56 Commits

Author SHA1 Message Date
5de69c22b0 Refactor button & ~MOD_MASK' as STRIP_BUTTON_MODIFIERS(button)'.
This refactors all instances of bitwise-ANDs with `~MOD_MASK'. There is
a handful of more complex instances I left unchanged (in cube.c, midend.c,
and twiddle.c), since those AND with `~MOD_MASK | MOD_NUM_KEYPAD' or
similar. I don't think it's worth writing a macro for those cases.

Also document this new macro's usage in devel.but.
2024-07-31 23:29:00 +01:00
3243a1fd77 Wrap a few long lines in Keen 2023-12-06 22:39:14 +00:00
df2d6d347e Keen: use new move_cursor() features 2023-08-13 16:44:24 +01:00
a11ee53ef8 Keen, Solo, Towers, Undead, Unequal, Group: new UI preference.
If you're using the mouse to change pencil marks, you have to
right-click to pencil-highlight a square, then press a number or
letter key to add or remove a highlight. That causes the highlight to
vanish again. So adding or removing multiple pencil marks requires a
right-click + keypress per mark.

Chris's Android port reversed that decision, making the pencil
highlight persist so that you could 'click' just once and then press
multiple pencil keys. That makes it easier to add lots of highlights,
but harder to just remove a single one (click + press + click to
remove the highlight), unless you don't mind keeping the highlight
around afterwards cluttering up your view.

In other words, this is just the sort of thing users might reasonably
disagree on. So now we have an organised preferences system, we can
let them disagree, and each configure it whichever way they like!

This only affects mouse-based play. The keyboard cursor has _always_
worked this way, because it doesn't disappear at all; its behaviour is
unchanged, and independent of the new preference.
2023-08-13 14:35:50 +01:00
5ec86c03a8 move_cursor(): handle visible flag; return useful value
This adds an extra parameter to move_cursor() that's an optional pointer
to a bool indicating whether the cursor is visible.  This allows for
centralising the common idiom of having the keyboard cursor become
visible when a cursor key is pressed.  Consistently with the vast
majority of existing puzzles, the cursor moves even if it was invisible
before, and becomes visible even if it can't move.

The function now also returns one of the special constants that can be
returned by interpret_move(), so that the caller can correctly return
MOVE_UI_UPDATE or MOVE_NO_EFFECT without needing to carefully check for
changes itself.

Callers are updated only to the extent that they all pass NULL as the
new argument.  Most of them could now be substantially simplified.
2023-08-09 11:44:25 +01:00
c5076be383 Keen: fix another misuse of dsf_canonify.
Chris Boyle points out that outline_block_structure has a comment
saying that we're supposed to have picked a square with a boundary to
its left. dsf_canonify no longer guarantees that, but dsf_minimal
does. Switch to using that throughout the function.

'keen --generate 10#12345 --print 5x2' failed an assertion before this
fix, and now doesn't.
2023-06-25 15:40:58 +01:00
a9af3fda1d Rename UI_UPDATE as MOVE_UI_UPDATE
All the other constants named UI_* are special key names that can be
passed to midend_process_key(), but UI_UPDATE is a special return value
from the back-end interpret_move() function instead.  This renaming
makes the distinction clear and provides a naming convention for future
special return values from interpret_move().
2023-06-11 00:33:27 +01:00
0058331aeb New backend functions: get_prefs and set_prefs.
These are similar to the existing pair configure() and custom_params()
in that get_prefs() returns an array of config_item describing a set
of dialog-box controls to present to the user, and set_prefs()
receives the same array with answers filled in and implements the
answers. But where configure() and custom_params() operate on a
game_params structure, the new pair operate on a game_ui, and are
intended to permit GUI configuration of all the settings I just moved
into that structure.

However, nothing actually _calls_ these routines yet. All I've done in
this commit is to add them to 'struct game' and implement them for the
functions that need them.

Also, config_item has new fields, permitting each config option to
define a machine-readable identifying keyword as well as the
user-facing description. For options of type C_CHOICES, each choice
also has a keyword. These keyword fields are only defined at all by
the new get_prefs() function - they're left uninitialised in existing
uses of the dialog system. The idea is to use them when writing out
the user's preferences into a configuration file on disk, although I
haven't actually done any of that work in this commit.
2023-04-23 13:25:06 +01:00
a4fca3286f Pass a game_ui to compute_size, print_size and print.
I'm about to move some of the bodgy getenv-based options so that they
become fields in game_ui. So these functions, which could previously
access those options directly via getenv, will now need to be given a
game_ui where they can look them up.
2023-04-21 16:18:04 +01:00
c5e253a9f9 Reorganise the dsf API into three kinds of dsf.
This is preparing to separate out the auxiliary functionality, and
perhaps leave space for making more of it in future.

The previous name 'edsf' was too vague: the 'e' stood for 'extended',
and didn't say anything about _how_ it was extended. It's now called a
'flip dsf', since it tracks whether elements in the same class are
flipped relative to each other. More importantly, clients that are
going to use the flip tracking must say so when they allocate the dsf.

And Keen's need to track the minimal element of an equivalence class
is going to become a non-default feature, so there needs to be a new
kind of dsf that specially tracks those, and Keen will have to call it.

While I'm here, I've renamed the three dsf creation functions so that
they start with 'dsf_' like all the rest of the dsf API.
2023-04-20 18:39:41 +01:00
14e1e05510 Introduce a new dsf_equivalent() function.
Not very interesting, but the idiom for checking equivalence via two
calls to dsf_canonify is cumbersome enough to be worth abbreviating.
2023-04-20 18:39:35 +01:00
348aac4c85 Remove size parameter from dsf init and copy functions.
Now that the dsf knows its own size internally, there's no need to
tell it again when one is copied or reinitialised.

This makes dsf_init much more about *re*initialising a dsf, since now
dsfs are always allocated using a function that will initialise them
anyway. So I think it deserves a rename.
2023-04-20 17:30:03 +01:00
89c438e149 Declare all dsfs as a dedicated type name 'DSF'.
In this commit, 'DSF' is simply a typedef for 'int', so that the new
declaration form 'DSF *' translates to the same type 'int *' that dsfs
have always had. So all we're doing here is mechanically changing type
declarations throughout the code.
2023-04-20 17:23:21 +01:00
bb561ee3b1 Use a dedicated free function to free dsfs.
No functional change: currently, this just wraps the previous sfree
call.
2023-04-20 17:21:12 +01:00
418cb3a567 Make encode_ui() and decode_ui() optional in back-ends
The majority of back-ends define encode_ui() to return NULL and
decode_ui() to do nothing.  This commit allows them to instead specify
the relevant function pointers as NULL, in which case the mid-end won't
try to call them.

I'm planning to add a parameter to decode_ui(), and if I'm going to have
to touch every back-end's version of decode_ui(), I may as well ensure
that most of them never need to be touched again.  And obviously
encode_ui() should go the same way for symmetry.
2023-04-08 20:08:16 +01:00
3b9cafa09f Fall back to <math.h> if <tgmath.h> doesn't work.
This fixes a build failure introduced by commit 2e48ce132e011e8
yesterday.

When I saw that commit I expected the most likely problem would be in
the NestedVM build, which is currently the thing with the most most
out-of-date C implementation. And indeed the NestedVM toolchain
doesn't have <tgmath.h> - but much more surprisingly, our _Windows_
builds failed too, with a compile error inside <tgmath.h> itself!

I haven't looked closely into the problem yet. Our Windows builds are
done with clang, which comes with its own <tgmath.h> superseding the
standard Windows one. So you'd _hope_ that clang could make sense of
its own header! But perhaps the problem is that this is an unusual
compile mode and hasn't been tested.

My fix is to simply add a cmake check for <tgmath.h> - which doesn't
just check the file's existence, it actually tries compiling a file
that #includes it, so it will detect 'file exists but is mysteriously
broken' just as easily as 'not there at all'. So this makes the builds
start working again, precisely on Ben's theory of opportunistically
using <tgmath.h> where possible and falling back to <math.h>
otherwise.

It looks ugly, though! I'm half tempted to make a new header file
whose job is to include a standard set of system headers, just so that
that nasty #ifdef doesn't have to sit at the top of almost all the
source files. But for the moment this at least gets the build working
again.
2023-04-06 07:08:04 +01:00
2e48ce132e Replace <math.h> with <tgmath.h> throughout
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.
2023-04-04 21:43:25 +01:00
6dac51795e Add an environment variable to control initial cursor visibility
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.
2023-03-22 16:58:22 +00:00
bb31efdbc9 Fix memory leaks in Keen's validate_desc()
Keen uses a DSF to validate its game descriptions and almost always
failed to free it, even when the validation succeeded.
2023-02-13 09:39:04 +00:00
789e11f8f8 Remove various unused game functions
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.
2023-01-31 23:25:05 +00:00
4ec2c58045 When filling in or blanking a square, don't generate null moves
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.
2022-12-27 15:18:42 +00:00
a3310ab857 New backend function: current_key_label()
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.
2022-12-09 20:48:30 +00:00
c0da615a93 Centralise initial clearing of the puzzle window.
I don't know how I've never thought of this before! Pretty much every
game in this collection has to have a mechanism for noticing when
game_redraw is called for the first time on a new drawstate, and if
so, start by covering the whole window with a filled rectangle of the
background colour. This is a pain for implementers, and also awkward
because the drawstate often has to _work out_ its own pixel size (or
else remember it from when its size method was called).

The backends all do that so that the frontends don't have to guarantee
anything about the initial window contents. But that's a silly
tradeoff to begin with (there are way more backends than frontends, so
this _adds_ work rather than saving it), and also, in this code base
there's a standard way to handle things you don't want to have to do
in every backend _or_ every frontend: do them just once in the midend!

So now that rectangle-drawing operation happens in midend_redraw, and
I've been able to remove it from almost every puzzle. (A couple of
puzzles have other approaches: Slant didn't have a rectangle-draw
because it handles even the game borders using its per-tile redraw
function, and Untangle clears the whole window on every redraw
_anyway_ because it would just be too confusing not to.)

In some cases I've also been able to remove the 'started' flag from
the drawstate. But in many cases that has to stay because it also
triggers drawing of static display furniture other than the
background.
2021-04-25 13:07:59 +01:00
78bc9ea7f7 Add method for frontends to query the backend's cursor location.
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.
2020-12-07 19:40:06 +00:00
8110518c33 Keen: fill in the latin.c validator function.
This seems to make no difference that I can detect: a test generation
run of the form 'keen --generate 1000 6du#12345' outputs an identical
list of 1000 puzzle ids before and after. So the missing validation in
this puzzle seems to have been benign.
2020-05-23 09:48:07 +01:00
f21d3e4c74 latin.c: call a user-provided validator function. [NFC]
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.
2020-05-23 09:08:08 +01:00
5f5b284c0b Use C99 bool within source modules.
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.
2018-11-13 21:48:24 +00:00
a550ea0a47 Replace TRUE/FALSE with C99 true/false throughout.
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.
2018-11-13 21:48:24 +00:00
a76d269cf2 Adopt C99 bool in the game backend API.
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.
2018-11-13 21:34:42 +00:00
32f96080ad Enable 64-bit osx build and fix a warning.
OS X is beginning to show a warning when a 32-bit application is
opened, so it's high time that this gets enabled. Fix a clang warning
exposed by this build.
2018-06-01 06:50:15 +01:00
b3da23806e Move `static' keyword to beginning of declaration.
Rockbox's GCC warns about this with -Wextra.
2018-04-24 21:32:56 +01:00
60a929a250 Add a request_keys() function with a midend wrapper.
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.
2018-04-22 17:04:50 +01:00
a58c1b216b Make the code base clean under -Wwrite-strings.
I've also added that warning option and -Werror to the build script,
so that I'll find out if I break this property in future.
2017-10-01 16:35:40 +01:00
b3243d7504 Return error messages as 'const char *', not 'char *'.
They're never dynamically allocated, and are almost always string
literals, so const is more appropriate.
2017-10-01 16:34:41 +01:00
de67801b0f Use a proper union in struct config_item.
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.
2017-10-01 16:34:41 +01:00
eeb2db283d New name UI_UPDATE for interpret_move's return "".
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.
2017-10-01 15:18:14 +01:00
a7dc17c425 Rework the preset menu system to permit submenus.
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.
2017-04-26 21:51:23 +01:00
55683abd97 Fix a valgrind warning in the Keen DIFF_HARD solver code.
The solver's array ctx->iscratch[] is used for a completely different
purpose in the DIFF_HARD code, compared to what it's used for in
DIFF_EASY and DIFF_NORMAL. In particular, a different number of
elements of the array are used - but the code which sets up the array
was not correctly initialising all of them.

I was also unable to find any clear comment that even explained _that_
the purpose of the array was entirely different between the two cases,
let alone explaining _what_ the two purposes were. So I've written
some comments as part of this commit, which should make things a bit
less confusing next time. (Though not much, I admit.)
2016-01-03 09:51:15 +00:00
47bc27b0c2 Add 'Inshi No Heya' (multiplication only) variant to Keen. 2015-10-03 17:12:20 +01:00
6482ed0e3c Fix a display glitch in Keen's pencil-mode cursor.
Draw pencil-mode cursor before corners of thick lines in order to make
the thick lines appear on top of the north-west corner of the pencil
cursor, just like they do with the non-pencil cursor.
2015-10-03 17:12:20 +01:00
251b21c418 Giant const patch of doom: add a 'const' to every parameter in every
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]
2013-04-13 10:37:32 +00:00
0b93de904a Add 'const' to the game_params arguments in validate_desc and
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]
2013-04-12 17:11:49 +00:00
c94afe9cd6 Adjust Keen's grid generation to constrain the maximum size of clue
blocks, because 'make test' showed up very large blocks as an
occasional slowdown factor in game generation (takes too long to
iterate over all possibilities). This is a good idea in any case,
because really big multiplicative clue numbers have trouble fitting in
the square.

[originally from svn r9827]
2013-04-12 16:28:53 +00:00
3b250baa02 New rule: interpret_move() is passed a pointer to the game_drawstate
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]
2012-09-09 18:40:12 +00:00
73daff3937 Changed my mind about midend_is_solved: I've now reprototyped it as
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]
2011-06-19 13:43:35 +00:00
bd539ae870 Having played Keen a bit following the clue-generation fix in r9165,
I've decided that the extremely low density of one-option
multiplication clues is not a universally good idea after all: it
seems to me to make puzzles _quantitatively_ harder, even if Keen's
difficulty-level system can't see any difference in the set of modes
of reasoning required at least once to solve the grid.

So I've readjusted the clue selection, so that multiplicative clues
with only one workable pair of factors are restored to 'good' status
at Normal difficulty level and below, and only considered less-than-
fully-desirable at Hard and above. I think that's a reasonable
compromise.

[originally from svn r9170]
[r9165 == e7b2a9dd8d8915802fb69ce2242b1f913b7f3172]
2011-05-07 13:22:17 +00:00
e7b2a9dd8d Having looked at Keen's clue selection code, I also notice that the
intended behaviour of classifying multiplication clues as low-quality
if they only left one possible pair of multiplicands has never
actually worked, because I should have compared the possible clue
count against 2 rather than 1 since the multiplicands can occur either
way round.

[originally from svn r9165]
2011-05-04 18:22:15 +00:00
2efc77d2fd Fix warnings generated by gcc 4.6.0 about variables set but not
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]
2011-05-04 18:22:14 +00:00
980880be1f Add a function to every game backend which indicates whether a game
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]
2011-04-02 16:19:12 +00:00
19fa275b6a Patch from Ben Hutchings to fix an error-checking goof: Keen
division clues were failing to light up as erroneous if the quotient
of the numbers in them came out right under rounded-down C integer
division (e.g. 2 and 5 would be accepted for a 2/ clue). Apparently
I copied the code that invents clues in the generator straight into
the solution checker, without remembering that the generator was
allowed to do it that way because exact divisibility had been
checked elsewhere.

[originally from svn r8951]
2010-05-16 06:58:09 +00:00