C89 provided only double-precision mathematical functions (sin() etc),
and so despite using single-precision elsewhere, those are what Puzzles
has traditionally used. C99 introduced single-precision equivalents
(sinf() etc), and I hope it's been long enough that we can safely use
them. Maybe they'll even be faster.
Rather than directly use the single-precision functions, though, we use
the magic macros from <tgmath.h> that automatically choose the precision
of mathematical functions based on their arguments. This has the
advantage that we only need to change which header we include, and thus
that we can switch back again if some platform has trouble with the new
header.
If you define PUZZLES_INITIAL_CURSOR=y, puzzles that have a keyboard
cursor will default to making it visible rather than invisible at the
start of a new game. Behaviour is otherwise the same, so mouse actions
will cause the cursor to vanish and keyboard actions will cause it to
appear. It's just the default that has changed.
The purpose of this is for use on devices and platforms where the
primary or only means of interaction is keyboard-based. In those cases,
starting with the keyboard cursor invisible is weird and a bit
confusing.
After Ben fixed all the unwanted global functions by using gcc's
-Wmissing-declarations to spot any that were not predeclared, I
remembered that clang has -Wmissing-variable-declarations, which does
the same job for global objects. Enabled it in -DSTRICT=ON, and made
the code clean under it.
Mostly this was just a matter of sticking 'static' on the front of
things. One variable was outright removed ('verbose' in signpost.c)
because after I made it static clang was then able to spot that it was
also unused.
The more interesting cases were the ones where declarations had to be
_added_ to header files. In particular, in COMBINED builds, puzzles.h
now arranges to have predeclared each 'game' structure defined by a
puzzle backend. Also there's a new tiny header file gtk.h, containing
the declarations of xpm_icons and n_xpm_icons which are exported by
each puzzle's autogenerated icon source file and by no-icon.c. Happily
even the real XPM icon files were generated by our own Perl script
rather than being raw xpm output from ImageMagick, so there was no
difficulty adding the corresponding #include in there.
Unequal has a flags word per cell. Some of those flags are fixed,
like the locations of the ">" signs, but others indicate errors and
are used to allow the player to mark clues as "spent". Move strings
beginning with "F" allow the user to change the "spent" flags, but
they shouldn't allow the user to change any other flags, especially
those marking the constraints.
Without this fix, the following save file gives a "solver_nminmax:
Assertion `x >= 0 && y >= 0 && x < o && y < o' failed" after it adds a
clue that points off the board:
SAVEFILE:41:Simon Tatham's Portable Puzzle Collection
GAME :7:Unequal
PARAMS :3:3e0
CPARAMS :3:3e0
DESC :17:0,0,0,0,0,0,0,0,0
NSTATES :2:3
STATEPOS:1:3
MOVE :6:F2,0,4
MOVE :1:H
In commit 5030d87903191d5 I gave latin_solver_alloc a return value,
and introduced a check of that value at every call site. One of the
checks was backwards, with the effect that Unequal game generation now
more or less always fails an assertion. For example:
$ unequal --generate 1 4#12345
unequal: unequal.c:1072: gg_best_clue: Assertion `best != -1' failed.
A corrupt save file can include an "S" move that doesn't give a valid
solution. An assertion failure ("execute_move: Assertion `rc > 0'
failed.") at that point is rude, so now we just don't set the
"completed" flag in that case. We still set the "cheated" flag, to
reward (lack of) effort.
Here's a trivial test case:
SAVEFILE:41:Simon Tatham's Portable Puzzle Collection
GAME :7:Unequal
CPARAMS :1:3
PARAMS :1:3
DESC :17:0,0,0,0,0,0,0,0,0
NSTATES :1:2
STATEPOS:1:2
MOVE :10:S222222222
In the setup phase of the centralised latin.c solver, we start by
going over the input grid containing already-placed clue numbers, and
calling latin_solver_place to enter each on into the solver's data
structure. This has the side effect of ruling out each number from the
rest of the row and column, and _also_ checking by assertion that the
number being placed is not ruled out.
Those are a bad combination, because it means that if you give an
obviously inconsistent input grid to latin_solver_alloc (e.g. with two
identical numbers in a row already), it will fail an assertion. In
that situation, you want the solver run as a whole to return
diff_impossible so that the error is reported cleanly.
This assertion failure could be provoked by giving either Towers or
Group a manually-constructed game description inconsistent in that
way, and hitting Solve. Worse, it could be provoked during live play
in Unequal, by filling in a number clashing with a clue and then
pressing 'h' to get hints.
If can_configure is false, then the game's configure() and
custom_params() functions will never be called. If can_solve is false,
solve() will never be called. If can_format_as_text_ever is false,
can_format_as_text_now() and text_format() will never be called. If
can_print is false, print_size() and print() will never be called. If
is_timed is false, timing_state() will never be called.
In each case, almost all puzzles provided a function nonetheless. I
think this is because in Puzzles' early history there was no "game"
structure, so the functions had to be present for linking to work. But
now that everything indirects through the "game" structure, unused
functions can be left unimplemented and the corresponding pointers set
to NULL.
So now where the flags mentioned above are false, the corresponding
functions are omitted and the function pointers in the "game" structures
are NULL.
This applies to various square-filling games: Keen, Solo, Towers,
Undead, and Unequal. In all cases, selecting a square and pressing the
number that was already in it, or selecting an empty square and pressing
Backspace, would add a move to the undo chain that did nothing. This
also meant that the convention where Backspace from the top level of an
application in KaiOS leaves the application didn't work.
Now the various interpret_move() functions check the current state of
the grid, and return NULL or UI_UPDATE where a move wouldn't change the
board. UI_UPDATE is returned in the case where the cursor was put in
place using the mouse, because in those cases I think the cursor should
still be hidden again. NULL is returned when the cursor was put in
place by keyboard, because then there's really nothing to do.
This provides a way for the front end to ask how a particular key should
be labelled right now (specifically, for a given game_state and
game_ui). This is useful on feature phones where it's conventional to
put a small caption above each soft key indicating what it currently
does.
The function currently provides labels only for CURSOR_SELECT and
CURSOR_SELECT2. This is because these are the only keys that need
labelling on KaiOS.
The concept of labelling keys also turns up in the request_keys() call,
but there are quite a few differences. The labels returned by
current_key_label() are dynamic and likely to vary with each move, while
the labels provided by request_keys() are constant for a given
game_params. Also, the keys returned by request_keys() don't generally
include CURSOR_SELECT and CURSOR_SELECT2, because those aren't necessary
on platforms with pointing devices. It might be possible to provide a
unified API covering both of this, but I think it would be quite
difficult to work with.
Where a key is to be unlabelled, current_key_label() is expected to
return an empty string. This leaves open the possibility of NULL
indicating a fallback to button2label or the label specified by
request_keys() in the future.
It's tempting to try to implement current_key_label() by calling
interpret_move() and parsing its output. This doesn't work for two
reasons. One is that interpret_move() is entitled to modify the
game_ui, and there isn't really a practical way to back those changes
out. The other is that the information returned by interpret_move()
isn't sufficient to generate a label. For instance, in many puzzles it
generates moves that toggle the state of a square, but we want the label
to reflect which state the square will be toggled to. The result is
that I've generally ended up pulling bits of code from interpret_move()
and execute_move() together to implement current_key_label().
Alongside the back-end function, there's a midend_current_key_label()
that's a thin wrapper around the back-end function. It just adds an
assertion about which key's being requested and a default null
implementation so that back-ends can avoid defining the function if it
will do nothing useful.
The Rockbox frontend allows games to be displayed in a "zoomed-in"
state targets with small displays. Currently we use a modal interface
-- a "viewing" mode in which the cursor keys are used to pan around
the rendered bitmap; and an "interaction" mode that actually sends
keys to the game.
This commit adds a midend_get_cursor_location() function to allow the
frontend to retrieve the backend's cursor location or other "region of
interest" -- such as the player location in Cube or Inertia.
With this information, the Rockbox frontend can now intelligently
follow the cursor around in the zoomed-in state, eliminating the need
for a modal interface.
This too seems to have made no difference: each of the commands
unequal --generate 1000 6dr#12345
unequal --generate 1000 6adr#12345
delivers the same list of puzzles before and after the fix.
I've only just realised that there's a false-positive bug in the
latin.c solver framework.
It's designed to solve puzzles in which the solution is a latin square
but with some additional constraints provided by the individual
puzzle, and so during solving, it runs a mixture of its own standard
deduction functions that apply to any latin-square puzzle and extra
functions provided by the client puzzle to do deductions based on the
extra clues or constraints.
But what happens if the _last_ move in the solving process is
performed by one of the latin.c built-in methods, and it causes a
violation of the client puzzle's extra constraints? Nothing will ever
notice, and so the solver will report that the puzzle has a solution
when it actually has none.
An example is the Group game id 12i:m12b9a1zd9i6d10c3y2l11q4r . This
was reported by 'groupsolver -g' as being ambiguous. But if you look
at the two 'solutions' reported in the verbose diagnostics, one of
them is arrant nonsense: it has no identity element at all, and
therefore, it fails associativity all over the place. Actually that
puzzle _does_ have a unique solution.
This bug has been around for ages, and nobody has reported a problem.
For recursive solving, that's not much of a surprise, because it would
cause a spurious accusation of ambiguity, so that at generation time
some valid puzzles would be wrongly discarded, and you'd never see
them. But at non-recursive levels, I can't see a reason why this bug
_couldn't_ have led one of the games to present an actually impossible
puzzle believing it to be soluble.
Possibly this never came up because the other clients of latin.c are
more forgiving of this error in some way. For example, they might all
be very likely to use their extra clues early in the solving process,
so that the requirements are already baked in by the time the final
grid square is filled. I don't know!
Anyway. The fix is to introduce last-minute client-side validation:
whenever the centralised latin_solver thinks it's come up with a
filled grid, it should present it to a puzzle-specific validator
function and check that it's _really_ a legal solution.
This commit does the plumbing for all of that: it introduces the new
validator function as one of the many parameters to latin_solver, and
arranges to call it in an appropriate way during the solving process.
But all the per-puzzle validation functions are empty, for the moment.
Another thing I spotted while trawling the whole source base was that
a couple of games had omitted 'static' on a lot of their internal
functions. Checking with nm, there turned out to be quite a few more
than I'd spotted by eye, so this should fix them all.
Also added one missing 'const', on the lookup table nbits[] in Tracks.
This is the main bulk of this boolification work, but although it's
making the largest actual change, it should also be the least
disruptive to anyone interacting with this code base downstream of me,
because it doesn't modify any interface between modules: all the
inter-module APIs were updated one by one in the previous commits.
This just cleans up the code within each individual source file to use
bool in place of int where I think that makes things clearer.
This commit removes the old #defines of TRUE and FALSE from puzzles.h,
and does a mechanical search-and-replace throughout the code to
replace them with the C99 standard lowercase spellings.
encode_params, validate_params and new_desc now take a bool parameter;
fetch_preset, can_format_as_text_now and timing_state all return bool;
and the data fields is_timed, wants_statusbar and can_* are all bool.
All of those were previously typed as int, but semantically boolean.
This commit changes the API declarations in puzzles.h, updates all the
games to match (including the unfinisheds), and updates the developer
docs as well.
This function gives the front end a way to find out what keys the back
end requires; and as such it is mostly useful for ports without a
keyboard. It is based on changes originally found in Chris Boyle's
Android port, though some modifications were needed to make it more
flexible.
A user sent in the game id
7:0,0L,0,0,0L,0L,1,0U,0U,0D,0UD,0,0,7,0,0D,0,0D,0,0,0,0,0,0,0,0,0,0D,0,0,3,0,0U,0,0,0,0,2,6,0,0U,0,0,0,7,2,0,0U,5L,
starting from which, one press of 'h' will fill in a 2 in the top left
corner and possibilities 345 to its right; if you then fill in 5 there
and press 'h' again, the hint system fills in the whole of an apparent
solution which isn't the one a proper use of the Solve feature would
give you - except that it's not actually a second solution, because
one < clue on the top row is violated. Without this fix, that < failed
to light up red, making the puzzle look ambiguous if you're not paying
enough attention to spot it.
I went through all the char * parameters and return values I could see
in puzzles.h by eye and spotted ones that surely ought to have been
const all along.
This allows me to use different types for the mutable, dynamically
allocated string value in a C_STRING control and the fixed constant
list of option names in a C_CHOICES.
Now midend.c directly tests the returned pointer for equality to this
value, instead of checking whether it's the empty string.
A minor effect of this is that games may now return a dynamically
allocated empty string from interpret_move() and treat it as just
another legal move description. But I don't expect anyone to be
perverse enough to actually do that! The main purpose is that it
avoids returning a string literal from a function whose return type is
a pointer to _non-const_ char, i.e. we are now one step closer to
being able to make this code base clean under -Wwrite-strings.
To do this, I've completely replaced the API between mid-end and front
end, so any downstream front end maintainers will have to do some
rewriting of their own (sorry). I've done the necessary work in all
five of the front ends I keep in-tree here - Windows, GTK, OS X,
Javascript/Emscripten, and Java/NestedVM - and I've done it in various
different styles (as each front end found most convenient), so that
should provide a variety of sample code to show downstreams how, if
they should need it.
I've left in the old puzzle back-end API function to return a flat
list of presets, so for the moment, all the puzzle backends are
unchanged apart from an extra null pointer appearing in their
top-level game structure. In a future commit I'll actually use the new
feature in a puzzle; perhaps in the further future it might make sense
to migrate all the puzzles to the new API and stop providing back ends
with two alternative ways of doing things, but this seemed like enough
upheaval for one day.
A user points out that the error check that should have detected a
non-digit where a digit should have been was never firing, due to an
&& that should have been ||.
I don't think it was a harmful error - the subsequent check that the
number was in range, plus the skipping past only digits to find the
next part of the string, combine to arrange that not many kinds of
invalid game id could actually get through.
But it did have the small effect that a 0 could be elided without
triggering an error, e.g. the game ids
4:0,0,0,0,0,0L,0,0,0R,0U,0,0L,0,0,,3,
4:0,0,0,0,0,0L,0,0,0R,0U,0,0L,0,0,0,3,
would both be accepted, and would be decoded into the same game, even
though the former should have failed syntax validation. Now it does.
puzzle backend function which ought to have it, and propagate those
consts through to per-puzzle subroutines as needed.
I've recently had to do that to a few specific parameters which were
being misused by particular puzzles (r9657, r9830), which suggests
that it's probably a good idea to do the whole lot pre-emptively
before the next such problem shows up.
[originally from svn r9832]
[r9657 == 3b250baa02a7332510685948bf17576c397b8ceb]
[r9830 == 0b93de904a98f119b1a95d3a53029f1ed4bfb9b3]
new_desc. Oddities in the 'make test' output brought to my attention
that a few puzzles have been modifying their input game_params for
various reasons; they shouldn't do that, because that's the
game_params held permanently by the midend and it will affect
subsequent game generations if they modify it. So now those arguments
are const, and all the games which previously modified their
game_params now take a copy and modify that instead.
[originally from svn r9830]
basically just so that it can divide mouse coordinates by the tile
size, but is definitely not expected to _write_ to it, and it hadn't
previously occurred to me that anyone might try. Therefore,
interpret_move() now gets a pointer to a _const_ game_drawstate
instead of a writable one.
All existing puzzles cope fine with this API change (as long as the
new const qualifier is also added to a couple of subfunctions to which
interpret_move delegates work), except for the just-committed Undead,
which somehow had ds->ascii and ui->ascii the wrong way round but is
otherwise unproblematic.
[originally from svn r9657]
midend_status(), and given it three return codes for win, (permanent)
loss and game-still-in-play. Depending on what the front end wants to
use it for, it may find any or all of these three states worth
distinguishing from each other.
(I suppose a further enhancement might be to add _non_-permanent loss
as a fourth distinct status, to describe situations in which you can't
play further without pressing Undo but doing so is not completely
pointless. That might reasonably include dead-end situations in Same
Game and Pegs, and blown-self-up situations in Mines and Inertia.
However, I haven't done this at present.)
[originally from svn r9179]
that we can pass -1 in calls from game_print(). Fixes a printing bug
in which all the adjs and gts were overlaid with giant black
rectangles! (Because COL_BACKGROUND doesn't mean the same thing in
that context.)
[originally from svn r9175]
thereafter read. Most of these changes are just removal of pointless
stuff or trivial reorganisations; one change is actually substantive,
and fixes a bug in Keen's clue selection (the variable 'bad' was
unreferenced not because I shouldn't have set it, but because I
_should_ have referenced it!).
[originally from svn r9164]
state is in a solved position, and a midend function wrapping it.
(Or, at least, a situation in which further play is pointless. The
point is, given that game state, would it be a good idea for a front
end that does that sort of thing to proactively provide the option to
start a fresh game?)
[originally from svn r9140]
their coordinate from 1 rather than 0, for consistency with Solo.
(My geek instincts would rather work from 0, but I've generally
found that puzzle users sending me email tend to prefer 1.)
[originally from svn r8795]
programs having to clone the latin_solver() function and insert
their own extra deduction routines, they can now just _call_
latin_solver with enough parameters to let it fit its own deductions
into their difficulty framework and call a set of provided function
pointers to do user deductions. Modified Unequal to work in the new
world, of course.
[originally from svn r8791]
the < and > clues are replaced by bars separating every pair of
squares whose contents differ by exactly 1. Unlike standard Unequal,
which presents only a subset of the available clues, in Adjacent the
clues are _all_ present, so you can deduce from the absence of a bar
that the two numbers it would separate are _not_ consecutive.
[originally from svn r8790]
Guess, because Guess expected ^H whereas GTK generated ^?. Other
puzzles that use Backspace do it by being prepared to see either,
which seems wasteful. Now the midend normalises both into ^H, so
front ends can generate whichever they like while puzzles can
safely just look for ^H.
[originally from svn r8786]
of 'h' and 'm' are treated as digits if a square is selected, and
only treated as special commands otherwise. This renders very large
games (just about) playable.
Idea from Ben Hutchings's collection of Debian patches, although I
had to redo his (trivial) patch myself since the code has changed
recently.
(Addendum after committing: hmm, I see Jacob already applied the
original version of the patch a while back. Looks as if the recent
keyboard control change reintroduced the problem. Still, re-fixed
now.)
[originally from svn r8433]
and also updates the docs for both that and the Mines cursor support
in r8402.
[originally from svn r8408]
[r8402 == f20847354cb6335fd349204f16021a72e2956cce]
Unequal 18x18 or above was unplayable due to a clash with the undocumented
"H" (hint) key. Resolve the clash by making the hint function only fire
when no square is selected.
[originally from svn r8200]