = 0;
    }

  /* Pick up the margin width. */
  if (!NILP (mwidth))
    IMAGE_INSTANCE_MARGIN_WIDTH (ii) = XINT (mwidth);

  IMAGE_INSTANCE_WANTS_INITIAL_FOCUS (ii) = !NILP (ifocus);

  /* Layout for the layout widget is premature at this point since the
     children will not have been instantiated. We can't instantiate
     them until the device instantiation method for the layout has
     been executed. We do however want to record any specified
     dimensions. */
  if (pw)	IMAGE_INSTANCE_WIDTH (ii) = pw;
  if (ph)	IMAGE_INSTANCE_HEIGHT (ii) = ph;
}

static void
widget_post_instantiate (Lisp_Object UNUSED (image_instance),
#ifdef DEBUG_WIDGETS
			 Lisp_Object instantiator,
#else
			 Lisp_Object UNUSED (instantiator),
#endif
			 Lisp_Object UNUSED (domain))
{
#ifdef DEBUG_WIDGETS
  debug_widget_instances++;
  stderr_out ("instantiated ");
  debug_print (instantiator);
  stderr_out ("%d widgets instantiated\n", debug_widget_instances);
#endif
}

/* Get the geometry of a button control. We need to adjust the size
   depending on the type of button. */
static void
button_query_geometry (Lisp_Object image_instance,
		       int* width, int* height,
		       enum image_instance_geometry UNUSED (disp),
		       Lisp_Object domain)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  int w, h;
  widget_query_string_geometry (IMAGE_INSTANCE_WIDGET_TEXT (ii),
				IMAGE_INSTANCE_WIDGET_FACE (ii),
				&w, &h, domain);
  /* Adjust the size for borders. */
  if (IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
    {
      *width = w + 3 * widget_instance_border_width (ii);

      if (EQ (XGUI_ITEM (IMAGE_INSTANCE_WIDGET_ITEM (ii))->style, Qradio)
	  ||
	  EQ (XGUI_ITEM (IMAGE_INSTANCE_WIDGET_ITEM (ii))->style, Qtoggle))
	/* This is an approximation to the size of the actual button bit. */
	*width += 12;
    }
  if (IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii))
    *height = h +  3 * widget_instance_border_width (ii);
}

/* Get the geometry of an edit field. */
static void
edit_field_query_geometry (Lisp_Object image_instance,
			   int* width, int* height,
			   enum image_instance_geometry UNUSED (disp),
			   Lisp_Object domain)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  int w, h;
  widget_query_string_geometry (IMAGE_INSTANCE_WIDGET_TEXT (ii),
				IMAGE_INSTANCE_WIDGET_FACE (ii),
				&w, &h, domain);
  /* Adjust the size for borders. */
  if (IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
    *width = w + 4 * widget_instance_border_width (ii);
  if (IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii))
    *height = h + 4 * widget_instance_border_width (ii);
}

/* tree-view geometry - get the height right */
static void
tree_view_query_geometry (Lisp_Object image_instance,
			  int* width, int* height,
			  enum image_instance_geometry UNUSED (disp),
			  Lisp_Object domain)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object items = IMAGE_INSTANCE_WIDGET_ITEMS (ii);


  if (*width)
    {
      /* #### what should this be. reconsider when X has tree views. */
      widget_query_string_geometry (IMAGE_INSTANCE_WIDGET_TEXT (ii),
				    IMAGE_INSTANCE_WIDGET_FACE (ii),
				    width, 0, domain);
    }
  if (*height)
    {
      int len, h;
      /* #### widget face would be better here. */
      default_face_font_info (domain, 0, 0, &h, 0, 0);
      GET_LIST_LENGTH (items, len);
      *height = len * h;
    }
}

/* Get the geometry of a tab control.  This is based on the number of
   items and text therein in the tab control. */
static void
tab_control_query_geometry (Lisp_Object image_instance,
			    int* width, int* height,
			    enum image_instance_geometry UNUSED (disp),
			    Lisp_Object domain)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object items = XCDR (IMAGE_INSTANCE_WIDGET_ITEMS (ii));
  Lisp_Object rest;
  int tw = 0, th = 0;

  LIST_LOOP (rest, items)
    {
      int h, w;

      /* #### Maybe we should allow items to be a list of strings?
	 Ie, autoconvert "label" -> ["label" "label" :selected maybe-t].
	 Maybe there's a better place (or several places) to do this?
	 If so, change image_instantiator_tab_control back to use
	 check_valid_item_list for checking Q_items. -- sjt */
      widget_query_string_geometry (XGUI_ITEM (XCAR (rest))->name,
			     IMAGE_INSTANCE_WIDGET_FACE (ii),
			     &w, &h, domain);
      tw += 5 * widget_instance_border_width (ii); /* some bias */
      tw += w;
      th = max (th, h + 2 * widget_instance_border_width (ii));
    }

  /* Fixup returned values depending on orientation. */
  if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii))
    {
      if (height)	*height = tw;
      if (width)	*width = th;
    }
  else
    {
      if (height)	*height = th;
      if (width)	*width = tw;
    }
}

/* Determine whether only the order has changed for a tab. */
int
tab_control_order_only_changed (Lisp_Object image_instance)
{
  /* Called within redisplay */
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  int found = 0, len, pending_len;
  Lisp_Object rest;

  /* Degenerate case. */
  if (NILP (IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii)))
    return 1;

  /* See whether we just need a change in order. */
  GET_LIST_LENGTH (IMAGE_INSTANCE_WIDGET_ITEMS (ii), len);
  GET_LIST_LENGTH (IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii),
		   pending_len);
  if (len == pending_len)
    {
      LIST_LOOP (rest, XCDR (IMAGE_INSTANCE_WIDGET_ITEMS (ii)))
	{
	  Lisp_Object pending_rest;
	  found = 0;
	  LIST_LOOP (pending_rest,
		     XCDR (IMAGE_INSTANCE_WIDGET_PENDING_ITEMS (ii)))
	    {
	      if (gui_item_equal_sans_selected (XCAR (rest),
						XCAR (pending_rest), 0))
		{
		  found = 1;
		  break;
		}
	    }
	  if (!found)
	    break;
	}
    }
  return found;
}


/*****************************************************************************
 *                              widget layout                               *
 *****************************************************************************/
/* We need to cascade normalization.*/
static Lisp_Object
layout_normalize (Lisp_Object inst, Lisp_Object console_type,
		  Lisp_Object dest_mask)
{
  /* This function can call lisp */
  struct gcpro gcpro1, gcpro2;
  Lisp_Object alist = Qnil, new_items = Qnil, border;
  /* This function can call lisp */
  Lisp_Object items;

  GCPRO2 (alist, new_items);
  alist = tagged_vector_to_alist (inst);
  items = assq_no_quit (Q_items, alist);

  /* We need to normalize sub-objects. */
  if (!NILP (items))
    {
      Lisp_Object rest;
      LIST_LOOP (rest, XCDR (items))
	{
	  /* Substitute the new instantiator */
	  new_items = Fcons (normalize_image_instantiator (XCAR (rest),
							   console_type, dest_mask),
			     new_items);
	}
      new_items = Fnreverse (new_items);
      Fsetcdr (items, new_items);
    }
  /* Normalize the border spec. */
  border = assq_no_quit (Q_border, alist);
  if (!NILP (border) && VECTORP (XCDR (border)))
    {
      Fsetcdr (border, normalize_image_instantiator (XCDR (border),
						     console_type, dest_mask));
    }

  {
    Lisp_Object result = alist_to_tagged_vector (XVECTOR_DATA (inst)[0],
						 alist);
    free_alist (alist);
    RETURN_UNGCPRO (result);
  }
}

/* Update the instances in the layout. */
static void
layout_update (Lisp_Object image_instance, Lisp_Object instantiator)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object items = find_keyword_in_vector (instantiator, Q_items);
  Lisp_Object border_inst = find_keyword_in_vector (instantiator, Q_border);
  Lisp_Object justify = find_keyword_in_vector (instantiator, Q_justify);
  Lisp_Object hjustify = find_keyword_in_vector (instantiator, Q_horizontally_justify);
  Lisp_Object vjustify = find_keyword_in_vector (instantiator, Q_vertically_justify);
  Lisp_Object border = Qnil;
  Lisp_Object children = IMAGE_INSTANCE_LAYOUT_CHILDREN (ii);
  int structure_changed = 0;
  struct gcpro gcpro1;

  /* Pick up horizontal justification, left is the default.*/
  if (!NILP (hjustify)) 
    {
      if (EQ (hjustify, Qright) || EQ (hjustify, Qbottom))
	IMAGE_INSTANCE_SUBWINDOW_H_JUSTIFY (ii) = LAYOUT_JUSTIFY_RIGHT;
      else if (EQ (hjustify, Qcenter))
	IMAGE_INSTANCE_SUBWINDOW_H_JUSTIFY (ii) = LAYOUT_JUSTIFY_CENTER;
    }
  /* If not set use general justification. */
  else if (!NILP (justify))
    {
      if (EQ (justify, Qright) || EQ (justify, Qbottom))
	IMAGE_INSTANCE_SUBWINDOW_H_JUSTIFY (ii) = LAYOUT_JUSTIFY_RIGHT;
      else if (EQ (justify, Qcenter))
	IMAGE_INSTANCE_SUBWINDOW_H_JUSTIFY (ii) = LAYOUT_JUSTIFY_CENTER;
    }

  /* Pick up vertical justification, top is the default. */
  if (!NILP (vjustify)) 
    {
      if (EQ (vjustify, Qright) || EQ (vjustify, Qbottom))
	IMAGE_INSTANCE_SUBWINDOW_V_JUSTIFY (ii) = LAYOUT_JUSTIFY_BOTTOM;
      else if (EQ (vjustify, Qcenter))
	IMAGE_INSTANCE_SUBWINDOW_V_JUSTIFY (ii) = LAYOUT_JUSTIFY_CENTER;
    }
  /* If not set use general justification. */
  else if (!NILP (justify)) 
    {
      if (EQ (justify, Qright) || EQ (justify, Qbottom))
	IMAGE_INSTANCE_SUBWINDOW_V_JUSTIFY (ii) = LAYOUT_JUSTIFY_BOTTOM;
      else if (EQ (justify, Qcenter))
	IMAGE_INSTANCE_SUBWINDOW_V_JUSTIFY (ii) = LAYOUT_JUSTIFY_CENTER;
    }

  /* We want to avoid consing if we can. This is quite awkward because
     we have to deal with the border as well as the items. */
  GCPRO1 (border);

  if (INTP (IMAGE_INSTANCE_LAYOUT_BORDER (ii)))
    {
      border = XCAR (children);
      children = XCDR (children);
    }

#ifdef DEBUG_WIDGET_OUTPUT
  stderr_out ("layout updated\n");
#endif
  /* Update the border. */
  if (!NILP (border_inst))
    {
      if (VECTORP (border_inst))
	{
	  /* We are going to be sneaky here and add the border text as
	     just another child, the layout and output routines don't know
	     this and will just display at the offsets we prescribe. */
	  if (!NILP (border))
	    call3 (Qset_glyph_image, border, border_inst,
		   IMAGE_INSTANCE_DOMAIN (ii));
	  else
	    {
	      border = Fcons (call1 (Qmake_glyph, border_inst), Qnil);
	      structure_changed = 1;
	    }
	  IMAGE_INSTANCE_LAYOUT_BORDER (ii) = make_int (0);
	}
      else
	{
	  if (!NILP (border))
	    {
	      border = Qnil;
	      structure_changed = 1;
	    }
	  if (EQ (border_inst, Qt))
	      IMAGE_INSTANCE_LAYOUT_BORDER (ii) = Qetched_in;
	  else
	    IMAGE_INSTANCE_LAYOUT_BORDER (ii) = border_inst;
	}
    }

  /* Pick up the sub-widgets. */
  if (!NILP (items))
    {
      int len1, len2;
      GET_LIST_LENGTH (items, len1);
      GET_LIST_LENGTH (children, len2);
      /* The structure hasn't changed so just update the images. */
      if (!structure_changed && len1 == len2)
	{
	  /* Pick up the sub-widgets. */
	  for (; !NILP (children); children = XCDR (children), items = XCDR (items))
	    {
	      call3 (Qset_glyph_image, XCAR (children), XCAR (items),
		     IMAGE_INSTANCE_DOMAIN (ii));
	    }
	}
      /* The structure has changed so start over. */
      else
	{
	  /* Instantiate any new glyphs. */
	  for (; !NILP (items); items = XCDR (items))
	    {
	      /* #### We really want to use call_with_suspended_errors
		 here, but it won't allow us to call lisp. */
	      border = Fcons (call1 (Qmake_glyph, XCAR (items)), border);
	    }
	  IMAGE_INSTANCE_LAYOUT_CHILDREN (ii) = Fnreverse (border);
	}
    }
  UNGCPRO;
}

static void
layout_instantiate (Lisp_Object image_instance, Lisp_Object instantiator,
		    Lisp_Object pointer_fg, Lisp_Object pointer_bg,
		    int dest_mask, Lisp_Object domain)
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object orient = find_keyword_in_vector (instantiator, Q_orientation);

#ifdef DEBUG_WIDGET_OUTPUT
  stderr_out ("layout instantiated\n");
#endif
  /* Do widget type instantiation first. */
  widget_instantiate (image_instance, instantiator, pointer_fg, pointer_bg,
		      dest_mask, domain);

  if (NILP (orient))
    {
      IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) = LAYOUT_VERTICAL;
    }

  /* Get child glyphs and finish instantiation. We can't do image
     instance children yet as we might not have a containing
     window. */
  layout_update (image_instance, instantiator);
}

static void
layout_post_instantiate (Lisp_Object UNUSED (image_instance),
			 Lisp_Object UNUSED (instantiator),
			 Lisp_Object UNUSED (domain))
{
}

/* Layout widget. Sizing commentary: we have a number of problems that
   we would like to address. Some consider some of these more
   important than others. It used to be that size information was
   determined at instantiation time and was then fixed forever
   after. Generally this is not what we want. Users want size to be
   "big enough" to accommodate whatever they are trying to show and
   this is dependent on text length, lines, font metrics etc. Of
   course these attributes can change dynamically and so the size
   should changed dynamically also. Only in a few limited cases should
   the size be fixed and remain fixed. Of course this actually means
   that we don't really want to specify the size *at all* for most
   widgets - we want it to be discovered dynamically. Thus we can
   envisage the following scenarios:

   1. A button is sized to accommodate its text, the text changes and the
   button should change size also.

   2. A button is given an explicit size. Its size should never change.

   3. Layout is put inside an area. The size of the area changes, the
   layout should change with it.

   4. A button grows to accommodate additional text. The whitespace
   around it should be modified to cope with the new layout
   requirements.

   5. A button grows. The area surrounding it should grow also if
   possible.

   What metrics are important?
   1. Actual width and height.

   2. Whether the width and height are what the widget actually wants, or
   whether it can grow or shrink.

   Text glyphs are particularly troublesome since their metrics depend
   on the context in which they are being viewed. For instance they
   can appear differently depending on the window face, frame face or
   glyph face. In order to simplify this text glyphs can now only have
   a glyph-face or image-instance face. All other glyphs are
   essentially fixed in appearance. Perhaps the problem is that text
   glyphs are cached on a device basis like most other glyphs. Instead
   they should be cached per-window and then the instance would be
   fixed and we wouldn't have to mess around with font metrics and the
   rest. 

   Another sizing problem is alignment. We provide layout widgets that
   allow users to stack widgets vertically or horizontally. These
   layouts also allow the widgets to be centered (space evenly
   distributed), left or right justified (fixed spacing widgets
   stacked against the left, righ, top or bottom edge). Unfortunately
   this doesn't allow widgets in different layouts to be aligned. For
   instance how should the search dialog be organized for alignment?
   The obvious choice of two vertical columns does not work since the
   size of individual widgets will affect where they get placed. The
   same is true for several rows of widgets. To solve this problem we
   introduce the notion of `logical_unit_height'. This is a size
   quantity that is designed to be big enough to accomodate the
   largest `single height unit'. The function
   widget_logical_unit_height() determines the value of this in
   pixels. It is dependent on the widget face and some combination of
   spacing and border-width. Thus if users specify left or right
   justification in a vertical layout they get something in logical
   units. To simplify this the functions
   `widget-logical-to-character-height' and
   `widget-logical-to-character-width' allow conversion between
   characters and logical units so that frames can be sized
   appropriately. */

/* Query the geometry of a layout widget. */
static void
layout_query_geometry (Lisp_Object image_instance, int* width,
		       int* height, enum image_instance_geometry disp,
		       Lisp_Object UNUSED (domain))
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object items = IMAGE_INSTANCE_LAYOUT_CHILDREN (ii), rest;
  int maxph = 0, maxpw = 0, nitems = 0, ph_adjust = 0;
  int gheight, gwidth, luh;

  /* If we are not initialized then we won't have any children. */
  if (!IMAGE_INSTANCE_INITIALIZED (ii))
      return;

  /* First just set up what we already have. */
  if (width)	*width = IMAGE_INSTANCE_WIDTH (ii);
  if (height)	*height = IMAGE_INSTANCE_HEIGHT (ii);

  /* If we are not allowed to dynamically size then return. */
  if (!IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii)
      &&
      !IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
    return;

  luh = widget_logical_unit_height (ii);

  /* Pick up the border text if we have one. */
  if (INTP (IMAGE_INSTANCE_LAYOUT_BORDER (ii)))
    {
      glyph_query_geometry (XCAR (items), &gwidth, &gheight, disp,
			    image_instance);
      ph_adjust = gheight;
      /* Include text width in vertical layouts. */
      if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_VERTICAL)
	maxpw = gwidth + BORDER_FIDDLE_FACTOR;
      items = XCDR (items);
    }

  /* Flip through the items to work out how much stuff we have to display */
  LIST_LOOP (rest, items)
    {
      Lisp_Object glyph = XCAR (rest);
      glyph_query_geometry (glyph, &gwidth, &gheight, disp, image_instance);

      nitems ++;
      if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_HORIZONTAL)
	{
	  maxph = max (maxph, gheight);
	  maxpw += gwidth;
	}
      else
	{
	  maxpw = max (maxpw, gwidth);
	  maxph += gheight;
	}
    }

  /* Work out minimum space we need to fit all the items. This could
     have been fixed by the user. */
  if (IMAGE_INSTANCE_SUBWINDOW_H_RESIZEP (ii))
    {
      if (!NILP (IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii)))
	{
          Lisp_Object dynamic_width =
	    eval_within_redisplay (IMAGE_INSTANCE_WIDGET_WIDTH_SUBR (ii));
          if (INTP (dynamic_width))
	    *width = XINT (dynamic_width);
	}
      else if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_HORIZONTAL) 
	{
          *width = maxpw + ((nitems + 1) * widget_instance_border_width (ii) +
                            IMAGE_INSTANCE_MARGIN_WIDTH (ii)) * 2;
	}
      else
	{
          *width = maxpw + 2 * (widget_instance_border_width (ii) * 2 +
                                IMAGE_INSTANCE_MARGIN_WIDTH (ii));
	}
  }
 
  /* Work out vertical spacings. */
  if (IMAGE_INSTANCE_SUBWINDOW_V_RESIZEP (ii))
    {
      if (!NILP (IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii)))
	{
          Lisp_Object dynamic_height =
	    eval_within_redisplay (IMAGE_INSTANCE_WIDGET_HEIGHT_SUBR (ii));
          if (INTP (dynamic_height))
	    *height = XINT (dynamic_height);
	}
      else if (IMAGE_INSTANCE_SUBWINDOW_LOGICAL_LAYOUT (ii))
	{
          *height = nitems * luh + ph_adjust;
	}
      else if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_VERTICAL)
	{
          *height = maxph + ((nitems + 1) * widget_instance_border_width (ii) +
                             IMAGE_INSTANCE_MARGIN_WIDTH (ii)) * 2 + ph_adjust;
	}
      else
	{
          *height = maxph + (2 * widget_instance_border_width (ii) +
                             IMAGE_INSTANCE_MARGIN_WIDTH (ii)) * 2 + ph_adjust;
	}
  }
#ifdef DEBUG_WIDGET_OUTPUT
  stderr_out ("layout wants %dx%d\n", *width, *height);
#endif
}

int
layout_layout (Lisp_Object image_instance,
	       int width, int height, int UNUSED (xoffset), int yoffset,
	       Lisp_Object UNUSED (domain))
{
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object rest;
  Lisp_Object items = IMAGE_INSTANCE_LAYOUT_CHILDREN (ii);
  int x, y, maxph = 0, maxpw = 0, nitems = 0,
    horiz_spacing, vert_spacing, ph_adjust = 0;
  int gheight, gwidth;
  /* See comments in widget_logical_unit_height(). */
  int luh = widget_logical_unit_height (ii);

  /* If we are not initialized then we won't have any children. */
  if (!IMAGE_INSTANCE_INITIALIZED (ii))
      return 0;

#ifdef DEBUG_WIDGET_OUTPUT
  stderr_out ("layout output %dx%d\n", width, height);
#endif

  /* Pick up the border text if we have one. A border can have the
     values Qetched_in, Qetched_out, Qbevel_in, Qbevel_out or an
     integer. The first four just affect the display properties of the
     border that is drawn. The last is an offset and implies that the
     first item in the list of subcontrols is a text control that
     should be displayed on the border. */
  if (INTP (IMAGE_INSTANCE_LAYOUT_BORDER (ii)))
    {
      Lisp_Object border = XCAR (items);
      items = XCDR (items);
      glyph_query_geometry (border, &gwidth, &gheight,
			    IMAGE_DESIRED_GEOMETRY, image_instance);
      /* The vertical offset for subsequent items is the full height
	 of the border glyph. */
      ph_adjust = gheight;
      /* The offset for the border is half the glyph height. */
      IMAGE_INSTANCE_LAYOUT_BORDER (ii) = make_int (gheight / 2);

      /* #### Really, what should this be? */
      glyph_do_layout (border, gwidth, gheight, BORDER_FIDDLE_FACTOR, 0,
		       image_instance);
    }

  /* Flip through the items to work out how much stuff we have to display. */
  LIST_LOOP (rest, items)
    {
      Lisp_Object glyph = XCAR (rest);

      glyph_query_geometry (glyph, &gwidth, &gheight,
			    IMAGE_DESIRED_GEOMETRY, image_instance);
      nitems ++;
      if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii)
	  == LAYOUT_HORIZONTAL)
	{
	  maxph = max (maxph, gheight);
	  maxpw += gwidth;
	}
      else
	{
	  maxpw = max (maxpw, gwidth);
	  maxph += gheight;
	}
    }

  /* work out spacing between items and bounds of the layout */
  if (width < maxpw)
    /* The user wants a smaller space than the largest item, so we
       just provide default spacing and will let the output routines
       clip. */
    horiz_spacing = widget_spacing (IMAGE_INSTANCE_DOMAIN (ii));
  else if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii)
	   == LAYOUT_HORIZONTAL) 
    /* We have a larger area to display in so distribute the space
       evenly. */
    horiz_spacing = (width - (maxpw +
			      IMAGE_INSTANCE_MARGIN_WIDTH (ii) * 2))
      / (nitems + 1);
  else
    horiz_spacing = (width - maxpw) / 2
      - IMAGE_INSTANCE_MARGIN_WIDTH (ii);

  /* We are trying here to get widgets to line up when they are left
     or right justified vertically. This means that we must position
     widgets on logical unit boundaries, even though their height may
     be greater or less than a logical unit. In order to avoid
     clipping we need to determine how big the widget wants to be and
     then allocate as many logical units as necessary in order to
     accommodate it. */
  if (height < maxph)
    vert_spacing = widget_spacing (IMAGE_INSTANCE_DOMAIN (ii)) * 2;
  else if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii)
	   == LAYOUT_VERTICAL)
    {
      if (!IMAGE_INSTANCE_SUBWINDOW_V_CENTERED (ii))
	vert_spacing = widget_spacing (IMAGE_INSTANCE_DOMAIN (ii)) * 2;
      else
	vert_spacing = (height - (maxph + ph_adjust +
				  IMAGE_INSTANCE_MARGIN_WIDTH (ii) * 2))
	  / (nitems + 1);
    }
  else
    vert_spacing = (height - (maxph + ph_adjust)) / 2
      - IMAGE_INSTANCE_MARGIN_WIDTH (ii);

  y = yoffset = vert_spacing + ph_adjust + IMAGE_INSTANCE_MARGIN_WIDTH (ii);
  x = horiz_spacing + IMAGE_INSTANCE_MARGIN_WIDTH (ii);

  /* Now flip through putting items where we want them, paying
     attention to justification. Make sure we don't mess with the
     border glyph. */
  LIST_LOOP (rest, items)
    {
      Lisp_Object glyph = XCAR (rest);

      glyph_query_geometry (glyph, &gwidth, &gheight,
			    IMAGE_DESIRED_GEOMETRY, image_instance);

      if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_HORIZONTAL)
	{
	  if (IMAGE_INSTANCE_SUBWINDOW_BOTTOM_JUSTIFIED (ii))
	    y = height - (gheight + vert_spacing);
	  else if (IMAGE_INSTANCE_SUBWINDOW_V_CENTERED (ii))
	    y = (height - gheight) / 2;
	}
      else
	{
	  if (IMAGE_INSTANCE_SUBWINDOW_RIGHT_JUSTIFIED (ii))
	    x = width - (gwidth + horiz_spacing);
	  else if (IMAGE_INSTANCE_SUBWINDOW_H_CENTERED (ii))
	    x = (width - gwidth) / 2;
	}

      /* Now layout subwidgets if they require it. */
      glyph_do_layout (glyph, gwidth, gheight, x, y, image_instance);

      if (IMAGE_INSTANCE_SUBWINDOW_ORIENT (ii) == LAYOUT_HORIZONTAL)
	{
	  x += (gwidth + horiz_spacing);
	}
      else
	{
	  y += (gheight + vert_spacing);
	  if (!IMAGE_INSTANCE_SUBWINDOW_V_CENTERED (ii))
	    {
	      /* justified, vertical layout, try and align on logical unit
		 boundaries. */
	      y = ROUND_UP (y - yoffset, luh) + yoffset;
	    }
	}

    }
  return 1;
}

/* Get the glyphs that comprise a layout. These are created internally
   and so are otherwise inaccessible to lisp. We need some way of getting
   properties from the widgets that comprise a layout and this is the
   simplest way of doing it.

   #### Eventually we should allow some more intelligent access to
   sub-widgets. */
static Lisp_Object
layout_property (Lisp_Object image_instance, Lisp_Object prop)
{
  /* This function can GC. */
  Lisp_Image_Instance *ii = XIMAGE_INSTANCE (image_instance);
  if (EQ (prop, Q_items))
    {
      if (INTP (IMAGE_INSTANCE_LAYOUT_BORDER (ii)) &&
	  CONSP (IMAGE_INSTANCE_LAYOUT_CHILDREN (ii)))
	return Fcopy_sequence (XCDR
			       (IMAGE_INSTANCE_LAYOUT_CHILDREN (ii)));
      else
	return Fcopy_sequence (IMAGE_INSTANCE_LAYOUT_CHILDREN (ii));
    }
  return Qunbound;
}

/* Layout subwindows if they are real subwindows. */
static int
native_layout_layout (Lisp_Object image_instance,
		      int width, int height, int xoffset, int yoffset,
		      Lisp_Object domain)
{
  Lisp_Image_Instance* ii = XIMAGE_INSTANCE (image_instance);
  Lisp_Object rest;

  /* The first time this gets called, the layout will be only
     partially instantiated. The children get done in
     post_instantiate. */
  if (!IMAGE_INSTANCE_INITIALIZED (ii))
    return 0;

  /* Defining this overrides the default layout_layout so we first have to call that to get
     suitable instances and values set up. */
  layout_layout (image_instance, width, height, xoffset, yoffset, domain);

  LIST_LOOP (rest, IMAGE_INSTANCE_LAYOUT_CHILDREN (ii))
    {
      struct display_glyph_area dga;
      dga.xoffset = 0;
      dga.yoffset = 0;
      dga.width = IMAGE_INSTANCE_WIDTH (ii);
      dga.height = IMAGE_INSTANCE_HEIGHT (ii);

      map_subwindow (XCAR (rest),
		     IMAGE_INSTANCE_XOFFSET (ii),
		     IMAGE_INSTANCE_YOFFSET (ii), &dga);
    }
  return 1;
}

DEFUN ("widget-logical-to-character-width", Fwidget_logical_to_character_width, 1, 3, 0, /*
Convert the width in logical widget units to characters.
Logical widget units do not take into account adjusments made for
layout borders, so this adjusment is approximated.
*/
       (width, UNUSED (face), domain))
{
  int w, neww, charwidth;
  int border_width = DEFAULT_WIDGET_BORDER_WIDTH;

  if (NILP (domain))
    domain = Fselected_frame (Qnil);

  CHECK_INT (width);
  w = XINT (width);
  
  if (HAS_DEVMETH_P (DOMAIN_XDEVICE (domain), widget_border_width))
    border_width = DEVMETH (DOMAIN_XDEVICE (domain), widget_border_width, ());

  default_face_font_info (domain, 0, 0, 0, &charwidth, 0);
  neww = ROUND_UP (charwidth * w + 4 * border_width + 2 * widget_spacing (domain), 
		charwidth) / charwidth;
  
  return make_int (neww);
}

DEFUN ("widget-logical-to-character-height", Fwidget_logical_to_character_height, 1, 3, 0, /*
Convert the height in logical widget units to characters.
Logical widget units do not take into account adjusments made for
layout borders, so this adjustment is approximated.

If the components of a widget layout are justified to the top or the
bottom then they are aligned in terms of `logical units'. This is a
size quantity that is designed to be big enough to accomodate the
largest `single height' widget. It is dependent on the widget face and
some combination of spacing and border-width. Thus if you specify top
or bottom justification in a vertical layout the subcontrols are laid
out one per logical unit. This allows adjoining layouts to have
identical alignment for their subcontrols.

Since frame sizes are measured in characters, this function allows you
to do appropriate conversion between logical units and characters.
*/
       (height, UNUSED (face), domain))
{
  int h, newh, charheight;
  
  CHECK_INT (height);
  if (NILP (domain))
    domain = Fselected_frame (Qnil);

  h = XINT (height);

  default_face_font_info (domain, 0, 0, &charheight, 0, 0);
  newh = ROUND_UP (logical_unit_height (Fsymbol_name (Qwidget), 
					Vwidget_face, domain) * h, charheight)
    / charheight;

  return make_int (newh);
}


/************************************************************************/
/*                            initialization                            */
/************************************************************************/

void
syms_of_glyphs_widget (void)
{
  DEFSYMBOL (Qetched_in);
  DEFSYMBOL (Qetched_out);
  DEFSYMBOL (Qbevel_in);
  DEFSYMBOL (Qbevel_out);
  DEFSYMBOL (Qmake_glyph);

  DEFSUBR (Fwidget_logical_to_character_height);
  DEFSUBR (Fwidget_logical_to_character_width);
}

#define VALID_GUI_KEYWORDS(type) do {					      \
  IIFORMAT_VALID_NONCOPY_KEYWORD (type, Q_active, check_valid_anything);      \
  IIFORMAT_VALID_KEYWORD (type, Q_suffix, check_valid_anything);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_keys, check_valid_string);		      \
  IIFORMAT_VALID_KEYWORD (type, Q_style, check_valid_symbol);		      \
  IIFORMAT_VALID_NONCOPY_KEYWORD (type, Q_selected, check_valid_anything);    \
  IIFORMAT_VALID_KEYWORD (type, Q_filter, check_valid_anything);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_config, check_valid_symbol);		      \
  IIFORMAT_VALID_KEYWORD (type, Q_included, check_valid_anything);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_initial_focus, check_valid_anything);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_key_sequence, check_valid_string);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_accelerator, check_valid_string);	      \
  IIFORMAT_VALID_KEYWORD (type, Q_label, check_valid_anything);		      \
  IIFORMAT_VALID_NONCOPY_KEYWORD (type, Q_callback, check_valid_callback);    \
  IIFORMAT_VALID_NONCOPY_KEYWORD (type, Q_callback_ex, check_valid_callback); \
  IIFORMAT_VALID_NONCOPY_KEYWORD (type, Q_descriptor,			      \
				  check_valid_string_or_vector);	      \
} while (0)

#define VALID_WIDGET_KEYWORDS(type) do {				      \
  IIFORMAT_VALID_KEYWORD (type, Q_width, check_valid_int);		      \
  IIFORMAT_VALID_KEYWORD (type, Q_height, check_valid_int);		      \
  IIFORMAT_VALID_KEYWORD (type, Q_pixel_width, check_valid_int_or_function);  \
  IIFORMAT_VALID_KEYWORD (type, Q_pixel_height, check_valid_int_or_function); \
  IIFORMAT_VALID_KEYWORD (type, Q_face, check_valid_face);		      \
} while (0)


static void image_instantiator_widget (void)
{ /* we only do this for properties */
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT_NO_SYM (widget, "widget");
  IIFORMAT_HAS_METHOD (widget, property);
  IIFORMAT_HAS_METHOD (widget, update);
  IIFORMAT_HAS_METHOD (widget, query_geometry);
  IIFORMAT_HAS_METHOD (widget, layout);
}

static void image_instantiator_buttons (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (button, "button");
  IIFORMAT_HAS_SHARED_METHOD (button, validate, widget);
  IIFORMAT_HAS_SHARED_METHOD (button, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (button, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (button, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (button, normalize, widget);
  IIFORMAT_HAS_SHARED_METHOD (button, governing_domain, subwindow);
  IIFORMAT_HAS_METHOD (button, query_geometry);
  IIFORMAT_VALID_KEYWORD (button,
			  Q_image, check_valid_instantiator);
  VALID_WIDGET_KEYWORDS (button);
  VALID_GUI_KEYWORDS (button);
}

static void image_instantiator_edit_fields (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (edit_field, "edit-field");
  IIFORMAT_HAS_SHARED_METHOD (edit_field, validate, widget);
  IIFORMAT_HAS_SHARED_METHOD (edit_field, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (edit_field, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (edit_field, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (edit_field, governing_domain, subwindow);
  IIFORMAT_HAS_METHOD (edit_field, query_geometry);
  VALID_WIDGET_KEYWORDS (edit_field);
  VALID_GUI_KEYWORDS (edit_field);
}

static void image_instantiator_combo_box (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (combo_box, "combo-box");
  IIFORMAT_HAS_METHOD (combo_box, validate);
  IIFORMAT_HAS_SHARED_METHOD (combo_box, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (combo_box, governing_domain, subwindow);

  VALID_GUI_KEYWORDS (combo_box);

  IIFORMAT_VALID_KEYWORD (combo_box, Q_width, check_valid_int);
  IIFORMAT_VALID_KEYWORD (combo_box, Q_height, check_valid_int);
  IIFORMAT_VALID_KEYWORD (combo_box, Q_pixel_width,
			  check_valid_int_or_function);
  IIFORMAT_VALID_KEYWORD (combo_box, Q_face, check_valid_face);
  IIFORMAT_VALID_KEYWORD (combo_box, Q_items, check_valid_item_list);
}

static void image_instantiator_scrollbar (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (scrollbar, "scrollbar");
  IIFORMAT_HAS_SHARED_METHOD (scrollbar, validate, widget);
  IIFORMAT_HAS_SHARED_METHOD (scrollbar, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (scrollbar, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (scrollbar, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (scrollbar, governing_domain, subwindow);
  VALID_GUI_KEYWORDS (scrollbar);

  IIFORMAT_VALID_KEYWORD (scrollbar, Q_pixel_width,
			  check_valid_int_or_function);
  IIFORMAT_VALID_KEYWORD (scrollbar, Q_pixel_height,
			  check_valid_int_or_function);
  IIFORMAT_VALID_KEYWORD (scrollbar, Q_face, check_valid_face);
}

static void image_instantiator_progress_guage (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (progress_gauge, "progress-gauge");
  IIFORMAT_HAS_SHARED_METHOD (progress_gauge, validate, widget);
  IIFORMAT_HAS_SHARED_METHOD (progress_gauge, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (progress_gauge, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (progress_gauge, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (progress_gauge, governing_domain, subwindow);
  VALID_WIDGET_KEYWORDS (progress_gauge);
  VALID_GUI_KEYWORDS (progress_gauge);

  IIFORMAT_VALID_KEYWORD (progress_gauge, Q_value, check_valid_int);
}

static void image_instantiator_tree_view (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (tree_view, "tree-view");
  IIFORMAT_HAS_SHARED_METHOD (tree_view, validate, combo_box);
  IIFORMAT_HAS_SHARED_METHOD (tree_view, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (tree_view, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (tree_view, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (tree_view, governing_domain, subwindow);
  IIFORMAT_HAS_METHOD (tree_view, query_geometry);
  VALID_WIDGET_KEYWORDS (tree_view);
  VALID_GUI_KEYWORDS (tree_view);
  IIFORMAT_VALID_KEYWORD (tree_view, Q_items, check_valid_item_list);
}

static void image_instantiator_tab_control (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (tab_control, "tab-control");
  IIFORMAT_HAS_SHARED_METHOD (tab_control, validate, combo_box);
  IIFORMAT_HAS_SHARED_METHOD (tab_control, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (tab_control, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (tab_control, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (tab_control, governing_domain, subwindow);
  IIFORMAT_HAS_METHOD (tab_control, query_geometry);
  VALID_WIDGET_KEYWORDS (tab_control);
  VALID_GUI_KEYWORDS (tab_control);
  IIFORMAT_VALID_KEYWORD (tab_control, Q_orientation,
			  check_valid_tab_orientation);
  IIFORMAT_VALID_KEYWORD (tab_control, Q_items, check_valid_item_list);
}

static void image_instantiator_labels (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (label, "label");
  IIFORMAT_HAS_SHARED_METHOD (label, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (label, instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (label, post_instantiate, widget);
  IIFORMAT_HAS_SHARED_METHOD (label, governing_domain, subwindow);
  VALID_WIDGET_KEYWORDS (label);
  IIFORMAT_VALID_KEYWORD (label, Q_descriptor, check_valid_string);
}

#define VALID_LAYOUT_KEYWORDS(layout)					   \
  VALID_WIDGET_KEYWORDS (layout);					   \
  IIFORMAT_VALID_KEYWORD (layout, Q_orientation, check_valid_orientation); \
  IIFORMAT_VALID_KEYWORD (layout, Q_justify, check_valid_justification);   \
  IIFORMAT_VALID_KEYWORD (layout, Q_vertically_justify, check_valid_justification);   \
  IIFORMAT_VALID_KEYWORD (layout, Q_horizontally_justify, check_valid_justification);   \
  IIFORMAT_VALID_KEYWORD (layout, Q_border, check_valid_border);	   \
  IIFORMAT_VALID_KEYWORD (layout, Q_margin_width, check_valid_int);	   \
  IIFORMAT_VALID_KEYWORD (layout, Q_items,				   \
			  check_valid_instantiator_list)

static void image_instantiator_layout (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (layout, "layout");
  IIFORMAT_HAS_SHARED_METHOD (layout, possible_dest_types, widget);
  IIFORMAT_HAS_METHOD (layout, instantiate);
  IIFORMAT_HAS_METHOD (layout, post_instantiate);
  IIFORMAT_HAS_SHARED_METHOD (layout, governing_domain, subwindow);
  IIFORMAT_HAS_METHOD (layout, normalize);
  IIFORMAT_HAS_METHOD (layout, query_geometry);
  IIFORMAT_HAS_METHOD (layout, layout);
  IIFORMAT_HAS_METHOD (layout, update);
  IIFORMAT_HAS_METHOD (layout, property);

  VALID_GUI_KEYWORDS (layout);
  VALID_LAYOUT_KEYWORDS (layout);
}

static void image_instantiator_native_layout (void)
{
  INITIALIZE_IMAGE_INSTANTIATOR_FORMAT (native_layout, "native-layout");
  IIFORMAT_HAS_SHARED_METHOD (native_layout, possible_dest_types, widget);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, instantiate, layout);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, post_instantiate, layout);
  IIFORMAT_HAS_METHOD (native_layout, layout);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, governing_domain, subwindow);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, normalize, layout);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, query_geometry, layout);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, layout, layout);
  IIFORMAT_HAS_SHARED_METHOD (native_layout, property, layout);

  VALID_GUI_KEYWORDS (native_layout);
  VALID_LAYOUT_KEYWORDS (native_layout);
}

void
image_instantiator_format_create_glyphs_widget (void)
{
  image_instantiator_widget();
  image_instantiator_buttons();
  image_instantiator_edit_fields();
  image_instantiator_combo_box();
  image_instantiator_scrollbar();
  image_instantiator_progress_guage();
  image_instantiator_tree_view();
  image_instantiator_tab_control();
  image_instantiator_labels();
  image_instantiator_layout();
  image_instantiator_native_layout();
}

void
reinit_vars_of_glyphs_widget (void)
{
#ifdef DEBUG_WIDGETS
  debug_widget_instances = 0;
#endif
}

void
vars_of_glyphs_widget (void)
{
}


void
specifier_vars_of_glyphs_widget (void)
{
  DEFVAR_SPECIFIER ("widget-border-width",
		    &Vwidget_border_width /*
*Border width of widgets.
This is a specifier; use `set-specifier' to change it.
*/ );
  Vwidget_border_width = Fmake_specifier (Qnatnum);
}