Changes
                                       
Yadex 1.5.2 (2001-06-30)

     * Platform: Compiles with GCC 3.0 (added std:: qualifiers where they
       were missing and removed #ifdef inside printf()).
       
Yadex 1.5.1 (2000-12-12)

     * Platform: One-line fix in menu.cc to please GCC 2.96 (of Red Hat 7
       fame). Thanks to Zebediah C. McClure for reporting the problem.
       
Yadex 1.5.0 (2000-08-27)

     * Build: Changed the way the diffs are generated after reading more
       carefully the patch(1) man page and learning the hard way that
       it's a very bad idea to put absolute paths in patches.
     * Build: Made it easier to add or remove individual options in
       CFLAGS and friends.
     * Command-line: New option -b to benchmark parts of Yadex. For
       hackers only.
     * Command-line: Removed option -e in prevision of reuse for another
       function.
     * Doc: Completed ygd.html.
     * Doc: Documented the usage of the LINES and YADEX_DIR environment
       variables.
     * Editing: Things that have an illegal angle are now shown with the
       angle Doom would see, instead of just a dot in the middle. The
       emulation is believed to be accurate for angles comprised between
       0 and 359. Values outside that range have not been tested.
     * Editing: Things flags and linedefs flags now grouped by 4 for
       readability. For linedefs, the decimal value of the flags field is
       not shown anymore.
     * Editing: In the object info box, the type and description of the
       current thing are now display in red if the type is invalid (i.e.
       not defined in the .ygd).
     * Editing: The things and linedefs flags operations ([a], [b], [c])
       now set MadeChanges as they should have from the start.
     * Editing: The View menu now contains entries for "Show object
       numbers" [&] and "Show grid" [h].
     * Editing: The Edit menu now contains entries for "Snap to grid" [y]
       and "Loc grid step" [z].
     * Editing: Rearranged the sidedef object info windows so that the
       textures are listed in a more intuitive order (upper, middle,
       lower instead of middle, upper, lower). Made labels shorter in
       preparation of the hypothetical inclusion of texture swatches in
       the future.
     * Editing: Fixed long-standing buglet with the sidedef info saying
       there are missing upper/lower textures even though both sectors
       have a "sky" ceiling/floor.
     * Editing: Implemented showing object numbers for linedefs and
       sectors. The placement of sector numbers is naive and inadequate
       for sectors that don't have a simple convex shape, but it's still
       better than nothing. Picked a somewhat brighter colour for object
       numbers.
     * Editing: Linedef object info box: if the first sidedef is missing,
       the message "(no first sidedef)" is printed in red instead of dim
       gray. Same thing for the second sidedef if the "2" flag is set.
     * Editing: Removed careless dereferencing of SideDefs[] for bad
       sidedef numbers in the sector selection code. I don't think this
       is what caused the mysterious unreproducible segfault James
       Caldwell reported, though. Made the object deletion function
       paranoid (checks that the objects to delete actually exist).
     * Editing: When found superimposed linedefs after merging vertices,
       the dialog box that asks whether they should be merged now
       mentions the numbers of the first two superimposed linedefs found
       instead of a laconic "Some linedefs are superimposed".
     * Editing: Zooming: the zoom factor is now displayed in percent,
       100% being 1/1.
     * Editing: Zooming: the zoom factors are now regularly spaced, with
       a ratio of 1.414 between them. This removes the annoying "jump"
       between the zoom factors greater than 1/2. It also fixes the
       oddities that happened when zooming in after [`]. The ratio
       between zoom factors can be controlled through the new parameter
       "zoom_step".
     * Editing: Zooming: the "zoom" parameter has been replaced by the
       new parameter "zoom_default". The latter is expressed in percent,
       not in 1/n units. It's now possible to specify an initial zoom
       factor of more than 1/1. When opening a new window, Yadex now
       adjusts the zoom factor so that the level fills the window. Should
       you want to revert to the old behaviour, you can do it by setting
       zoom_default to 12.
     * Editing: ['] and [`] now go to the current centre of the level
       (they used to go to where the centre was when the level was opened
       or created).
     * Editing: [`] now has a menu item (View -> Whole level).
     * Editing: The grid has changed. There are now dots every step map
       units, dim lines every 4×step units, normal lines every 16×step
       units and bold lines every 64×step units. The new grid is supposed
       to be less obtrusive visually, faster to display and more distinct
       when scrolling.
     * Editing: New function to swap floor and ceiling flats of selected
       sectors (Misc. operations -> Swap flats).
     * Editing: When not in things mode, things are drawn in a dimmer
       shade of gray and do not hide the linedefs anymore.
     * Game/wad: Removed the "-g wolf" bit. [For those who still haven't
       got it : the support for Wolfenstein 3D announced in the CHANGES
       for version 1.4.0 was of course a hoax, 1.4.0 having been released
       on April 1st.] Hope you've been having as much fun as I have. :-)
     * Game/wad: Heretic: made the golem leader ghost, undead warrior
       ghost and golem ghost look a little more ghostly. Made the
       gargoyle leader, golem leader and golem leader ghost look
       different from their vanilla counterparts by using sprites IMPXD
       and MUMMY. Assigned a sprite to things 31 and 32 (enchanted
       shield, SHD2 and mystic urn, SPHL).
     * Game/wad: Heretic: corrected things radii in heretic.ygd, using
       [1]info2ygd and the Heretic source as a reference. Almost all
       radii were wrong, a few grossly so (maulotaur, ironlich and
       gargoyle).
     * Game/wad: Strife: many new things and linedef types thanks to
       [2]Matt Miller.
     * Game/wad: Doom alpha 0.4: definitions for thing types 2020, 2036,
       2038 and 2046.
     * Game/wad: Updated format comments in *.ygd.
     * Game/wad: Sprites in pwads now supported (between S_START/S_END or
       SS_START/SS_END or SS_START/S_END). This fixes Yadex's failure to
       show redefined sprites in [3]alitcsf.wad, [4]basilica.wad and
       [5]strifed1.wad. A few Aliens TC sprites don't work yet but it's
       for a different reason (DEH).
     * Game/wad: Sprites now shown on the map when in things mode. You
       can switch between sprites and squares with View -> Show sprites
       [%]. New config file parameter "sprite_scale" to adjust the scale
       at which sprites are displayed (default 100%).
     * Game/wad: The right sprite is shown, even if the sprites are not
       in alphabetical order in the wad (cf BARWA0 in Strife).
     * Game/wad: The function to add pwads (be it from the command line
       or with the "r" command) has been heavily reworked. It's more
       robust and handles errors better. It does not leak file handles
       anymore when you add the same pwad more than once. It also accepts
       to add iwads, modulo a warning (though you should expect problems
       later if you do that). The merging of the pwad directory into the
       master directory is still lousy.
     * Game/wad: Fixed duplicate entries in the flat selector. This bug
       was found by "Ras2". It happened whenever you added the same flat
       thrice or more.
     * Game/wad: EDGE: added definitions for EDGE linedef types and
       things types to doom.ygd and doom2.ygd. Thanks to [6]Andrew Apted
       for providing the ygd data.
     * Game/wad: EDGE: in sector mode, show information for EDGE
       extrafloors if there are any.
     * Misc: A couple of calls to fatal_error() were turned into calls to
       report_error() (don't abort).
     * Misc: New game definition file directive "sky_flat" to specify the
       name of the "sky" flat. Replaced all occurrences of F_SKY1 by
       references to this parameter. Fixes Check -> Check for missing
       textures for Hexen and Strife. Bumped game definition file
       version# to 4.
     * Misc: Because it seems to disturb people (and for the pleasure of
       proving Matt wrong), I've made the texture selector clip textures
       to size. Since there's no scrolling/zooming system yet, I also
       enlarged the viewing area from 256×128 to 512×256 to alleviate the
       lossage on large textures.
     * Misc: Removed the "Press Shift-F1 to save image to file" text in
       the selector. It's been a no-op ever since 1.0, anyway.
     * Misc: In the selectors, pressing [F1] prints the location of the
       current item to stdout (file name and offset). Works with flats,
       patches and sprites but not textures. It's there to help trace
       Ras' bug.
     * Misc: Made LoadPicture() nicer and safer. It gracefully bails out
       if there are more than 20 errors on a single picture. It does not
       make Yadex abort anymore on read errors in the header or column
       offset table. I've done this by modifying wad_read_i16() and
       wad_read_i32() so other functions might have been impacted.
     * Misc: Config file: commented out most settings (this has no
       visible effect since those settings were just reiterations of the
       default values built into the executable). Also changed the
       initialization code so that Yadex can run without a config file.
     * Misc: Config file: unknown variables are ignored with a warning
       instead of triggering a fatal error. The intent is to facilitate
       sharing config files between versions.
     * Misc: Config file: bumped version# to 3.
     * Misc: Made Yadex use YADEX_GAME as documented and not Y_GAME.
       Oops !
     * Misc: New feature in the flat/picture/sprite selector to show
       where the current image comes from (file name and file offset).
       For debugging.
     * Misc: The window size (width/height and -w/-h) can now be
       expressed in percent of the screen size, by appending a "%" to the
       value. The default size, instead of being 640×480 in the
       executable and 900×600 in the config file is now 90%×90%. It's
       still possible to give absolute width and heights, of course.
     * Misc: No tantrum thrown if the game definition file contains no
       thing directive.
     * Misc: Removed the check for sector headroom being < 1024 in Checks
       -> Check for missing textures. It was sometimes annoying and
       inaccurate anyway.
     * Platform: Images display correctly on packed 24-bit X servers
       (i.e. bits_per_pixel actually is 24 and not 32). The scanline_pad
       member of the ScreenFormat structure is now honoured (not that
       XFree86 seemed to mind much when it wasn't).
     * Platform: Began to clean the code up to make porting less
       difficult.
     * Platform: Added patch to get Yadex to compile with GCC 2.7
       (patch/gcc-2.7.diff). GCC 2.7 is officially considered
       unsupported, though. You're on your own.
       
Yadex 1.4.0 (2000-04-01)

     * Command-line: The parsing of the command line arguments is now
       case-sensitive. Yes, that's right, it used to be case-insensitive.
       I never knew. I just realized it by accident. DOS is not dead.
     * Doc: The man page now has an "OPTIONS" section.
     * Doc: Three new makefile targets, man, dvi and ps, for people who
       hack the doc.
     * Editing: Made object numbers slightly more legible in crowded
       areas.
     * Game/wad: Added support for Wolfenstein 3D (-g wolf).
     * Misc: The code that parses the configuration file is smarter and
       its error messages are more informative. Doesn't choke anymore on
       a line containing just spaces or on comments not starting on
       column 1. Thanks to "Ras2" for reporting the bug.
     * Misc: New commands "viewtex" and "viewflat" so that you can browse
       textures and flats without having to open a level. This is
       primarily useful to me, for testing purposes.
     * Misc: More sanitization : the parsing of the configuration file is
       now case-sensitive when matching option names and values
       ("yes"/"no", "true"/"false", "on"/"off").
     * Misc: The flat/patch/sprite/texture viewer does not flicker
       anymore, and is somewhat faster when viewing textures. The list of
       names in the flat viewer has grown from 3 to 5 lines.
     * Misc: The diffs are now in unified format (supposedly just as good
       and IMHO clearer).
       
Yadex 1.3.2 (2000-01-14)

     * Build: Oops ! I had forgotten to set CC and CXX back to their
       "sane" values before cutting the 1.3.1 tarball.
     * Code: "make dist" now also generates a diff.
       
Yadex 1.3.1 (2000-01-12)

     * Build: Fix for "Ras2"'s compile error with g++ 2.7.2.3 :
  c++ src/disppic.cc
  In file included from /usr/include/g++-2.7/defalloc.h:24,
                   from /usr/include/g++-2.7/map.h:21,
                   from /usr/include/g++-2.7/map:6,
                   from src/patchdir.h:35,
                   from src/disppic.cc:33:
  /usr/include/g++-2.7/algobase.h:47: macro `min' used with too many (3) args
  /usr/include/g++-2.7/algobase.h:57: macro `max' used with too many (3) args
  make: *** [obj/0/disppic.o] Error 1
     * Build: Fix for HAVE_NANOSLEEP being always false. Thanks to "Ras2"
       for pointing it out.
       
Yadex 1.3.0 (2000-01-11)

     * Build: The makefile now honours the dependencies in yadex.dep.
     * Build: Support for FHS-compliant systems: "make install" now
       copies the man pages into /usr/local/share/man/man6/ if
       /usr/local/share/man/ exists. If not, it still uses
       /usr/local/man/man6/ (requested by Joseph Carter).
     * Build: Added "#include <stddef.h>" to fix compilation error on
       wads.cc under Solaris.
     * Build: Downgraded the makefile and scripts to use the old
       backquote syntax for command substitution, because Oliver Kraus'
       reports suggest that the Solaris sh does not understand the "$()"
       syntax. Barfulation !
     * Build: New makefile target showconf that shows the value of all
       the important macros as well as the output of certain commands. If
       you have trouble compiling Yadex, mail me the output of "make
       showconf".
     * Build: A bunch of little changes in the makefile to try to make
       build problems on Solaris go away.
     * Doc: Fixed several discrepancies in README.
     * Game/wad: Support for the german edition of Doom II (as the iwad
       has no MAP31 and MAP32, Yadex 1.1.0 and 1.2.0 used to say "this is
       the shareware version of the game").
     * Game/wad: Replacement patches in pwads are now supported, even if
       between PP_START and PP_END. Fixes failure to see redefined
       textures with mbfedit!.wad, alitcwad.wad and certainly many
       others. Replacement patches in pwads not between P_START/P_END or
       PP_START/PP_END are not recognized anymore. Many PNAMES errors
       that would have made previous versions of Yadex abort now just
       make it print warnings.
     * Misc: Cleaned up the web page source and makefile. Added
       documentation, should someone else take over maintainership. No
       harm in dreaming.
     * Misc: New command viewpat to browse through the patches.
     * Misc: It's now possible to have several different versions of
       Yadex installed simultaneously. Some paths have changed :
          + $(PREFIX)/share/games/ is now
            $(PREFIX)/share/games/yadex/$(VERSION)/
          + $(PREFIX)/etc/yadex.cfg is now
            $(PREFIX)/etc/yadex/$(VERSION)/yadex.cfg
          + ~/yadex.cfg is now ~/.yadex/$(VERSION)/yadex.cfg
          + $(PREFIX)/bin/yadex changed to $(PREFIX)/bin/yadex-$(VERSION)
          + $(PREFIX)/bin/ybsp changed to $(PREFIX)/bin/ybsp-$(VERSION)
          + $(PREFIX)/bin/yadex is now a symlink pointing to
            yadex-$(VERSION)
          + $(PREFIX)/bin/ybsp is now a symlink pointing to
            ybsp-$(VERSION)
       The insertion of a yadex/ component in the paths was done for two
       reasons. In the first place, it was requested by Joseph Carter for
       game definition files, to reduce clutter in
       $(PREFIX)/share/games/. I extended it to configuration files
       because it I thought it was a nice way not to clutter
       $(PREFIX)/etc/. On the other hand, it was not done for man pages
       and executables because it would have interfered.
     * Misc: Fixed bug where if you typed "yadex: c level", then created
       or edited a level and then closed the editing window, you got a
       dozen of messages like this one : "Warning: error freeing colour
       00005820h (BadAccess (attempt to access private resource
       denied))". I hope this fixes the related item in TODO.
       
Yadex 1.2.0 (1999-11-23)

     * BSP: Added missing newline in banner.
     * BSP: Silenced GCC 2.95.2 warnings about implicit braces.
     * Build: The makefile doesn't rebuild doc/ every time a source file
       is changed anymore.
     * Build: Can now be built on machines where Perl is not installed.
     * Build: The doc can now be built on machines with a non-GNU find.
     * Build: Fixed compilation errors with GCC 2.95.2 in src/infobar.cc.
     * Build: Silenced most GCC warnings.
     * Code: Fixed a typo in the legal notices at the beginning of the
       source files.
     * Doc: HISTORY renamed as CHANGES, since that seems to be a more
       widespread convention.
     * Editing: The checks don't beep for every error anymore, just the
       first one.
     * Editing: Object info window: the sprite and flats graphics don't
       flicker anymore when the pointer moves from one object to another.
       Besides, if the sprite is not found, displays the message
       "sprite_name not found" instead of just a blank area.
     * Game/wad: Doom alpha & press release versions: it's now possible
       to save levels. Note: they're saved to regular Doom format, not
       Doom alpha format.
     * Game/wad: Doom II: The boss shooter thing now has a sprite
       (BOSFB0).
     * Game/wad: Hacx and Aliens TC: fixed a bug that made Yadex segfault
       when trying to edit a Hacx level (or alitcsf.wad from
       alntc19{a,b}.zip).
     * Game/wad: For homogeneity with DeuTex, less confusion and to
       reduce the risk of conflicts with other applications, the game
       names for Doom alpha 0.2, Doom alpha 0.4, and Doom alpha 0.5 are
       now "doom02", "doom04" and "doom05" respectively instead of
       "alpha02", "alpha04" and "alpha05". It follows that some
       command-line options have changed :
          + "-g alpha02" is now "-g doom02",
          + "-g alpha04" is now "-g doom04",
          + "-g alpha05" is now "-g doom05".
       Configuration file directives :
          + "game = alpha02" is now "game = doom02",
          + "game = alpha04" is now "game = doom04",
          + "game = alpha05" is now "game = doom05".
       Paths :
          + /usr/local/share/games/alpha02/ is now
            /usr/local/share/games/doom02/,
          + /usr/local/share/games/alpha04/ is now
            /usr/local/share/games/doom04/,
          + /usr/local/share/games/alpha05/ is now
            /usr/local/share/games/doom05/,
          + /usr/local/share/games/alpha02.ygd is now
            /usr/local/share/games/doom02.ygd,
          + /usr/local/share/games/alpha04.ygd is now
            /usr/local/share/games/doom04.ygd,
          + /usr/local/share/games/alpha05.ygd is now
            /usr/local/share/games/doom05.ygd.
     * Game/wad: Fixed Yadex aborting when trying to view textures for
       versions of Strife >= 1.1. The problem was that Strife 1.1 and
       above use a different format for the TEXTURE1 and TEXTURE2 lumps
       (Strife 1.0 uses the same format as Doom). New game definition
       file directive "texture_format strife11" to support that format.
       strife.ygd now contains "texture_format strife11". Added
       strife10.ygd that is identical to strife.ygd except that it
       contains "texture_format normal". Summary :
          + if you have the Strife 1.0 iwad, use "-g strife10" or "game =
            strife10",
          + if you have Strife 1.1 or above, use "-g strife" or "game =
            strife".
       Thanks to Kim Parrott for reporting the bug and Len Pitre for
       pointing me in the right direction.
     * Misc: The "dump" command now prints correctly the last line even
       if the length of the lump is not a multiple of 16.
     * Misc: For homogeneity with DeuTex, the following game definition
       file directives have changed :
          + "texture_format alpha04" is now "texture_format nameless",
          + "texture_lump texture1" is now "texture_lump normal",
          + new choice "texture_lump none".
     * Misc: For homogeneity with DeuTex, automatic texture names for
       Doom alpha 0.4 are now "TEXnnnn" where nnnn is zero-based.
     * Misc: Bumped game definition file version# to 3.
     * Misc: When trying to use a pwad as iwad, emit a warning instead of
       seeing this as a fatal error.
     * Misc: Added a palette viewer (PLAYPAL and COLORMAP). Can be run
       from the prompt with the viewpal command or from the level editing
       window with [Ctrl][P].
     * Misc: The sometimes tedious pwad loading messages are not
       displayed anymore, unless in verbose mode. By default, Yadex now
       just prints which levels the pwad contains.
       
Yadex 1.1.0 (1999-08-22)

     * BSP: Included Colin Phipps' [7]fix for the bugs in
       [8]bsp23bug.zip.
     * BSP: Renamed the executable and the man page as ybsp, to avoid
       having Yadex and Xwadtools overwrite each other's BSP.
     * BSP: The whirling baton is now disabled if stderr is not a TTY.
       This is the same thing Udo Munk did for [9]Xwadtools' BSP with the
       -noprog option except that here it's automatic.
     * BSP: Made the man page spell out exactly which version of BSP this
       is.
     * BSP: Inserted notice in the banner that this is the version that
       comes with Yadex. In the online help, replaced "TMP.WAD" by the
       correct "tmp.wad".
     * Building: Fixed compilation error on line 44 of bitvec.h.
     * Code: Removed CR characters that remained in some of the source
       files.
     * Code: New function DrawScreenString(). Began to use it instead of
       DrawScreenText(). This should squash some latent bugs, for example
       regarding flat and texture names containing percent signs (%).
     * Code: Fixed constness warnings in cfgfile.cc.
     * Code: Replaced most occurrences of hard-coded 8 by one of
       WAD_NAME, WAD_FLAT_NAME, WAD_PIC_NAME and WAD_TEX_NAME.
     * Code: New directives level_format and level_name in the YGD files.
       As a result, been able to remove most tests on specific values of
       the game parameter.
     * Doc: Too many changes and additions to list. Since the last
       release, the HTML doc has doubled in size (from 80 kB to 160 kB).
       Added a dozen of screenshots.
     * Doc: In an attempt to make it easier to find what you're looking
       for, I've split the doc in a larger number of files, referred to
       by a top level index.html.
     * Doc: Moved the HTML doc and the man pages to the doc/ directory,
       so as not to clutter the base directory too much.
     * Doc: Man pages: the first argument of the .TH macro (the name) is
       now all caps since that's what (almost) everybody else does.
     * Editing: Autoscroll is now off by default -- use "autoscroll =
       true" in yadex.cfg if you want it back.
     * Editing: New bindings [e] and [Ctrl][e] to select all linedefs
       that belong to the same non-forked path.
     * Editing: New bindings [E] and [Ctrl][Shift][e] to select all
       single-sided linedefs that belong to the same non-forked path.
     * Editing: New functions to flip and mirror linedefs, sectors,
       things and vertices.
     * Editing: Fixed the "string art" bug. That was a subtle bug that
       happened only as a result of a rare chain of events. The recipe to
       it is to render a vertex unused (for example by deleting all the
       linedefs that use it), save the level, make a change that does not
       call for a rebuilding of the nodes (for example, moving a thing or
       changing an attribute of a sector), save the level, quit and load
       again. At that point, a nice surprise awaits you: the linedefs are
       all entangled (hence the name). Spectacular, and even beautiful,
       but also very annoying if you don't have a backup copy of your
       level.
       This is the same bug I thought I had fixed in Yadex 1.0.0_alpha3.
       In fact, I had cut one of the paths that led to it but the bug
       itself was still there. It reappeared in february 1999.
     * Editing: Fixed an old DEU bug where you sometimes couldn't select
       a newly created sector to the west of the level until you saved.
     * Editing: It's now possible to toggle linedef flags 8-15 and to
       specify linedef flags field values greater than 511.
     * Editing: It's now possible to set/clear/toggle things flags 7-15.
     * Editing: Made the Not-enough-player-starts and
       Not-enough-deathmatch-start dialogs on saving more intuitive (it
       was about time).
     * Editing: New function "Exchange objects numbers".
     * Editing: Things types are now displayed in decimal, not in
       hexadecimal. Other minor cosmetic changes.
     * Editing: The focus-on-object function now works much better. It
       does not land off-target or zoom in excessively anymore.
       Superimposed things and sectors containing other sectors or not
       containing their own centre don't confuse it anymore. It's still
       fooled by unclosed sectors, though.
     * Editing: Changed the meaning of [q]. It used to save and quit. Now
       it just quits (same thing as [Esc]).
     * Editing: The edit command can now edit levels of any name. If you
       had a wad with a level named "FOO" in it, you could edit that
       level by typing "edit foo". In case you're wondering, no there's
       no practical application to this (beyond experimenting).
     * Editing: Reminder to build nodes: the message is now more
       specific.
     * Editing: Command mode: typing ^D at the prompt now works.
     * Editing: Insert linedef and split sector: the new linedef now goes
       from the first selected vertex to the second and not the other way
       around.
     * Editing: Insert linedef and split sector: does not loop forever
       anymore if there are forks in the edge of the sector (for example
       like when trying to split between vertices 283 and 278 of MAP01 of
       Doom II).
     * Editing: [n], [p], [>] and [<] now move the view so that the
       object to highlight is under the pointer.
     * Editing: The messages displayed when loading pwads are more
       compact (several lumps are printed on the same line and groups of
       sprites are collapsed). The end marker for groups of flats,
       patches and sprites is now printed.
     * Editing: Flat/sprite/texture viewer : added bindings [Ctrl][u] and
       [Ctrl][w] to erase to start of line, [Ctrl][f] and [Ctrl][v] to
       page down and [Ctrl][b] to page up.
     * Editing: Flat/sprite/texture viewer : added bindings [Ctrl][PgUp]
       and [Ctrl][PgDn] to move to top and bottom of list, because [Home]
       and [End] will eventually cease to be available for that (they
       will be bound to SOL and EOL).
     * Editing: Flat/sprite/texture viewer : made [Up] and [Down] work
       even when there are duplicate names.
     * Editing: Flat/sprite/texture viewer : InputNameFromListWithFunc()
       is now genuinely case insensitive. The positioning in the list of
       names is now correct, even if the name given is lower-case.
     * Editing: Flat/sprite/texture viewer : reduced flickering (still
       room for improvement, though).
     * Editing: Flat/sprite/texture viewer : the current name was way too
       dim if not in the list. Fixed.
     * Editing: Flat/sprite/texture viewer : made image window 320x200
       instead of 256x128.
     * Editing: Sprite viewer : new bindings [Ctrl][n] and [Ctrl][p] to
       go to start of next/previous group of sprites.
     * Editing: Sprite viewer : fixed display bug.
     * Editing: Spectres now look more like spectres.
     * Editing: Confirm-or-cancel dialogs: more intuitive. You can now
       confirm with [y] or [Return] and cancel with [n] or [Esc]. All
       other keys are ignored (previously, [y] confirmed and all other
       keys cancelled). Expose events are now handled (previously they
       were ignored).
     * Editing: Some abnormal conditions that used to trigger fatal
       errors now just cause a message error to be printed. The current
       operation is aborted but not the whole program anymore.
     * Game/wad: Fixed segfault on levels containing a thing of type 0
       (like Eternal MAP25 and some Final Doom maps).
     * Game/wad: When reading a level from a wad, now verifies that the
       SECTORS, THINGS, VERTEXES, LINEDEFS and SIDEDEFS lumps have
       correct sizes and that sidedefs, sectors and vertices references
       are correct.
     * Game/wad: Final Doom : should be supported now. Yadex does not
       assume anymore that F1_START is always present, which caused it to
       segfault on either or both Final Doom iwads.
     * Game/wad: Heretic : added sprite names for 58 thing types.
     * Game/wad: Hexen : added very partial support (-g hexen). You can
       edit levels but not save them. Hexen-specific linedef and things
       fields are ignored, and so is the BEHAVIOR lump. Most definitions
       are missing.
     * Game/wad: Strife : added partial support (-g strife). Yadex now
       knows about the translucent linedef flag and the new sector types.
       Thanks to Len Pitre for the help. Still missing : the new things
       flags, most things types and linedefs types. Anybody wants to work
       on strife.ygd ?
     * Game/wad: MBF : supported. Yadex now knows about the friendly
       thing flag, thing type 888 (Dog) and linedef types 271 and 272
       (transfer sky texture).
     * Game/wad: Doom press release pre-beta : supported (-g doompr).
       Added support for the PR picture format and the definitions for
       things 2016 (evil sceptre) and 2017 (unholy bible).
     * Game/wad: Doom alpha : read-only support (-g
       alpha02|alpha04|alpha05). Added support for the alpha picture
       format, the TEXTURES lump, the different level format and the
       incompatible level names (E1M10 through E1M13).
     * Game/wad: Added support for FF_START/FF_END in addition of
       FF_START/F_END. As a result, Yadex does not barf anymore on
       basilica.wad (but issue a warning). F?_START is not supported
       anymore ; it has to be FF_START.
     * Game/wad: Made "Post too long. Wad file might be corrupt" a
       warning, not a fatal error anymore.
     * Game/wad: New directives picture_format, texture_format and
       texture_lump in the YGD files, to support Doom alpha and Doom PR.
     * Misc: New command make_palette_ppm to generate a raw PPM file
       containing all the colours of the palette.
     * Misc: Cosmetic changes in the prompt and character mode interface.
     * Misc: make_gimp_palette : the generated palette files now include
       RGB values in the comments.
     * Misc: Removed from the menus the functions that were not
       implemented (File->Print, Edit->Find, View->3D preview).
     * Misc: Failure to load the specified X font is not a fatal error
       anymore.
     * Misc: New command line options --help and --version.
     * Misc: Bumped game definition file version# to 2.
     * Platform: Removed dependency on nanosleep(), strcasecmp() and
       strncasecmp(). Thanks to Udo Munk for pointing out that
       nanosleep() is not always available.
     * Platform: Now compiles with other compilers than GCC/EGCS without
       modifying the makefile.
     * Platform: New parameter idle_sleep_ms to set the time in ms
       between polls of the X server when the input queue is empty.
     * Platform: Previously, if the CPU and the X server had different
       endiannesses and the screen depth was more than 8 bits, sprites,
       flats and textures were displayed with wrong colours. This is now
       fixed.
     * Platform: The build, group, insert and save commands should now
       work correctly on big-endian machines.
     * Platform: The bell has been resurrected on X.
     * Platform: Should now compile on X11R5 systems (to be verified).
       Thanks to Udo Munk for the fix.
       
Yadex 1.0.1 (1999-01-02)

     * Doc: New sections "Moving around" and "Other credits" in the
       user's guide.
     * Editing: Split linedefs and sector: new linedef now goes from 1 to
       2 and not the other way around.
     * Editing: Added scrolling with the arrow keys.
     * Editing: [Pgup], [Pgdn], [Home] and [End] now scroll one page at a
       time.
     * Editing: New variable autoscroll to disable autoscrolling.
     * Editing: New variables autoscroll_amp and autoscroll_edge to tweak
       autoscrolling.
     * Editing: New shortcut [x] to "Split linedef (insert new vertex)".
     * Editing: New shortcut [w] to "Split linedefs and sector".
     * Misc: Fixed segfault on trying to edit MAPnm in Doom/Heretic mode
       or EnMm in Doom II mode.
     * Misc: New prompt command make_gimp_palette to generate a gimp
       palette file from PLAYPAL.
     * Misc: Bumped configuration file version# to 2.
       
Yadex 1.0.0 (1998-12-26)

     * Code: Moved the source files to a subdirectory.
     * Doc: A few additions in the user's guide
     * Editing: Fixed buglet in positioning of newly copied objects.
     * Game/wad: Game support: added definitions for Boom's things 5001
       and 5002 (point pusher and puller).
     * Misc: Added reminder to build nodes after making changes.
     * Misc: Added magic string to configuration file.
     * Misc: Added magic string to game definition file.
       
Yadex 1.0.0_alpha3 (1998-12-23)

     * Doc: A few additions/corrections in the hacker's guide.
     * Editing: Fixed spectacular corruption of linedefs (string art bug)
       that occurred if all you did during a given session was deleting
       vertices.
       
Yadex 1.0.0_alpha2 (1998-12-22)

     * BSP: Included BSP 2.3 (thanks to Lee Killough).
     * Doc: Improved user's guide.
     * Editing: Added new commands [a], [b] and [c] to set, toggle and
       clear things and linedefs flags.
       
Yadex 1.0.0_alpha1 (1998-12-17)

     * Code: Removed dereferencing of NULL pointer in
       ParseCommandLineOptions() (DEU).
     * Code: Replaced occurrences of "x==TRUE" and "x==FALSE" by "x" and
       "!x".
     * Code: Replaced occurrences of "x=TRUE" and "x=FALSE" by "x=1" and
       "x=0".
     * Command-line: You don't have anymore to put "-file" or "-pwad" in
       front of pwads names on the command line. E.G. you can type "yadex
       foo.wad".
     * Command-line: Deleted a few little-used or DOS-specific options.
     * Editing: Menu bar and pop-up menus much improved.
     * Editing: Info bar reworked.
     * Editing: When prompted to "Press a key to continue", you can now
       also press the left mouse button.
     * Editing: Grid: the grid step can now adapt automatically as you
       zoom in/out.
     * Editing: Grid: whether dragging is snapped to grid is now
       independent of whether the grid is shown or not (added flags
       grid_snap and grid_shown).
     * Editing: Added finer-grained confirmation options.
     * Editing: General editing: you can now scroll the map further from
       the centre of the level.
     * Editing: Added ['] to re-centre the window around the centre of
       the map.
     * Editing: Added [`] to re-centre the window around the centre of
       the map and adjust the zoom so that the map fills the screen.
     * Editing: Added [&] to show things and vertices numbers.
     * Editing: Autoscroll: scroll speed is now progressive.
     * Editing: Autoscroll: easier to use near the top of the window.
     * Editing: [Left], [Right], [Up], [Down] do nothing.
     * Editing: [Space] does not toggle move fast/slow anymore; it
       toggles between nominal zoom and x 4.
     * Editing: Highlighting of things, vertices and linedefs much
       improved.
     * Editing: Dragging objects is now done with the left mouse button
       instead of the right button.
     * Editing: Editing object properties is now done by double-clicking
       on the object.
     * Editing: Selection and drag-and-drop have changed a lot.
     * Editing: Selection box: removed the -a option and the addselbox
       parameter. Whether the selection box is additive or not is now
       controlled dynamically by the user (with [Ctrl]).
     * Editing: Sprite viewer: sprites are now centred.
     * Editing: Linedef info: shortened flags names to one character.
     * Editing: Linedef info: a missing normal texture on a 1-sided
       linedef is now flagged in red.
     * Editing: Linedefs copy: you now have the choice between
       duplicating the sidedefs too and reusing the same sidedefs. DEU
       left the new linedefs sidedef-less and, so far, Yadex used to
       reuse the same sidedefs.
     * Editing: Linedefs: added function to "unlink" sidedefs.
     * Editing: Linedefs: dragging linedefs is much faster than before.
     * Editing: Sectors: in the object info window, added display of
       floor and ceiling height delta with respect to previous sector.
     * Editing: Sectors: in the object info window, added display of
       floor and ceiling texture.
     * Editing: Sectors: dragging sectors is much faster than before.
     * Editing: Things: now drawn as squares so that it's easier to see
       whether they are stuck in a wall or another thing. And you don't
       have to highlight them to see their angle. Note: the old shape is
       still available by defining ROUND_THINGS at compile-time.
     * Editing: Things: changed the colours again. Tried to make
       important things stand out and conversely. Bonuses are now dark
       green and player/ deathmatch starts bright green. Keys are
       magenta. Decoration is dim blue instead of white. Unknown objects
       are cyan instead of white. Weapons are orange instead of brownish.
       Heretic sound source things and Boom point pushers are dim
       turquoise-ish.
     * Editing: Things: the sprite is now shown in the object info
       window.
     * Editing: Vertices: deciding whether a vertex is on a linedef is
       now done on the distance in pixels, not in map units. So you can
       now work on very fine details (E.G. vertices only 2 map units
       away) provided that the zoom factor is high enough.
     * Editing: Fixed minor glitch in texture viewer that showed with
       BIGDOOR7, SKY1, TEKWALL1, TEKWALL5 and others (DEU).
     * Editing: When highlighting a sector, compared
       SideDefs[LineDef[n].sidedef1].sector with ObjNum even though
       .sector was -1. Somehow it always tested false (DEU).
     * Editing: "Check textures names": the name of the offending texture
       is now printed correctly even if it is 8 characters long (DEU).
     * Editing: "Check textures names": if you fixed a missing texture,
       the editor was not made aware that you had made changes to the
       level (DEU).
     * Editing: Unused sectors are not selected anymore (DEU).
     * Editing: Changing the preferences could overwrite other variables
       (DEU).
     * Editing: InputNameFromListWithFunc() used to segfault if you
       pressed [Pgdn] on a list shorter than (listdisp + 1) elements
       (DEU).
     * Editing: Removed segfault in AlignTexturesX() (DEU).
     * Game/wad: Heretic is now supported.
     * Game/wad: Added support for Boom's new thing flags
       not-in-deathmatch and not-in-coop.
     * Game/wad: Added support for Boom's new linedef flag pass-through.
     * Misc: Renamed as Yadex to avoid confusion with Yet Another Diagram
       Editor.
     * Misc: Loading pwads: implemented standard directories. If the pwad
       to load is in one of the standard directories (or a subdirectory)
       you don't have to type the whole name.
     * Misc: Loading pwads: added standard directories and made the
       messages less verbose for pwads that contain patches
       (PP_START/PP_END).
     * Misc: Removed segfault during fatal_error() on failure to open the
       iwad (DEU).
     * Misc: The prompt now groks TTYs with a number of lines other than
       25.
     * Misc: Changed the welcome message (a.k.a. "reminder").
     * Misc: Added an "About Yadex..." window.
     * Misc: Don't copy SEGS, SSECTORS, NODES, REJECT and BLOCKMAP from
       the original file anymore when the map has changed. Makes smaller
       wad files. Nice for archival.
     * Misc: Added environment variable YADEX_GAME.
     * Platform: Ported to X (plain Xlib). This version is not available
       for DOS.
     * Platform: Now works on big-endian machines.
     * Platform: Removed several DOS-isms from file name handling code.

References

   1. http://www.teaser.fr/~amajorel/info2ygd/
   2. http://my.ohio.voyager.net/~mattm/
   3. ftp://ftp.cdrom.com/pub/idgames/themes/aliens/alntc19a.zip
   4. ftp://ftp.cdrom.com/pub/idgames/levels/doom/a-c/basilica.zip
   5. ftp://ftp.cdrom.com/pub/idgames/levels/doom2/Ports/s-u/strifed1.zip
   6. http://www.netspace.net.au/~ajapted/
   7. http://lxdoom.linuxgames.com/notes.html#bsp
   8. http://www.teaser.fr/~amajorel/doom/bsp23bug.zip
   9. ftp://ftp.cdrom.com/pub/idgames/source/