This is a technique I've had on the todo list (and been using by hand)
for years: a domino can't be placed if it would divide the remaining
area of the grid into pieces containing an odd number of squares.
The findloop subsystem is already well set up for finding domino
placements that would divide the grid, and the new is_bridge query
function can now tell me the sizes of the area on each side of the
bridge, which makes it trivial to implement this deduction by simply
running findloop and iterating over the output array.
This technique borrows its name from the Solo / Map deduction in which
you find a path of vertices in your graph each of which has two
possible values, such that a choice for one end vertex of the chain
forces everything along it. In Dominosa, an approximate analogue is a
path of squares each of which has only two possible domino placements
remaining, and it has the extra-useful property that it's
bidirectional - once you've identified such a path, either all the odd
domino placements along it must be right, or all the even ones. So if
you can find an inconsistency in either set, you can rule out the
whole lot and settle on the other set.
Having done that basic analysis (which turns out to be surprisingly
easy with an edsf to help), there are multiple ways you can actually
rule out one of the same-parity chains. One is if the same domino
would have to appear twice in it; another is if the set of dominoes
that the chain would place would rule out all the choices for some
completely different square. There are probably others too, but those
are the ones I've implemented.
I've made the existing optional solver diagnostics appear as the
verbose output of the solver program. They're not particularly legible
at the moment, but they're better than nothing.
to it giving each game's "internal" name (as seen in the source file,
.R etc) and also a brief description of the game. The idea of the
latter is that it should be usable as a comment field in .desktop
files and similar.
[originally from svn r9858]
defining it centrally per port, I think it's neater to define it for
each puzzle when adding that puzzle to the ALL list - because those
front ends which take -DCOMBINED are precisely those which use ALL.
In particular, this change opens up the possibility of compiling
both individual puzzles _and_ a combined monolith within the same
makefile.
[originally from svn r8178]
This means that puzzles.rc2 is always included in all Windows and
PocketPC builds, which in turn means that I should be able to start
filling it full of VERSIONINFO and have that reliably included as
well.
[originally from svn r7339]
infrastructure to the mkfiles.pl framework for the convenience of
the build script: it generates `wingames.lst', a list of the Windows
binaries which are ship-worthy games as opposed to nullgame or
command-line auxiliary programs.
[originally from svn r7206]
mkfiles.pl change (I don't seem to be planning ahead very well this
week), this time to provide a list of fallback options for an object
file. That way, I have a no-icon.c which quietly replaces
icons/foo-icon.c if the latter doesn't exist, and so again people
checking straight out from Subversion shouldn't have trouble.
[originally from svn r7021]
Windows puzzle binaries. This checkin involves several distinct
changes:
- mkfiles.pl now has an extra feature: if an object file is listed
in Recipe with a trailing question mark, it will be considered
optional, and silently dropped from the makefile if its primary
source file isn't present at the time mkfiles.pl runs. This means
people who check out the puzzles from Subversion and just run
mkfiles.pl shouldn't get build failures; they just won't get the
icons.
- all the .R files now use this feature to include an optional
Windows resource file.
- the .rc resource source files are built by icons/Makefile.
- windows.c finds the icon if present and uses it in place of the
standard Windows application icon.
[originally from svn r7020]
when testing a new game, so here's a new architecture for the Recipe
file. mkfiles.pl now supports several new features:
- an `!include' directive, which accepts wildcards
- += to append to an existing object group definition
- the ability to divert output to an arbitrary file.
So now each puzzle has a `.R' file containing a fragment of Recipe
code describing that puzzle, and the central Recipe does `!include
*.R' to construct the Makefiles. That way, I can keep as many
experimental half-finished puzzles lying around my working directory
as I like, and I won't have to keep reverting Recipe when I check in
any other changes.
As part of this change, list.c is no longer a version-controlled
file; it's now constructed by mkfiles.pl, so that it too can take
advantage of this mechanism.
[originally from svn r6781]
