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[Emacs-diffs] xwidget cf51c3f: replaced docs with external link


From: Joakim Verona
Subject: [Emacs-diffs] xwidget cf51c3f: replaced docs with external link
Date: Tue, 30 Dec 2014 15:20:58 +0000

branch: xwidget
commit cf51c3f0647d317a8b577dda011598a037ccac2f
Author: jave <address@hidden>
Commit: jave <address@hidden>

    replaced docs with external link
---
 README.xwidget | 1730 +-------------------------------------------------------
 1 files changed, 1 insertions(+), 1729 deletions(-)

diff --git a/README.xwidget b/README.xwidget
index ff060bf..cfde411 100644
--- a/README.xwidget
+++ b/README.xwidget
@@ -1,1730 +1,2 @@
 -*-org-*-
-* Xwidgets
-
-This is an experimental branch to enable embedding of GTK widgets
-inside an Emacs window. The Emacs abstraction is called an Xwidget,
-for eXternal widget, and also in reference to the Xembed protocoll.
-
-There is a demo file called xwidget-test.el which shows some of the
-possibilities. There are some screnshots at the emacswiki.
-
-Currently its possible to insert buttons, sliders, xembed widgets, and
-webkit in the buffer. It works similar to the support for images in
-Emacs.  Adding more types of widgets should be fairly straightforward,
-but will require adapter code for each type.
-
-A difference from images is that xwidgets live their own life. You
-create them with an api, get a reference, and tie them to a particular
-buffer with a display spec. 
-
-Each xwidget can have several views. In MVC terms, an xwidget is the
-model, and an xwidget-view is a view of the xwidget in a particular
-Emacs window.
-
-The xwidget code attempts to keep the visual appearance of the views
-in sync with through an Observer pattern implementation. This is
-necessary to support the Emacs window paradigm.
-
-** building
-bzr co bzr+ssh://bzr.savannah.gnu.org/emacs/xwidget/
-#or:
-#git clone https://github.com/jave/xwidget-emacs.git
-#the below compiler flags shouldn't be strictly necessary
-export CFLAGS=" -g"
-./configure --with-xwidgets --enable-asserts --with-x-toolkit=gtk3
-make -j4
-gdb -ex run src/emacs
-
-** try it out
-If you have GTK3 and gtk-webkit installed, you should be able to
-start the embedded webkit browser now:
-
-M-X xwidget-webkit-browse-url
-
-If that didnt work out try the minimal demonstration instead:
-
-(load-library "xwidget-test")
-(xwidget-demo-a-button)
-
-It looks unimpressive, but it's a gtk button inside an Emacs buffer!
-*** webkit hints
-If you got webkit working, great! Please note, though, that the
-current support is far from a full fledged browser. My focus is on
-delivering a component that can be used to build a full emacs based
-browser on. Since I implement a browse-url function you can get quite
-far just by:
-
-(setq browse-url-browser-function 'xwidget-webkit-browse-url)
-
-then all Emacs browser interface systems work to a degree.
-heres stuff I use currenly
-
-- m-x anything-surfraw interfaces to search engines
-- C-o in org mode opens links inside org
-- m-x ffap opens links anywhere in a buffer
-- m-x gtk-lookup-symbol searches gtk docs
-- m-x bookmark-jump
-etc..
-
-I'll add more examples as I go along.
-
-However theres lots of support missing, see TODO list for
-information. Briefly:
-- download handling
-- keyboard field navigation
-- isearch
-- history
-- sites that use flash. I dont really care about this issue so its
-unlikely to be fixed. Just a heads up.
-
-** Stability
-Beginning with Summer 2011 I am now able to use Xwidget Emacs as my
-primary Emacs. That is good for the project and the stability of the
-code.
-
-At the time of writing I have 24 hour Emacs uptime with several
-embedded webkit browsers, Gnus, org-mode, tramp, etc. etc.
-
-That said, there are still many improvements that needs to be done,
-particularily in memory management. Expect xwidget emacs to leak
-heavily for now.
-
-** timeline for inclusion in trunk
-The Emacs 24 feature freeze is passed, so xwidgets won't probably be merged
-until Emacs 25. OTOH since I now use xwidget emacs as my primary
-emacs, I will merge from trunk much more often than in the past.
-
-** reporting bugs
-Emacs xwidgets uses the same tracker as mainline emacs, but a
-different package. To report a bug:
-M-x report-xwidget-bug
-
-
-browse bugs:
-http://debbugs.gnu.org/cgi/pkgreport.cgi?package=emacs-xwidgets
-** Thanks
address@hidden There are very helpful people there. When I
-started the xwidget project I had no clue about the Emacs internals. 
-
-* Brief overview of how xwidgets work
-Xwidgets work in one way like images in Emacs. You bind a display spec very
-similar to an image display spec to buffer contents. The display engine will
-notice the display spec and try to display the xwidget there. The display 
engine
-prepares space at the right place for the xwidget and so on for free, as long 
as
-we provide proper sizes and so on back to the redisplay engine.
-
-** Issues
-The problem is that Emacs cant actually draw the widgets, as it can with
-images. Emacs must notify GTK about where the widgets should be, and how they
-should be clipped and so on, and this information must be given to GTK
-synchronous with Emacs display changes. Ok, so why is that difficult then?
-
-- How do we know when a widget is NOT to be drawn? The only way I found so far
-  is having a flag for each xwdiget, that is reset before a redisplay. When an
-  xwidget is encountered during display, the flag is set. After redisplay,
-  iterate all xwidgets and hide those which hasnt been displayed. 
-
-- The gtk socket type for embedding external applications is desirable
-  but presents a lot of difficulties of its own. One difficulty is
-  deciding which input events to forward, and when and how to do it.
-
-** placement and clipping
-the entire emacs frame is a gtk window. we use the fixed layout
-manager to place xwidgets on the frame. coordinates are supplied by
-the emacs display engine. widgets are placed inside an intermediate
-window, called the widgetwindow. the widgetwindows are placed on the
-emacs frame.
-
-this way was chosen to simplify clipping of the widgets against emacs
-window borders.
-
-
-** different strategies
-Integrating toolkit widgets(gtk in this case) and the emacs display
-engine is more difficult than your plain average gui application, and
-different strategies has been tested and will continue to be tested.
-
-There was a distinction between live xwidgets and
-phantom xwidgets, previous to the change to MVC.
-
-- the first aproach was to have the live xwidget on-screen, and move
-  them about. the phantoms were generated by snapshoting the live
-  xwidget. 
-
-the drawback of that aproach was that the gtk toolkit is admirably
-lazy and doesnt draw the widget if its not actualy shown, meaning that
-the snapshots for the phantoms will show garbage.
-
-- the second aproach was to use composition support. that tells gtk
-  that the widget should be drawn in an off-screen buffer and drawn on
-  screen by the application.
-
-this has the primary advantage that the snapshot is always
-available, and enables the possibility of more eye-candy like drawing
-live and phantom widgets in different colors.
-
-the drawback is that its our own responsibility to handle drawing,
-which puts more of the display optimization burden on us.
-
-this is aproach worked so-so.
-
-- another aproach is to have both live and phantom widgets drawn
-  on-screen by proxy gtk objects. the live xwidget will be entirely
-  handled in an off-screen window, and the proxy objects will redirect
-  events there.
-
-- combine on-screen and off-screen aproaches. maybe composition is the
-  way to go for most cases, but on-screen xembeding is the way to go
-  for particular special cases, like showing video in a
-  window. off-screen rendering and whatnot, is not efficient in that
-  particular case, and the user will simply have to accept that the
-  phantom of a video widget isnt particularily beautiful.
-
-- The current and seemingly sanest aproach implements a MVC pattern.
-
-** Testing
-;;test like:
-;; cd /path/to/xwidgets-emacs-dir
-;; make   all&&  src/emacs -q --eval "(progn (load 
\"`pwd`/lisp/xwidget-test.el\") (xwidget-demo-basic))"
-
-** MVC and Xembedd
-The MVC approach appears to be at least in principle robust for plain gtk
-widgets. For the interesting case of gtk sockets which implements an
-xembed host widget that allows for embedding other applications inside
-an Emacs window, the story gets more complex.
-
-The problem is that xembed is designed to plug an application window
-inside a socket and thats it. You can't move a plug between
-sockets. I tried numerous hacks to get around this but there is
-nothing that works really well.
-
-Therefore the Emacs part of the code will only expose well-defined
-interfaces. cooperating applications will be able to use the interface
-in a well defined manner. The problem is that there is no known xembeddable
-application that implement the needed type of functionality, which is
-allowing for creating new windows on the fly that plug into new
-sockets.
-
-Therefore I will attempt to provide an external application that wraps
-another application and through hacks attempts to provide the needed
-multi view xembed function. That way Emacs is sane and the insanity
-contained.
-
-This app will work by providing a socket that an app plugs into. The
-socket window is copied efficiently by means of composition to a
-number of other windows, that are then plugged into the different
-Emacs sockets. 
-** old notes from x_draw_xwidget_glyph_string
-
-    BUG it seems this method for some reason is called with bad s->x and s->y 
sometimes.
-    When this happens the xwidget doesnt move on screen as it should.
-    This might be because of x_scroll_run. Emacs decides to scroll the screen 
by blitting sometimes.
-    then emacs doesnt try to actualy call the paint routines, which means this 
here code will never
-    run so the xwidget wont know it has been moved.
-
-    Solved temporarily by never optimizing in 
try_window_reusing_current_matrix().
-
-    BUG the phantoming code doesnt work very well when the live xwidget is off 
screen.
-    you will get weirdo display artefacts. Composition ought to solve this, 
since that means the live window is
-    always available in an off-screen buffer. My current attempt at 
composition doesnt work properly however.
-
-    //allocation debugging. the correct values cant be expected to show upp 
immediately, but eventually they should get to be ok
-    // this is because we dont know when the container gets around to do layout
-    //GtkAllocation galloc;
-    //gtk_widget_get_allocation(GTK_WIDGET (xv->widgetwindow), &galloc);
-    //printf("allocation %d %d , %d %d\n", 
galloc.x,galloc.y,galloc.width,galloc.height);
-
-
-*** old notes about the old live/phantom scheme
-
-   //TODO:
-   // 1) always draw live xwidget in selected window
-   // (2) if there were no live instances of the xwidget in selected window, 
also draw it live)
-   // 3) if there was a live xwidget previously, now phantom it.
-
-   else
-     {
-       //ok, we are painting the xwidgets in non-selected window, so draw a 
phantom
-       //printf("draw phantom xwidget at:%d %d\n",x,y);
-       //xwidget_composite_draw_phantom (xw, x, y, clipx, clipy); //TODO MVC 
there will be very few cases of phantoming
-     }
-
-
-   atm this works as follows: only check if xwidgets are displayed in the
-   "selected window". if not, hide them or phantom them.
-
-   this means valid cases like xwidgets being displayed only once in
-   non-selected windows, does not work well. they should also be visible
-   in that case not phantomed.
-
-* ToDo:s
-** TODO webkit crash
-[2013-04-13 Sat] seems to crash a lot on http://www.dilbert.com
-Not always, but enough to be annoying.
-
-** TODO optimize drawing off large offscreen widgets
-Currently I just allocate as large an area as the offscreen webkit
-widget desires. This works well most of the time. But a HTML page
-might in principle be of infinite height so there are cases where this
-doesn't work too well.
-
-Heres a proposed strategy:
-- never grow the offscreen webkit over xwidget-webkit-max-height
-- allow for webkit to handle its own scrolling internally as well
-- be more clever about when you have more than one emacs window
-  showing the same webkit instance. 
-- allow to grow the offscreen instance in steps rather than just
-  allocate the entire height at once
-
-** DONE again a trace
-   CLOSED: [2011-10-28 Fri 13:48]
-[2011-08-23 Tue]
-the hunch is that since I still hand-wave the view storage the array
-can get out of synchronous. so maybe switching to a lisp structure
-will help as it did for the model. Anyway, doesnt happen at all often.
-*** the trace
-(gdb) bt
-#0  0x0000000000685304 in xwidget_touch (xv=0x0) at xwidget.c:1225
-#1  0x00000000006853e7 in xwidget_end_redisplay (w=0x11b42ca0, matrix=
-    0xff9bf40) at xwidget.c:1272
-#2  0x000000000041cc31 in update_window (w=0x11b42ca0, force_p=0)
-    at dispnew.c:3705
-#3  0x000000000041c0e5 in update_window_tree (w=0x11b42ca0, force_p=0)
-    at dispnew.c:3331
-#4  0x000000000041be8b in update_frame (f=0x1682a50, force_p=0, 
-    inhibit_hairy_id_p=0) at dispnew.c:3258
-#5  0x000000000045066f in redisplay_internal () at xdisp.c:12931
-#6  0x000000000044e210 in redisplay () at xdisp.c:12110
-#7  0x0000000000567e65 in read_char (commandflag=1, nmaps=7, maps=
-    0x7fffffffc040, prev_event=12708226, used_mouse_menu=0x7fffffffc254, 
-    end_time=0x0) at keyboard.c:2447
-#8  0x000000000057613c in read_key_sequence (keybuf=0x7fffffffc4a0, bufsize=
-    30, prompt=12708226, dont_downcase_last=0, can_return_switch_frame=1, 
-    fix_current_buffer=1) at keyboard.c:9299
-#9  0x0000000000565d45 in command_loop_1 () at keyboard.c:1448
-#10 0x0000000000601008 in internal_condition_case (bfun=
-    0x565962 <command_loop_1>, handlers=12760466, hfun=0x565259 <cmd_error>)
-    at eval.c:1490
-#11 0x0000000000565659 in command_loop_2 (ignore=12708226) at keyboard.c:1159
-#12 0x0000000000600992 in internal_catch (tag=12873826, func=
----Type <return> to continue, or q <return> to quit---
-    0x565633 <command_loop_2>, arg=12708226) at eval.c:1247
-#13 0x00000000005655bd in command_loop () at keyboard.c:1124
-#14 0x0000000000564da7 in recursive_edit_1 () at keyboard.c:759
-#15 0x0000000000564f43 in Frecursive_edit () at keyboard.c:823
-#16 0x000000000060444f in Ffuncall (nargs=1, args=0x7fffffffca20)
-    at eval.c:2986
-#17 0x00000000006507f8 in exec_byte_code (bytestr=145172929, vector=145179445, 
-    maxdepth=116, args_template=12708226, nargs=0, args=0x0) at bytecode.c:785
-#18 0x0000000000604eec in funcall_lambda (fun=140575909, nargs=2, arg_vector=
-    0x7fffffffcfe8) at eval.c:3220
-#19 0x000000000060467e in Ffuncall (nargs=3, args=0x7fffffffcfe0)
-    at eval.c:3038
-#20 0x00000000006035fc in Fapply (nargs=2, args=0x7fffffffd0b0) at eval.c:2494
-#21 0x0000000000603b43 in apply1 (fn=12874242, arg=301666310) at eval.c:2732
-#22 0x00000000005feb25 in call_debugger (arg=301666310) at eval.c:220
-#23 0x0000000000601ca9 in maybe_call_debugger (conditions=9431542, sig=
-    12761282, data=301666742) at eval.c:1893
-#24 0x0000000000601785 in Fsignal (error_symbol=12761282, data=301666742)
-    at eval.c:1714
-#25 0x0000000000601898 in xsignal (error_symbol=12761282, data=301666742)
-    at eval.c:1749
-#26 0x0000000000601926 in xsignal2 (error_symbol=12761282, arg1=102756373, 
-    arg2=0) at eval.c:1770
----Type <return> to continue, or q <return> to quit---
-#27 0x0000000000604d6e in funcall_lambda (fun=102756373, nargs=0, arg_vector=
-    0x7fffffffd398) at eval.c:3189
-#28 0x000000000060467e in Ffuncall (nargs=1, args=0x7fffffffd390)
-    at eval.c:3038
-#29 0x00000000006507f8 in exec_byte_code (bytestr=54783137, vector=109656229, 
-    maxdepth=12, args_template=12708226, nargs=0, args=0x0) at bytecode.c:785
-#30 0x0000000000604eec in funcall_lambda (fun=109656517, nargs=0, arg_vector=
-    0x7fffffffd890) at eval.c:3220
-#31 0x000000000060467e in Ffuncall (nargs=1, args=0x7fffffffd888)
-    at eval.c:3038
-#32 0x0000000000603b08 in apply1 (fn=109656517, arg=12708226) at eval.c:2725
-#33 0x00000000005fc8c9 in Fcall_interactively (function=109656517, record_flag=
-    12708226, keys=12754549) at callint.c:379
-#34 0x00000000006044c2 in Ffuncall (nargs=4, args=0x7fffffffdc60)
-    at eval.c:2996
-#35 0x0000000000603c57 in call3 (fn=12893554, arg1=109656517, arg2=12708226, 
-    arg3=12708226) at eval.c:2789
-#36 0x00000000005784cd in Fcommand_execute (cmd=109656517, record_flag=
-    12708226, keys=12708226, special=12708226) at keyboard.c:10290
-#37 0x00000000005661fb in command_loop_1 () at keyboard.c:1575
-#38 0x0000000000601008 in internal_condition_case (bfun=
-    0x565962 <command_loop_1>, handlers=12760466, hfun=0x565259 <cmd_error>)
-    at eval.c:1490
----Type <return> to continue, or q <return> to quit---
-#39 0x0000000000565659 in command_loop_2 (ignore=12708226) at keyboard.c:1159
-#40 0x0000000000600992 in internal_catch (tag=12756258, func=
-    0x565633 <command_loop_2>, arg=12708226) at eval.c:1247
-#41 0x000000000056560c in command_loop () at keyboard.c:1138
-#42 0x0000000000564da7 in recursive_edit_1 () at keyboard.c:759
-#43 0x0000000000564f43 in Frecursive_edit () at keyboard.c:823
-#44 0x0000000000563052 in main (argc=1, argv=0x7fffffffe678) at emacs.c:1711
-
-Lisp Backtrace:
-"recursive-edit" (0xffffca28)
-"debug" (0xffffcfe8)
-"image-bol" (0xffffd398)
-0x68939c0 PVEC_COMPILED
-"call-interactively" (0xffffdc68)
-(gdb) 
-
-
-** DONE new annoying trace
-   CLOSED: [2011-08-13 Sat 16:16]
-maybe related to scroll inhibiting or cursor inhibiting code.
-It appears actually to be related to GLYPH_DEBUG=1. this flag is no
-longer needed.
-*** the trace
-Breakpoint 1, abort () at emacs.c:383
-383       kill (getpid (), SIGABRT);
-Missing separate debuginfos, use: debuginfo-install 
hunspell-1.2.15-2.fc15.x86_64 nss-mdns-0.10-9.fc15.x86_64
-(gdb) 
-(gdb) 
-(gdb) bt
-#0  abort () at emacs.c:383
-#1  0x0000000000418f01 in matrix_row (matrix=0xac29400, row=-1)
-    at dispnew.c:1477
-#2  0x000000000046e113 in draw_glyphs (w=0x18235c0, x=198, row=0xa3af100, area=
-    TEXT_AREA, start=17, end=18, hl=DRAW_CURSOR, overlaps=0) at xdisp.c:22550
-#3  0x000000000047869f in draw_phys_cursor_glyph (w=0x18235c0, row=0xa3af100, 
-    hl=DRAW_CURSOR) at xdisp.c:24882
-#4  0x00000000005083bb in x_draw_window_cursor (w=0x18235c0, glyph_row=
-    0xa3af100, x=180, y=361, cursor_type=0, cursor_width=1, on_p=1, active_p=1)
-    at xterm.c:7440
-#5  0x00000000004790cd in display_and_set_cursor (w=0x18235c0, on=1, hpos=17, 
-    vpos=19, x=180, y=361) at xdisp.c:25098
-#6  0x00000000004fa31f in x_update_window_end (w=0x18235c0, cursor_on_p=1, 
-    mouse_face_overwritten_p=0) at xterm.c:644
-#7  0x000000000041ccb9 in update_window (w=0x18235c0, force_p=0)
-    at dispnew.c:3694
-#8  0x000000000041c165 in update_window_tree (w=0x18235c0, force_p=0)
-    at dispnew.c:3331
-#9  0x000000000041beee in update_frame (f=0x1658460, force_p=0, 
-    inhibit_hairy_id_p=0) at dispnew.c:3258
-#10 0x0000000000450a2e in redisplay_internal () at xdisp.c:12983
-#11 0x000000000044e2a6 in redisplay () at xdisp.c:12099
-#12 0x000000000056a60d in read_char (commandflag=1, nmaps=6, maps=
-
-** DONE allow xwidgets to report their size
-   CLOSED: [2011-07-19 Tue 14:26]
-now we just hard code sizes. but webkit widgets for instance can
-report sizes that suit the content. support that.
-** DONE BUG xwidget view ghosts
-   CLOSED: [2013-04-05 Fri 23:35]
-(havent seen this in quite a while)
-- xwidget-webkit-browse-url somewhere
-- split window.
-now theres 2 webkit views
-- c-x 1
-now theres 2 views but one is a ghost!
-one should have been deleted when its window died but that didnt work
-for some reason here.
-
-- m-x xwidget-cleanup
-
-the ghost goes away because we killed explicitly but this is just a workaround.
-
-xwidget_view_delete_all_in_window(w); in delete-window-internal is not 
sufficient.
-delete-other-windows-internal
-delete_all_subwindows
-unshow_buffer
-
-Added cleanup those window configuration hook which works in practice
-but feels kludgy.
-
-*** code looks like this
-
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-(defun xwidget-cleanup ()
-  "Delete zombie xwidgets."
-  ;;its still pretty easy to trigger bugs with xwidgets.
-  ;;this function tries to implement a workaround
-  (interactive)
-  (xwidget-delete-zombies) ;;kill xviews who should have been deleted but 
stull linger
-  (redraw-display);;redraw display otherwise ghost of zombies  will remain to 
haunt the screen
-  )
-
-
-
-;;this is a workaround because I cant find the right place to put it in C
-;;seems to work well in practice though
-(add-hook 'window-configuration-change-hook 'xwidget-cleanup)
-
-*** but it ought rather to work like this
-xwidget-delete-zombies should be called from C after window
-configuration has changed but before redisplay. redisplay should not
-be called.
-
-
-** DONE BUG annoying backtrace
-   CLOSED: [2011-07-19 Tue 14:28]
-(this no longer seems to happen even under heavy usage. seems merging
-from trunk helped. lots were happening in redisplay at this time in trunk.)
-
-sadly happens a lot.
-- happens even with no initialized xwidgets
--                   + row->glyphs[area][i].face_id
-or similar code, so row is invalid for some reason.
-xwidgets currently disable some redisplay opimizations so it might be
-an actual emacs bug manifesting without optimizations.
-
-*** bt 1
-      /* Compute the width of this line.  */
-      row->pixel_width = row->x;
-      for (i = 0; i < row->used[TEXT_AREA]; ++i)
-       row->pixel_width += row->glyphs[TEXT_AREA][i].pixel_width;
-
-(gdb) bt
-#0  0x000000000045c340 in compute_line_metrics (it=0x7fffffff8a20)
-    at xdisp.c:17549
-#1  0x00000000004603da in display_line (it=0x7fffffff8a20) at xdisp.c:18792
-#2  0x0000000000457646 in try_window (window=23403045, pos=..., flags=1)
-    at xdisp.c:15399
-#3  0x00000000004559c9 in redisplay_window (window=23403045, just_this_one_p=0)
-    at xdisp.c:14944
-#4  0x0000000000450247 in redisplay_window_0 (window=23403045) at xdisp.c:13152
-#5  0x00000000005fdcd9 in internal_condition_case_1 (bfun=
-    0x450208 <redisplay_window_0>, arg=23403045, handlers=12691046, hfun=
-    0x4501d9 <redisplay_window_error>) at eval.c:1538
-#6  0x00000000004501ba in redisplay_windows (window=23403045) at xdisp.c:13132
-#7  0x000000000044f19c in redisplay_internal () at xdisp.c:12706
-#8  0x000000000044f9f2 in redisplay_preserve_echo_area (from_where=7)
-    at xdisp.c:12964
-#9  0x0000000000568525 in swallow_events (do_display=1) at keyboard.c:4197
-#10 0x0000000000422554 in sit_for (timeout=40, reading=1, do_display=1)
-    at dispnew.c:5963
-#11 0x000000000056512c in read_char (commandflag=1, nmaps=8, maps=
-    0x7fffffffd3f0, prev_event=12720514, used_mouse_menu=0x7fffffffd604, 
-    end_time=0x0) at keyboard.c:2689
-#12 0x0000000000572c59 in read_key_sequence (keybuf=0x7fffffffd850, bufsize=
-    30, prompt=12720514, dont_downcase_last=0, can_return_switch_frame=1, 
----Type <return> to continue, or q <return> to quit---
-    fix_current_buffer=1) at keyboard.c:9291
-#13 0x0000000000562897 in command_loop_1 () at keyboard.c:1446
-#14 0x00000000005fdb52 in internal_condition_case (bfun=
-    0x5624b4 <command_loop_1>, handlers=12772898, hfun=0x561dab <cmd_error>)
-    at eval.c:1493
-#15 0x00000000005621ab in command_loop_2 (ignore=12720514) at keyboard.c:1157
-#16 0x00000000005fd4ce in internal_catch (tag=12768770, func=
-    0x562185 <command_loop_2>, arg=12720514) at eval.c:1247
-#17 0x000000000056215e in command_loop () at keyboard.c:1136
-#18 0x00000000005618f9 in recursive_edit_1 () at keyboard.c:757
-#19 0x0000000000561a95 in Frecursive_edit () at keyboard.c:821
-#20 0x000000000055fba2 in main (argc=1, argv=0x7fffffffe188) at emacs.c:1704
-
-
-*** bt 2
-
-** DONE Examine using XComposite rather than GTK off-screen
-  rendering. This would make xembed widgets work much better. This
-  would probably be rathter difficult, but could open up other
-  interesting possibilities for Emacs. There is an early attempt in
-  xwidget.c, but the X call to redirect to offscreen rendering fails
-  for unknown reasons.
-
-  the attempt was further worked on, and the xlib calls replaced with
-  gdk calls, this works better.
-
-  In the end I abandoned this aproach. Xwidget-osr is the new aproach.
-
-** TODO  make the keyboard event code propagation code work. 
-There is an attempt to provide an api to send keyboard events to an
-xwidget, but it doesnt currently work very well.
-
-*** TODO try gtk event creation instead 
-since that works fine in the webkit osr code. 
-but, oh no, that didn't work for some reason.
-the widgets seems to receive the event but then the embedded widgets
-hangs.
-
-http://kegel.com/gtk/button.c
-
-*** TODO examine some library to synthesize events
-xdotool
-xte xautomation
-crikey
-libxdo
-
-*** TODO webkit raw keyboard event escape
-c-c tab could send a raw tab to the webkit instance.
-** DONE remove the special-case for when the minibuffer is
-  active.  I added some code to reduce the annoying problem display artefacts
-  when making the minibuffer the selected window. This made xwidgets in the
-  buffer go grey or black whenever one did m-x to activate the minibuffer. The
-  coded tried to handle the minibuffer as a special case. That simply wasnt a
-  good idea. Special-casing will never work properly. It is much better to 
spend
-  time finding solutions that work acceptably in the general case.
-
-** DONE disable emacs cursor drawing on top of an active xwidget. 
-  This ought to be rather simple and should improve the visuals a lot.
-
-** TODO  improve the xwidgets programming interface 
-so its less of hand-waving affair. This shouldnt be too hard, but I
-  have deliberatley not spent any time on it, since getting the
-  visuals right is much harder. Anyway, I sort of think the interface
-  should be somewhat like it is, except symbols is used instead of
-  integers.
-*** DONE use symbols for xwidget types rather than ints
-    CLOSED: [2011-06-27 Mon 12:52]
-
-
-*** TODO better lisp based structure for xwidgets
-the lisp interface woud be like this:
-- make-xwidget returns an xwidget object, similar to a process
-  object. this object is used when creating the display spec(instead of
-  the user defined id now used)
-
-the data structure would be something like this:
-- a "process" like aproach to create the xwidgets. xwidgets are
-  coupled to buffers, somewhat like processes, except a buffer can
-  hold several xwidgets
-- an xwidget has a plist to hold the model, like a process
-- an xwidget has an assoc list of xwidget views
-
-there are some things that arent clear:
-- an xwidget doesnt necessarily need to be coupled to a buffer but it
-  seems to be the clearest model. xwidgets would be buffer local
-- xwidget-views are by necessity coupled to a emacs window so it might
-  be better to store them window locally rather than in an assoc
-  coupled to the xwidget model
-- for some gtk widgets that resist an mvc approach, like the webkit
-  widgets, special operations are needed, similar to the old phantom
-  widgets aproach. so we need to differentiate live and phantom
-  instances for these troublesome widgets and let lisp manage all the trickery.
-
-stuff that needs to work:
-- do something for all views of a xwidget(resize, value change)
-- do something for all xw-views in an emacs window(deletion etc)
-- lookup xw-view for xwidget in emacs window(during redisplay)
-(- do something for all siblings of a xw-view. not atm)
-
-*** DONE xwidget creation interface
-    CLOSED: [2011-07-18 Mon 01:59]
-xwidgets are a little bit like emacs processes but also a little bit
-like emacs images. Therefore its not perfectly obvious how to handle
-creation. Currently I just use hardcoded identifiers. the real scheme
-needs to be something else.
-
-Heres a tentative approach:
-- xwidget-create returns a xwidget object, like process creation
-  functions. the xwidget will be largely uninitialized until
-  discovered by redisplay. an xw belongs to a buffer
-- xwidget-insert inserts the xwidget in a buffer. when discovered by
-  redisplay it will be initialized and a xwidget-view allocated
-- an event will be emitted when initialization is finished when
-  relevant like for sockets
-
-the problem with this aproach is that its not really legal to reuse
-xwidget objects by writing several display specs who reference the
-same xwidget. It could presumably be done but it would just become
-weird for no real benefit. the big preblem is that the display spec
-decides the on-screen size, and its not sane to have xwidget views
-with different sizes. therefore such display specs would need to be
-catched and dissallowed. Except it is hard because AFAIK the specs
-don't have an identity as such. A flag in the structure could be set
-by lookup so the first display attempt would win. but then you can't
-rewrite the spec to change the size. hmmm. A third approach would be
-to just allow the 1st spec refering an xw during a redisplay to take
-effect, the rest are signaled as errors. this wouldnt be too bad.
-
-the other aproach would be to work more like images:
-
-- write the display spec with all information needed to create the
-  xwidget.
-- retrieve the xwidget objet from the spec with an xwidget-at-point function. 
It
-  can be uninitalized which client code must handle. Unlike
-  asynchronous process creation we dont get back a handle, because
-  there is none yet.
-- emitted event on initialization, when needed. Many widgets don't
-  need this. for instance, a button sends an event when pressed. but
-  you can't press it unless its on screen, and then its initialized
-  properly. 
-
-This approach seemed good, but how do I know which instance
-generates an event if I cant set the id beforehand?
-
-so, therefore, the first two aproach is used. 
-
-
-*** DONE xwidget creation interface actually
-    CLOSED: [2011-07-18 Mon 01:59]
-conclusion of above ramblings:
-- should be similar to make-text-button
-- don't init from display spec, instead during make-xwidget call
-*** TODO callbacks would be nice 
-but they need to be handled initially with events for technical
-reasons. C code can't call Lisp easily. The event handler can call the
-callback though.
-
-** TODO  more documentation
-There should be user docs, and xwidget contributor docs. The current README
-is all contributor docs there is now, apart from the code.
-
-
-
-** CANCELLED look into more ways of displaying xwidgets, like binding them to a
-   CLOSED: [2011-07-05 Tue 11:34]
-window rather than a point in a buffer. This was suggested by Chidong.
-This would be a useful addition to Emacs in itself, and would avoid nearly all 
-display issues. I still think the general case is more interesting, but this
-special case should also be added. The xwidget would then be bound to
-replace the view of a particular window, and it would only show in
-that window.
-
-I got the webkit xwidget to work well enough so I dont see the need
-for this now, except for sockets and I think it can better be dealt
-with at the lisp level.
-
-** DONE MVC mode for xwidgets
-   CLOSED: [2011-06-27 Mon 12:53]
-It appears unfruitful to chase using the same display mode for all
-types of xwidgets. Composition is fun but not robust the way I
-tried to do it.
-
-Instead there should be a set of MVC xwidgets. Each on-screen instance
-of an MVC widget would be a real GTK widget. The instances would
-communciate state using signals. 
-
-There are drawbacks. There is no inbuilt support for MVC in GTK, so we
-have to roll our own, which is tedious if not much work for the few
-cases.
-
-MVC for xembedded application will need support from the applications
-themselves. Inkscape supports multiple views to the same document,
-other programs don't. In practice it might not be a big drawback.
-
-
-*** DONE figure out what to do with the multiple frames case. 
-    CLOSED: [2011-06-27 Mon 12:52]
-This should be easier to solve with MVC.
-Surprisingly, this just worked!
-*** DONE how to propagate changes in views to other views?
-    CLOSED: [2011-06-27 Mon 12:53]
-I used gtk signals, the implementation for sliders works well!
-
-** TODO canvas support
-heres an interesting comparision of gtk canvases
-http://live.gnome.org/ProjectRidley/CanvasOverview
-
-ATM there are small hardcoded demos in the code, these should be
-removed and replaced with working xwgir counterparts.
-*** goocanvas
-goocanvas is a gtk canvas implemented using cairo. investigate.
-
-pros:
-- it has a MVC model aproach out of the box which is nice.
-
-http://developer.gnome.org/goocanvas/unstable/goocanvas-model-view-canvas.html
-
-export CFLAGS="`pkg-config --cflags goocanvas` -DHAVE_GOOCANVAS"
-export LDFLAGS=`pkg-config --libs goocanvas`
-./configure
-make
-
-I made a hello goo world xwidget so seems doable.
-I wanted to load a SVG which wasnt immediately straightforward, so I
-tried clutter. but it turns out the exact same strategy could be used
-with goocanvas.
-
-*** clutter
-maybe clutter can be used as a canvas? 
-pros:
-- seems to have a lot of traction atm. many examples
-- potentialy fast and cool vector graphics
-cons:
-- no out of the box MVC support, but seems doable. no worse than the
-  other home brew mvc support I have in xwidgets
-(media-explorer in an application that employes the MVC pattern)
-
-http://www.openismus.com/documents/clutter_tutorial/0.9/docs/tutorial/html/sec-stage-widget.html
-
-there is also cool stuff like this:
-http://gitorious.org/webkit-clutter/webkit-clutter which is an webkit actor for
-clutter! hmmmmm.
-
-I want to render svg. aparently:
-  librsvg rsvg_handle_render_cairo(h, cr);
-  ClutterCairoTexture
-  Clutter
-
-export CFLAGS="`pkg-config --cflags clutter-gtk-1.0` -DHAVE_CLUTTER"
-export LDFLAGS=`pkg-config --libs clutter-gtk-1.0`
-./configure
-make
-
-compiles but I get:
-Gtk-ERROR **: GTK+ 2.x symbols detected. Using GTK+ 2.x and GTK+ 3 in
-the same process is not supported
-
-export CFLAGS="`pkg-config --cflags clutter-gtk-0.10` -DHAVE_CLUTTER"
-export LDFLAGS=`pkg-config --libs clutter-gtk-0.10`
-./configure
-make
-
-
-*** webkit html 5
-expose the DOM to lisp or something. The webkit xwidget works pretty
-well now, so this might be the way ahead.
-** DONE mvc code crashes after a while
-   CLOSED: [2011-07-12 Tue 18:52]
-seemingly only when compiling with optimizations.
-I have no idea why.
-
-Doesn't seem to happen after some code cleanups.
-** DONE xwidget-resize-at
-   CLOSED: [2011-07-19 Tue 14:28]
-reimplement so display spec is not involved
-** DONE display spec validation
-   CLOSED: [2011-07-19 Tue 14:44]
-it is an error to reuse xwidgets in several buffers or in the same
-buffer. how do we catch these errors? 
-- showing the same xwidget twice in a buffer is no more wrong than
-  showing in several emacs windows, just conceptually wrong, so ignore
-  this case for now
-- xwidgets now store a reference to the buffer they were created in,
-  so use that to invalidate xwidget references in oher buffers. but
-  thats not really an error either
-- xwidgets should now be proper lisp objects so you dont delete them
-  you await their garbage collection. so therefore there can never be
-  invalid display specs
-
-so turned out this got solved by using proper lisp objects for
-xwidgets. yay!
-
-** DONE clipping of controllers
-   CLOSED: [2011-07-05 Tue 11:33]
-
-Emacs uses a big GTK window and does its own clipping against Emacs
-windows inside this area. So, in order to layout gtk widgets in emacs
-windows we must clip thim ourselves. 
-
-The following method worked well for a long time:
-- make a gtk widget, say a button, xw
-- make a clipping area, of type gtkfixed(many types have been tested)
-- put the clip area in the main emacs gtk window
-- figure out clip area changes during emacs redisplay
-
-the only weirdness was that one has to tell gtk the clip area has a
-window in order to get clipping. This is weird because all gtkwidgets
-are windows in a sense and a window is almost by definition also a
-clipping area.
-
-Anyway, in GTK3 the   gtk_widget_set_has_window(GTK_WIDGET (
-xv->widgetwindow), TRUE); call is ignored. 
-
-The gtkeventbox which is documented to have its own window doesnt work
-either.
-
-http://www.lanedo.com/~carlos/gtk3-doc/chap-drawing-model.html
-
-anyway clipping is rather complicated but seems to finally work okay.
-
-*** DONE subclass my own clipping widget
-    CLOSED: [2011-07-04 Mon 16:55]
-http://www.lanedo.com/~carlos/gtk3-doc/GtkWidget.html#gtk-widget-set-has-window
-mentions that it has_window can only be called inside a widget
-implementation.
-
-this wasnt really the issue. allocation was the problem
-*** DONE try scrolled window
-    CLOSED: [2011-07-01 Fri 10:56]
-clipping does in fact work with
-gtk_scrolled_window_add_with_viewport (xv->widgetwindow, xv->widget);
-!!
-
-I get unwanted scrollbars in the widget though.
-
-  gtk_scrolled_window_set_policy      (  xv->widgetwindow,
-  GTK_POLICY_NEVER, GTK_POLICY_NEVER); 
-
-stops clipping from working! 
-
-
-*** DONE try viewport
-    CLOSED: [2011-07-01 Fri 10:56]
-gtkviewport is used in scrolled window so in order to remove
-scrollbars it should be possible to use viewport directly. however, 
-viewport ignores size requests. or rather the container does.
-
-
-*** DONE debug allocation
-    CLOSED: [2011-07-04 Mon 16:56]
-the container determines how much size to allocate to child widgets.
-
-        GtkAllocation galloc;
-        gtk_widget_get_allocation(GTK_WIDGET (xv->widgetwindow), &galloc);
-        printf("allocation %d %d , %d %d\n", 
galloc.x,galloc.y,galloc.width,galloc.height);
-
-after my clipping attemp shows that my size request is ignored! this
-might be logical, since the container provided by emacs is a
-gtkfixed. gtkfixed might choose to heed the widgets size desires and
-allocate the entire widget size. but we want clipping!
-
-since i cant reasonably expect to change the emacs main container, i
-can maybe overide the setallocation method in gwfixed, and adjust
-allocation to clipping if its an xwidget asking for allocation.
-
-**** DONE subclass gtkfixed
-     CLOSED: [2011-07-04 Mon 16:56]
-possibly i need to subclass gtkfixed and override
-#+begin_src C
-  void                gtk_widget_size_allocate            (GtkWidget *widget,
-                                                           GtkAllocation 
*allocation);
-#+end_src
-http://developer.gnome.org/gobject/stable/howto-gobject.html
-
-turns out emacs already does this for gtk3 according to jan D:
->>For GTK3, Emacs already subclasses GtkFixed, see emacsgtkfixed.[ch].
-
-- widgets may not be underallocated, aparently
-http://mail.gnome.org/archives/commits-list/2011-April/msg10950.html
-
-- how to call base class method/chain up
-http://developer.gnome.org/gobject/stable/howto-gobject-chainup.html
-
-- the allocation modification could happen in the container or the
-  child. it feels more apropiate in the container
-
-it is however unexpectedy inconvenient to modify allocation because
-the needed data is private to the base class. to overcome this:
-
- - run base class method 1st. 
- - then, iterate all children, and modify allocation  for xwidget
-   children only. x y will then be set.
-
-JanD pointed out the GTK3 port already has its own subclass, so I
-modified that one.
-
-*** DONE clip top
-    CLOSED: [2011-07-05 Tue 11:30]
-there are four controller edges that potentialy need clipping. I begun
-with right and bottom edges. clipping them is just a matter of setting
-the right size of the widgetwindow and also ensure it gets the right
-allocation from the container.
-
-clipping top (and left) is not equally straightforward. I'm using a
-viewport now and scroll it the amount that needs to be clipped.
-however, the viewport is sensitive to changes in allocation, which
-makes it harder to use the allocation workarounds.
-
-see:
-- gtk_widget_set_size_request
-- gtkscrolledwindow
-
-I returned to using a simple gtkfixed for the widgetwindow. with
-allocation hack and set_has_window it works. Idea prefer not to have
-the allocatien hack and it wasnt needed it gtk3 only gtk2. needs
-further investigation.
-
-** various code cleanups
-There are many cleanups necessary before any hope of inclusion in
-Emacs trunk. To begin with, the part of the patch that touches other
-parts of emacs must be very clean. 
-*** DONE use FRAME_GTK_WIDGET (f)
-    CLOSED: [2011-07-20 Wed 20:02]
-rather than gwfixed.
-
-*** DONE support configure
-    CLOSED: [2011-07-12 Tue 18:48]
-*** DONE ifdef all xwidget code
-    CLOSED: [2011-08-13 Sat 16:19]
-so you can reliably disable the code at compiletime
-** DONE translate clicks 
-   CLOSED: [2011-07-03 Sun 22:12]
-on onscreen webkit peer to offscreen
-
-maybe
-http://developer.gnome.org/gdk/stable/gdk-Windows.html#GdkWindow-from-embedder
-
-turned out to be not so hard, captured events, copied them and
-forwarded them offscreen!
-
-** CANCELLED investigate gdk_window_redirect_to_drawable
-   CLOSED: [2013-04-05 Fri 23:37]
-(cancelled this, the current approach seems okay)
-http://developer.gnome.org/gdk/stable/gdk-Windows.html#gdk-offscreen-window-set-embedder
-maybe could be used in place of my own copy hacks? to work it must
-support a chain of redirects, which seems unlikely. the benefit would
-be that I dont have to spend time optimizing redrawing.
-
-
-** DONE remove xwidget_views when emacs window is deleted
-   CLOSED: [2011-07-05 Tue 11:29]
-removing xwidget views when an Emacs window closes is not reliable.
-
-- switching buffers in a window seems to hide the corresponding
-  xwidget-views properly, but they might as well be deleted.
-
--  patching delete-window-internal could be used to delete the xwidget-views
-this seems to work
-
-
-** browser xwidget
-although embedding a browser is not my primary concern many are
-interested in this. some suitable browser component needs to be found
-supporting gtk.
-
-*** DONE webkit
-    CLOSED: [2011-07-03 Sun 22:13]
-there is a webkit gtk port. there is no obvious mvc support.
-http://live.gnome.org/WebKitGtk
-http://webkitgtk.org/
-
-it might be possible to keep a set of webxits in artificial
-synchronisation by recursive deep copy of the DOM from one webkit to
-another. This will be error prone at best though. Another way might be
-to just use bitmap copy of the "live"instance to the "phantom"
-instances. the problem of transfering the live view remains though.
-
-export CFLAGS="`pkg-config --cflags webkit-1.0` -DHAVE_WEBKIT -g"
-export LDFLAGS=`pkg-config --libs webkit-1.0`
-./configure
-make
-
-**** off screen rendering
-export CFLAGS="`pkg-config --cflags webkit-1.0` -DHAVE_WEBKIT_OSR -g"
-export LDFLAGS=`pkg-config --libs webkit-1.0`
-./configure
-make
-
-works a little bit  but i get errors like:
-
-(emacs:8362): GLib-GObject-WARNING **: invalid cast from `GdkOffscreenWindow' 
to `GdkDrawableImplX11'
-
-set a breakpoint in g_log, backtrace seems to indicate
-webkitViewportAttributesRecompute is the offender. 
-
-maybe try gtk3 variants?
-#+begin_src sh
-  export CFLAGS="`pkg-config --cflags webkitgtk-3.0 ` -DHAVE_WEBKIT_OSR "
-  export LDFLAGS=`pkg-config --libs webkitgtk-3.0 `
-  ./configure   --with-x-toolkit=gtk3
-  make
-#+end_src
-crash in gtk_window_get_size instead. great.
-
-http://gtkplus-p3.0.sourcearchive.com/documentation/2.91.5-0ubuntu1/testoffscreenwindow_8c-source.html
-
-after many attempts, the basic issue remains. for some reason the
-offscreen widget isnt ok when I want to snapshot it, so i simply get
-emptiness. the surface is only ok sometimes.
-
-here is a useful debugging snippets:
-#+begin_src C
-  // debugging redraw:
-  //  - the bg colors always change, so theres no error in signal handling
-  //  - i get this error now and then:
-  //(emacs:7109): GLib-GObject-WARNING **: invalid cast from 
`GdkOffscreenWindow' to `GdkDrawableImplX11'
-  // seems to happen in webkit actually. see README
-  
-  if(0){ //redraw debug hack. helped a lot in fact. use the with alpha painter 
below also
-    cairo_set_source_rgb(cr, osr_dbg_color, 1.0, 0.2);
-    cairo_rectangle(cr, 0,0, xw->width, xw->height);
-    cairo_fill(cr);
-    osr_dbg_color+=0.1;
-    if(osr_dbg_color>1.0)
-      osr_dbg_color=0.0;
-    
-  }
-#+end_src
-you need to terminate drawing like this:
-#+begin_src C  
-  //cairo_set_source_surface (cr, src_pixmap, 0,0); 
-  //cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
-
-  //cairo_paint_with_alpha (cr, 1.0);
-  //cairo_paint(cr);
-#+end_src
-
-the snippets change background color on oach redraw. 
-
-**** on-screen rendering to separate window
-an alternative might be to open a separate window and snapshot it. the
-idea is that whatever oddness webkit does so that offscreen rendering
-doesnt work, doesnt happen on-screen. the window could be opened
-somewhere not in the way.
-
-*** CANCELLED firefox
-    CLOSED: [2011-07-03 Sun 22:13]
-http://www-archive.mozilla.org/unix/gtk-embedding.html
-seems to be severly bitrotted
-
-heres a newer aproach
-http://hg.mozilla.org/incubator/embedding/file/29ac0fe51754/gtk/tests/test.cpp
-
-while webkit clearly has the best traction as an embedded, the
-offscreen rendering issues makes it interesting to see what ff brings
-to the table. 
-
-turned out webkit has as good offscreen support as anyone, see I went
-with that in the end.
-
-
-*** DONE text field support
-    CLOSED: [2011-07-20 Wed 20:05]
-Emacs captures all keyboard events so text field support isn't super
-straightforward. 
-
-**** propagate keyboard events
-I have some old hacks for this and they are not good.
-**** use the DOM model
-expose document.activeElement to lisp. This is potentially more
-interesting than just forwarding keyboard events.
-
-webkit_web_view_get_dom_document ()
-
-this is hard it seems. an idea might be to hack elisp support for swig
-to machine generate the bindings. 
-**** DONE inject javascript
-     CLOSED: [2011-07-03 Sun 22:50]
-webkit_web_view_execute_script ()
-
-this works now:
-(xwidget-webkit-execute-script 5 "document.activeElement.value='test'")
-
-so it should be possible to do some interesting stuff.
-execute-script does however not return anything at the interface level
-so satisfaction is not total:
-
-http://markmail.org/message/4yowmdgras73z3x5
-
-maybe
-https://launchpad.net/gnome-seed
-
-or this funny hack:
-<jave> im trying to understand how to interact via javascript to an embedded
-       webkit gtk instance  [23:38]
-<jave> i use webkit_web_view_execute_script() which is nice but doesnt return
-       a value, by design aparently  [23:39]
-<jave> any hints?
-<lucian> jave: afaik, webkit still doesn't have full gobject bindings  [23:48]
-<lucian> jave: you can hack it up by making the JS modify the title, and read
-         the title from gtk-side
-<jave> lucian: that was a pretty cool idea!
-
-
-*** webkit_web_view_load_string ()
-I would like preview of html in a buffer rather than from uri.
-
-
-
-*** DONE simple xwidget-webkit wrapper
-    CLOSED: [2011-07-22 Fri 11:01]
-so that it could be used for actual browsing :)
-I dont want to reinvent too many wheels so i'd like to use existing
-emacs facilities here possible. use bindings similar to w3m(or info)
-
-- m-x xwidget-webkit starts a session
-- 'g' goes to a url
-- use bookmark-jump i suppose. I mostly use org for bookmarks myself
-- browse-url support so webkit can be the default browser
-- some way of getting around the quirky keyboard interaction since
-  xwidgets dont receive keyboard events because I hawe no idea how to
-  do that in a sane way
-
-... and one can of course go on bikeshedding forever. lets keep it
-simple and extensible, and compatible with other Emacs packages.
-
-the really cool ideas would need Emacs DOM integration, which is not
-easy. 
-
-** webkit related
-*** TODO webkit support webkit signals
-
-**** DONE particularly document-load-finished
-     CLOSED: [2011-08-01 Mon 22:34]
-http://webkitgtk.org/reference/webkitgtk-webkitwebview.html#WebKitWebView-document-load-finished
-because one might need tell set a title and sizes and things when it loads.
-**** TODO event bug
-Debugger entered--Lisp error: (error "Two bases given in one event")
-
-hapens sometimes with xwidget events. appears to be when the
-originating xwidget is offscreen so that the event doesn't get caught
-by the correct emacs event map.
-
-maybe I need to set the originating window in the event structure.
-  event.frame_or_window = Qnil;        //frame; //how to get the frame here? 
//TODO i store it in the xwidget now
-
-since its an offscreen xwidget the buffer local keymap isnt the right
-place for the handler. some global map should be used.
-
-onscreen widgets don't have the same issue.
-
-anyway, seems it'll turn out like this:
-- xwidget-osr stores a callback and user data
-- the event is an implementation detail only and get caught in the
-  topmost event map
-- the event map calls the callback in the xw with the right args.
-
-we need the event handler at some level because we can't call lisp
-asynchronously. 
-
-**** TODO navigation signal
-**** TODO new window signal
-*** TODO console messages
-http://webkitgtk.org/reference/webkitgtk-webkitwebview.html#WebKitWebView-console-message
-http://getfirebug.com/wiki/index.php/Console_API#console.count.28.5Btitle.5D.29
-because maybe we can make a simple JS REPL that way.
-  (xwidget-webkit-execute-script ( xwidget-webkit-last-session)
-  "console.log('hello')")
-prints hello to stdout but theres no way to catch stdout from webkit I
-think other than receiving the signal.
-
-*** TODO webkit flashkiller by default
-while its possible to support plugins in the webkit xwidget, flash has
-issues on 64 bit, and slows down emacs to a halt with off screen
-rendering, and of course is not free software. its in the way for real
-world usage even if its interesting to watch flash animations inside
-emacs. which should be achieved with Gnash or other free software
-instead.
-
-http://stackoverflow.com/questions/4885513/prevent-flash-in-cocoa-webview
-
-simply use this api:
-http://webkitgtk.org/reference/WebKitWebPluginDatabase.html
-
-theres an implementation now but it's not robust enough webkit often
-crashes taking emacs with it.
-
-*** TODO webkit downloads
-when clicking a download link in Webkit Emacs should take over and handle it
-from there. Probably need signals. There are Emacs libraries to
-download things, with wget etc. an url.el facility should be made.
-"download-requested"
-*** TODO webkit alt-text not handled
-XKCD use image-title to display a cartoon comment. These mysteriously
-don't work ATM. Other mouseovers work though. Maybe webkit tries to
-open a new window or something, which wont work.
-
-*** TODO webkit isearch in webkit buffers
-have a look at how docview solves it
-webkit_web_view_search_text ()
-*** TODO webkit relative references doesn't work
-because we handle scrolling in a non-standard way. It does
-work sort of when theres a html frameset and webkit scrolls by itself.
-
-internal links (page.html#section) do not work
-see xwidget-webkit-show-named-element
-
-also did some  webkit signal work for this.
-
-now it actually works! except for I need to know the Y coordinate of
-the element to navigate to, and that can either be by "name" or "id"
-attribute, currently "id"  works.
-
-
-
-*** TODO webkit width adjustment handling issue
-since there are so many levels of clipping and whatnot in xwidgets
-sizing issues are difficult.
-
-- an xwidget is told how large it can be by emacs. thats the end of
-  it. if the xwidget thinks otherwise it will be clipped.
-- but emacs can ask the xwidget how large it wants to be. it can then
-  resize the reserved area and inform the xwidget thusly. 
-
-That should have been enough. but webkit never reports less than what
-it already has. So currently a webkit view will only growth and not
-adjust to smaller sizes. 
-
-This is not a big problem in practice but is still annoying.
-
-to see the problem surface to http://www.slashdot.org
-- xwidget-webkit-adjust-size
-- xwidget-webkit-adjust-size-to-content
-
-and then compare by resizing in Epiphany, which is also webkit based.
-
-**** TODO try putting webkit osr inside a scrolling window
-it seems webkit is supposed to behave differently while embedded in a
-scrolling window. This is a bit cumbersome because the container stack
-is already deep.
-*** TODO xwidget webkit allow loading from string from emacs
-*** DONE xwidget-webkit-last-session
-    CLOSED: [2011-08-01 Mon 22:38]
-was rather hurried. end result is that the lisp layer only really
-allows for one webkit session.
-*** TODO extract DOM to lisp
-then the SHR html renderer from Gnus could render the DOM as created
-by Webkit. 
-
-made a simple oxperimental DOM tree traverser. It can be expanded to
-return a lisp representation, LDOM.
-
-in order to bring lisp and DOM closer together the LDOM can include a
-mapping to the originating DOM node. so, find a node in LDOM, and the
-cell maps to the original DOM. but since the LDOM is a copy it can get
-out of sync. DOM events might help.
-*** DONE C-X b in other buffer from webkit
-    CLOSED: [2011-08-12 Fri 22:20]
-bafflingly resets the webkit view to the top. Maybe the window
-reconfiguration hook code? further mystification is added because it
-only seems to happen with ido mode enabled.
-
-in comparison with image-mode which does the right thing, I discovered
-that image-mode has special code to handle scrolling. the browser mode
-and image mode has some similarities.
-
-I made some delegation code frrom webkit mode to image mode.
-*** TODO url-browse improvement
-sindikat: site.com and http://site.com should be equivalent (simple site.com
-  throws error)
-
-Yes, but its unclear at what level in Emacs to do this
-properly. I added a url-tidy function as a start.
-
-this should be further improved:
-- change the call to url-tidy so its a hook
-- provide a couple of demonstration hooks:
-  - url-tidy, which just prepends http://
-  - youtube which appends &html5=1 to urls looking like 
http://www.youtube.com/watch?v=DZdUgjEx_dQ
-  - history which logs all visited urls like a traditional browser
-
-*** TODO sindicat notes
-Here are some comments from user "sindikat" and my replies
-
-- http://ya.ru renders inadequatly (compare with any other browser) -
-  the search text-input is way below
-
-The problem is the size communication between Emacs and Webkit. 
-
-- doing PageDown is endless; so if you do 100 PageDowns, you have to
-  do 100 PageUps to retun to the header of the page
-
-True, I hadn't noticed. Thanks.
-
-- http://linux.org.ru (just an example) renders incorrectly too - it
-  should stretch horizontally
-
-Size communication.
-
-- obviously, pointing of mouse over some link should change it to
-  pointing hand cursor
-
-Need to verify with some other webkit browser.
-
-- when you are somewhere on the middle of a long page, than go to some
-  other page, you are still in the middle, instead of being again on
-  the top
-
-This is because I inherit from Image view mode. I kind of like it so
-we can add an option for it.
-
-
-- changing dropdown menus cause flickering
-
-
-- string entering is incorrect - by default it enters the title of the
-  page, while it should be empty
-
-The cause is the lack of return value in the webkit evaluation
-API. Ive made some fixes.
-
-- internal links (page.html#section) do not work
-
- ive added a rudimentary function "xwidget-webkit-show-named-element" for this
-
-- maybe it's a good idea to implement Conkeror or some other
-  keybindings, where you press 'f' then select the exact <input
-  type="text"> where you want to enter text, without using mouse,
-  etc.;
-
-Indeed, this would require better DOM integration.
-
-- pressing 'home' and 'end' puts nonsense into minibuffer
-
-Probably because the Image mode derivative is mostly a hack.
-fixed now I think.
-
-
-
-
-
-
-- implement search (emacs internal isearch obviously doesn't work)
-
-Either use the webkit search but that doesn't feel right. It would be
-better to expose the DOM and search that.
-
-- some sites intercept with keyboard; example -
-  http://www.artlebedev.ru/kovodstvo/business-lynch/2011/10/03/ uses
-  Ctrl+left/right/up/down to navigate between pages - this should be
-  implemented too
-
-Keyboard integration is the unloved step-child of xwidgets, unfortunately.
-
-
-
-** TODO xwidget image display  spec compatibility
-some history: the first version of the xwidget display spec was
-the same as an image spec. This turned out not to be fantastic because
-an xwidget is both like a process and like an image. it has a separate
-existence from display. So now the xwidget display spec is just a
-pointer to a xwidget. But then some useful functionality in Emacs
-can't be reused for xwidget, in particular image-mode.
-
-Maybe a new image type could be added that was a wraper on an
-xwidget. Then image mode could be reused for webkit mode. 
-
-I tried some adaptor code in xwidget.el so webkit mode now delegates
-to image mode but its a kludge.
-
-** socket related
-*** TODO some flickering during redisplay of sockets
-with gtk3 an size allocation workaround is used.
-this seems maybe to result in flickering sizewize y-axis with the
-xwidget socket type. The webkit xwidget doesn't seem similarily
-afflicted.
-
-the size allocation workaround works by 1st running the ordinary
-allocation then modifying the results. its done this way to minimize
-the copy paste index from the base class. it might be that the
-original allocation has a brief time window to show itself.
-
-tried to modify the allocation hack so it doesn't call allocate
-twice. this doesn't seem to help flicker at all aparently so the
-hypothesis falls. Maybe then a socket simply doesn't like being clipped
-by gtkfixed. 
-
-*** TODO xwidget view reaping too agressive
-hide an emacs window for a while and return to it. the xwidget might
-get reaped and a new socket thus created.
-*** DONE try out OSR for sockets
-    CLOSED: [2011-07-25 Mon 21:30]
-
-didn't work too well in the inkscape case. it might be that some other
-bitmap copy method works better though.
-
-basically sockets doesn't like to be offscreen because they want their
-own gdk window.
-
-** DONE synchronise emacs background with xwidget color
-   CLOSED: [2011-08-11 Thu 11:04]
-fine-tuning to reduce flicker.
-
-isn't needed if emacs bg erase disabled
-
-** DONE xwidgets doesn't work during bootstrap all of a sudden
-   CLOSED: [2011-08-01 Mon 22:33]
-might be some annoying local issues with my install because it is not
-reliably reproducible. (went away during merges)
-
-** CANCELLED low impact xwidget based image viewer
-   CLOSED: [2013-04-05 Fri 23:38]
-(cancelled this because it no longer seems like a good idea)
-for instance to render SVG using webkit, or some other canvas.
-that way it would be possible to merge to trunk in stages.
-
-so, webkit could be used to display the SVG. the display spec for
-images would be used. multiple webkits would be used rather than
-offscreen rendering, so it would be GTK2 compatible. 
-** DONE xwidget movement doesn't work all of a sudden
-   CLOSED: [2011-08-11 Thu 11:03]
-this used to work great. now it doesn't.
-
-suspects:
-- XCopyArea
-  - x_shift_glyphs_for_insert
-  - x_scroll_run. this is run by the try_window* functions, and
-    inhibiting them doesnt help. but also callid in scrolling_window.
-  
-
-- try_window_reusing_current_matrix
-- I used to enable GLYPH_DEBUG which I currently don't. it disables
-  many optimisations. this was fixed.
-- lookup_xwidget then produce_xwidget_glyph gets called always but not 
-x_draw_xwidget_glyph_string probably because of scroll optimization. 
-movement detection could possibly be moved to produce_xwidget_glyph(not)
-
-no longer helps:
-(setq inhibit-try-window-id t)
-(setq inhibit-try-window-reusing t)
-
-workaround:
-(run-with-timer 1 1 'redraw-display)
-
-seems to work:
-inhibiting scrolling_window(). and this seem to be enough to restore the
-old behaviour, GLYPH_DEBUG doesn't seem needed.
-
-
-** DONE GLYPH_DEBUG doesn't work
-   CLOSED: [2011-08-08 Mon 17:30]
-was stupid accidental line removal that was hard to spot
-** TODO osc xwidget example  
-a couple of xwidget sliders that control a csound/supercollider song with osc.
-so, for that to work we need slider callbacks to work. when a slider
-changes send an osc message. use ocssend:
-
- oscsend localhost 7777 /sample/address iTfs 1 3.14 hello
-
-or better:
-http://delysid.org/emacs/osc.el
-
-sliders could be defined in csound comments or something to illustrate
-the point. or if real fanciness is desired parse the csound source
-with Semantic and provide a control buffer corresponding to the
-defined controls.
-
-
-
-Added: [2011-08-11 Thu 10:53]
-
-
-** DONE SEB
-   CLOSED: [2011-10-26 Wed 15:36]
-the SEB site does something funny so I can't insert text in
-fields. aparently document.activeElement.value doesn't work with framesets.
-
-seems to work using the ugly javascript in 
-xwidget-webkit-activeelement-js
-
-** support downstreams
-http://aur.archlinux.org/packages.php?ID=53902
-http://gpo.zugaina.org/app-editors/emacs-xwidget/ChangeLog
-** DONE the proof of concept canvas code should be disabled by default.
-   CLOSED: [2011-10-12 Wed 23:03]
-** TODO advi
-active dvi viewer. investigate if it could be xwidgetified.
-advi supports embedding inside presentations.
-** cairo configuration support
-gtk3 brings in cairo on Fedora, but apparently not on all plattforms.
-pkg-config --cflags cairo
-** TODO splint
-splint   -Demacs -DHAVE_CONFIG_H  -I. 
-I/home/joakim/build_myprojs/emacsnew/emacs.bzr/xwidget.mint/src -I../lib 
-I/home/joakim/build_myprojs/emacsnew/emacs.bzr/xwidget.mint/src/../lib   
-DGSEAL_ENABLE  -I/usr/include/gtk-3.0 -I/usr/include/atk-1.0 
-I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pango-1.0 
-I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -I/usr/include/pixman-1 
-I/usr/include/freetype2 -I/usr/include/libpng12   -I/usr/include/freetype2    
-I/usr/incl [...]
-
-** TODO 32 bit bug
-user reports that xwidgets segfaults  on the 32 bit Mint distribution
-but not the 64 bit. Mint is an Ubuntu derivative. I got some
-VirtualBox images to test with.
-** DONE youtube 
-   CLOSED: [2011-11-01 Tue 11:19]
-http://www.youtube.com/watch?v=DZdUgjEx_dQ&html5=1
-html5 makes it work without stupid flash plugins!
-** TODO clicking on an webkit xwidgets
-doesn't make the window active. this leads to problems.
-** DONE "g" should default to current url
-   CLOSED: [2011-11-03 Thu 22:25]
-"g" runs xwidget-webkit-browse-url which gets its interactive argument
-from browse-url-interactive-arg. this might need a new optional argument.
-
-http://test
-** TODO anything/helm support
-hook so anything/helm can filter browser history.
-** TODO new relative url code sometimes fail
-http://www.dilbert.com
-** TODO input field enhancements
-*** password field. 
-was straightforward
-
-*** textarea 
-less straightforward. I would like it to work like emacs-w3m, where a
-new editing buffer is opened. on c-c, the buffer is closed and the
-browser field updated. however, it's not immediately obvious how to
-store the reference to the field reliably.
-
-furthermore the current code doesn't seem to propagate linefeed
-properly to text areas.
-
-** DONE bug in current navigation handler
-   CLOSED: [2011-11-09 Wed 10:04]
-on www.dn.se
-Debugger entered--Lisp error: (args-out-of-range 
"http://platform.twitter.com/widgets/hub.html"; 54 357)
-  match-string(1 "http://platform.twitter.com/widgets/hub.html";)
-  xwidget-webkit-callback(48890368 navigation-policy-decision-requested)
-  xwidget-event-handler()
-  call-interactively(xwidget-event-handler nil nil)
-** TODO how to set the name of a webkit buffer?
-not obvious because, the buffer isn't created immediately and there is
-a callback that sets the buffer name automatically
-** TODO how to find next field in tab order?
-** TODO unique buffer names
-the webkit xwidgets renames the buffer after load but not uniquely so
-it sometimes fails.
-** TODO kill the offscreen webkit xwidgets when last view killed
-The offscreen xwidgets is currently kept around even if the xwidgets
-views are all gone. this is a general problem and it requires actions
-on the behalf of the application to resolve.
-
-In the case of webkit it is currently possible to get errors like these:
-
-Debugger entered--Lisp error: (error "Selecting deleted buffer")
-  xwidget-webkit-callback(60925380 navigation-policy-decision-requested)
-  xwidget-event-handler()
-  call-interactively(xwidget-event-handler nil nil)
-
-
-because the last view is gone and the offscreen widgets is still
-generating events. 
-
-In the case of webkit it is okay to kill the offscreen widgets
-completely when the user kills the last view window because it would
-be unexpected by the user to see it pop up again. This is not true in
-the general case.
-
-** DONE xwidgets debugging log
-   CLOSED: [2012-01-23 Mon 14:32]
-currently theres a lot of debugging traces using "message" which is
-annoying. Instead put them in a separate trace buffer.
-(see xwidgetbuffer)
-** TODO make garbage collect work for xwidgets
-when an xwidget is removed from xwidget-alist, and there are no other
-references(mostly views) the xwidget should be garbage collected.
-
-special finalization would go into gc_sweep()
-** TODO embedding evince
-http://developer.gnome.org/libevview/3.2/libevview-ev-view.html
-would be useful for reading PDF:s and other document types.
-it would work the same way webkit embedding works.
-
-** TODO support gobject introspection
-https://live.gnome.org/GObjectIntrospection/
-supporting gobject introspection would mean that more gtk widgets
-could be tried out with less effort, and also that the build process
-and runtime support would be easier. The drawbacks are small: somewhat
-slower execution, and difficulty in providing elisp bindings for
-introspection. 
-
-https://live.gnome.org/GObjectIntrospection/HowToWriteALanguageBinding
-
-http://developer.gnome.org/gi/unstable/gi-girepository.html
-http://developer.gnome.org/gi/unstable/gi-overview.html
-
-
-In order for GIR to work, it needs the namespace and class of a
-  widget. This is used to access the typelib file, which contains the
-  introspection data. The namespace and class is stored as a property
-  on the lisp symbol handle used by xwidgets to identify the widget
-  class.
-
-This snippet sets the needed :xwgir-class property, and calls the
-set_zoom_level method:
-
-M-x xwidget-webkit-browse-url RET www.emacswiki.org RET
-
-Then eval the following:
-
-;;load the webkit typelib
-(xwgir-require-namespace "WebKit" "2.0")
-
-;;provide the metadata needed so xwgir can work with the webkit-osr xwidget
-(put 'webkit-osr :xwgir-class '("WebKit" "WebView"))
-;;call the method
-(xwgir-call-method (xwidget-at 1) "set_zoom_level" '(3.0))
-
-It's also possible to create widgets dynamically, by using
-introspection to call a widget constructor(from xwidget-test.el):
-
-
-(defun xwgir-test ()
-  (interactive)
-  (xwgir-require-namespace "Gtk" "3.0")
-  (put 'color-selection :xwgir-class '("Gtk" "ColorSelection"))
-  
-  (xwgir-demo-a-xwgir-button)
-  (xwgir-call-method (xwidget-at 1) "set_label" '( "xwgir set label!"))
-  )
-
-Current limitation:
-- Only 0 arg constructors are supported at the moment. Since xwidgets
-  defer construction, the args needs to be stored with the xwidget.
-
-- xwgir-call-method does indeed lisp to gobject conversion for the
-  arguments, but only some primitive types are supported atm.
-
-- next to no argument checking. If wrong type args are used with the
-  xwgir methods, emacs crashes.
-
-*** TODO xwgir create components with more advanced constructor
-so this opens up an entire new can of beans.
-
-explain by example:
-lets say we want to create agtkhscale on screen. its a slider.
-https://developer.gnome.org/gtk3/stable/GtkHScale.html
-we can already create buttons, so sliders shouldnt be much more
-advanced right? wrong.
-
-the simplest slider constructor looks like:
-GtkWidget *         gtk_hscale_new
-(GtkAdjustment *adjustment);
-
-so in order to call it, we must be able to forward arguments to the
-constructor. this is almost already done, but we lack the ability to
-pass object instances, only simple types atm.
-
-we need to be able to create GtkAdjustment 
-https://developer.gnome.org/gtk3/stable/GtkAdjustment.html
-
-this we can already almost do, because an xwidget is a gir object
-with some decorations. we also store the decorated gir object in an
-array, retrievable from lisp.
-
-In order for this to be usable in practice, we need some changes:
-- lightweight objects should be stored un-decorated. they have no
-  need for the entire graphical machinery of xwidgets
-- lightweight objects should be garbage collectable, but this is the
-  same for all the xwidget objects, and isnt really resolved atm.
-
-
-** DONE investigate gdk_offscreen_window_set_embedder()
-   CLOSED: [2013-04-06 Sat 10:45]
-https://developer.gnome.org/gdk/unstable/gdk-Windows.html
-
-,----
-| Offscreen windows are more general than composited windows, since they
-| allow not only to modify the rendering of the child window onto its
-| parent, but also to apply coordinate transformations.
-| 
-| To integrate an offscreen window into a window hierarchy, one has to
-| call gdk_offscreen_window_set_embedder() and handle a number of
-| signals. The "pick-embedded-child" signal on the embedder window is
-| used to select an offscreen child at given coordinates, and the
-| "to-embedder" and "from-embedder" signals on the offscreen window are
-| used to translate coordinates between the embedder and the offscreen
-| window.
-| 
-| For rendering an offscreen window onto its embedder, the contents of
-| the offscreen window are available as a pixmap, via
-| gdk_offscreen_window_get_pixmap().
-`----
-
-okay, [2013-04-03 Wed] I finally suceeded in this approach!
-it was pretty  hard to make it work and currently works like this:
-- the on screen dravwing area is the embedder
-- you must implement "pick child"
-event forwarding is done automatically! 
-
-BUT its not really super, because it only works well with a single
-embedder.
-
-perhaps the strategy could be refined:
-- the window frame would be the embedder for all xwidgets. (but what
-  about several frames then?)
-- in the from-embedder signal handler, which maps container coords to
-  embedded widget coords, find out which xw-view i clicked on, and
-  compute the coords.
-
-[2013-04-04 Thu] I had a strategy working for a xwgir button but not
-a webkit. set_embedded in the motion event handler for the xv. it
-even works for 2 frames! but not webkit :(
-
-[2013-04-05 Fri] it works for xwgir osr components, but not for
-webkit. Webkit retains the previous event forwarding system.
-
-Now it works like this:
-- the offscreen widget is created as before
-- the on-screen views also as before, painting and copying as before.
-- gdk_offscreen_window_set_embedder() is now used to embedd the
-  offscreen widget in the onscreen one, upon view creation
-- only one widget can embedd one other. This means that the embedding
-  widget must be switched between the onscreen ones. This is now done
-  in the mouse motion event handler.
-
-The above approach has been tested for xwgir created buttons and seems
-to work. it doesnt work for webkit, so the old scheme is preserved
-for webkit.
-** TODO investigate git-remote-bzr
+Please see https://github.com/jave/xwidget-aux for documentation.



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