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.
For reasons now lost to history, Puzzles generally uses single-precision
floating point. However, C floating-point constants are by default
double-precision, and if they're then operated on along with a
single-precision variable the value of the variable gets promoted to
double precision, then the operation gets done, and then often the
result gets converted back to single precision again.
This is obviously silly, so I've used Clang's "-Wdouble-promotion" to
find instances of this and mark the constants as single-precision as
well. This is a bit awkward for PI, which ends up with a cast. Maybe
there should be a PIF, or maybe PI should just be single-precision.
This doesn't eliminate all warnings from -Wdouble-promotion. Some of
the others might merit fixing but adding explicit casts to double just
to shut the compiler up would be going too far, I feel.
sscanf() assigns its output in order, so if a conversion specifier fails
to match, a later "%n" specifier will also not get its result assigned.
In Undead's execute_move(), this led to the result of "%n" being used
without being initialised. That could cause it to try to parse
arbitrary memory as part of the move string, which shouldn't be a
security problem (since execute_move() handles untrusted input anyway),
but could lead to a crash and certainly wasn't helpful.
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.
Normal moves shouldn't be allowed to write outside the board. This
buffer overrun can be demonstrated by building Undead with
AddressSanitizer and loading this save file:
SAVEFILE:41:Simon Tatham's Portable Puzzle Collection
VERSION :1:1
GAME :6:Undead
PARAMS :5:4x4dn
CPARAMS :5:4x4dn
DESC :48:5,0,5,cRRaLRcLRc,0,2,1,3,1,0,0,3,4,3,2,3,4,2,1,1
NSTATES :1:2
STATEPOS:1:2
MOVE :3:Z10
The guessable squares are numbered up to num_total, not "wh". The
latter includes mirror squares that aren't included in the various
arrays describing the game state.
To reproduce the problem, build Undead with AddressSanitizer and press
"M".
Previously, Undead's execute_move would go into a spin when it
encountered an unexpected command character in a move string. Now it
rejects the move instead.
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.
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.
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.
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.
I noticed that state->common, which is shared between all the game
states in an undo chain, has a 'solved' flag in it. That's not right -
solvedness as a property of a particular state on the chain belongs in
the game_state itself, and having-at-one-point-been-solved-ness as a
persistent property of the whole chain belongs in the game_ui.
Fortunately, the game isn't actually doing it wrong:
state->common->solved is set once and then never read, so it must have
been left in from early abandoned code. Now removed.
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.
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.
- Mark a clue as an error if too many monsters are seen, even if
some squares are empty.
- Mark a clue as an error if too few monsters are seen, taking into
account how many more sightings are possible given the number of
empty squares and how many times each of them are visited.
Keen, Towers and Unequal (and Group) already have this feature in
common: pressing m while no square is selected, causes a full set of
pencil marks to be filled in for every square without a real number/
letter/whatever in it. Solo and Undead share the basic UI principles
(left-click to select a square then type a thing to go in it, vs
right-click to select a square then type things to pencil-mark in it),
but did not have that same feature. Now they do.
The is_hint_stale() function has the side effect of copying a path
hint's new colour-relevant information into the game_drawstate, where
draw_path_hint will then use it. But it returns TRUE early in some
situations, notably !ds->started, which can happen after the actual
game start if the window is resized and a fresh drawstate is created.
This patch, thanks to Chris Boyle, fixes it by eliminating the early
returns from is_hint_stale - the return value is unchanged, but now
the side effects happen reliably.
Now they're centred within the spare grid cell at the top of the
playing area, rather than being too far down so that the bottoms of
the monster drawings collide with the background of the path clues at
large magnification. Also, while I'm here, I've simplified the code
that draws the monster counts, by moving duplicated parts out of the
branches of the 'if'.
(In fact, almost all of this patch is cleanup; the only substantive
change is the one that changes dy from TILESIZE/2 to TILESIZE/4.)
[originally from svn r10108]
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]
not only enumerating all possible arrangements of monsters along a
sight-line in O(3^n) time, but also allocated memory for them all and
then does a quadratic-time loop over that list to find arrangements
with a unique visibility count from both ends. Spotted by the new
'make test', which observed that 7x7dn#517035041807425 took 45 seconds
to generate.
This revised version still does the initial O(3^n) enumeration, which
can probably be got rid of as well with a bit more thought, but it now
doesn't allocate nearly so much memory and it spots uniques
efficiently. The above random seed now generates the same game ID in
less than a second, which drops this puzzle off the 'make test' hit
list of things most obviously needing speedup.
[originally from svn r9826]
rectangle, which showed up on the Javascript front end since the JS
canvas doesn't start out defaulting to COL_BACKGROUND. Fixed it to
draw_update to the edge of its area, and while I'm at it, narrowed the
border (since this proves we didn't really need that much space
anyway).
[originally from svn r9795]
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]
'Haunted Mirror Maze', a game involving placing ghosts, zombies and
vampires in a grid so that the right numbers of them are visible along
sight-lines reflected through multiple mirrors.
[originally from svn r9652]
