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.
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.
This fixes an amusing UI bug that I think can currently only come up
in the unpublished puzzle 'Group', but there's no reason why other
puzzles _couldn't_ do the thing that triggers the bug, if they wanted
to.
Group has unusual keyboard handling, in that sometimes (when a cell is
selected for input and the key in question is valid for the current
puzzle size) the game's interpret_move function will eat keystrokes
like 'n' and 'u' that would otherwise trigger special UI events like
New Game or Undo.
The bug is that fake keypress events generated from the GUI menus
looked enough like those keystrokes that interpret_move would eat
those too. So if you start, say, a 16x16 Group puzzle, select an empty
cell, and then choose 'new game' from the menu, Group will enter 'n'
into the cell instead of starting a new game!
I've fixed this by inventing a new set of special keystroke values
called things like UI_NEWGAME and UI_UNDO, and having the GUI menus in
all my front ends generate those in place of 'n' and 'u'. So now the
midend can tell the difference between 'n' on the keyboard and New
Game from the menu, and so Group can treat them differently too. In
fact, out of sheer overcaution, midend.c will spot keystrokes in this
range and not even _pass_ them to the game back end, so Group
shouldn't be able to override these special events even by mistake.
One fiddly consequence is that in gtk.c I've had to rethink the menu
accelerator system. I was adding visible menu accelerators to a few
menu items, so that (for example) 'U' and 'R' showed up to the right
of Undo and Redo in the menu. Of course this had the side effect of
making them real functioning accelerators from GTK's point of view,
which activate the menu item in the same way as usual, causing it to
send whatever keystroke the menu item generates. In other words,
whenever I entered 'n' into a cell in a large Group game, this was the
route followed by even a normal 'n' originated from a real keystroke -
it activated the New Game menu item by mistake, which would then send
'n' by mistake instead of starting a new game!
Those mistakes cancelled each other out, but now I've fixed the
latter, I've had to fix the former too or else the GTK front end would
now undo all of this good work, by _always_ translating 'n' on the
keyboard to UI_NEWGAME, even if the puzzle would have wanted to treat
a real press of 'n' differently. So I've fixed _that_ in turn by
putting those menu accelerators in a GtkAccelGroup that is never
actually enabled on the main window, so the accelerator keys will be
displayed in the menu but not processed by GTK's keyboard handling.
(Also, while I was redoing this code, I've removed the logic in
add_menu_item_with_key that reverse-engineered an ASCII value into
Control and Shift modifiers plus a base key, because the only
arguments to that function were fixed at compile time anyway so it's
easier to just write the results of that conversion directly into the
call sites; and I've added the GTK_ACCEL_LOCKED flag, in recognition
of the fact that _because_ these accelerators are processed by a weird
mechanism, they cannot be dynamically reconfigured by users and
actually work afterwards.)
Rockbox's sprintf() lacks the ability to left-justify a string. Fixed
by adding a copy_left_justfied() function to misc.c.
This is a new version of this commit, as the previous version broke
saving!
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.
In the course of another recent project I had occasion to read up on
Tarjan's bridge-finding algorithm. This analyses an arbitrary graph
and finds 'bridges', i.e. edges whose removal would increase the
number of connected components. This is precisely the dual problem to
error-highlighting loops in games like Slant that don't permit them,
because an edge is part of some loop if and only if it is not a
bridge.
Having understood Tarjan's algorithm, it seemed like a good idea to
actually implement it for use in these puzzles, because we've got a
long and dishonourable history of messing up the loop detection in
assorted ways and I thought it would be nice to have an actually
reliable approach without any lurking time bombs. (That history is
chronicled in a long comment at the bottom of the new source file, if
anyone is interested.)
So, findloop.c is a new piece of reusable library code. You run it
over a graph, which you provide in the form of a vertex count and a
callback function to iterate over the neighbours of each vertex, and
it fills in a data structure which you can then query to find out
whether any given edge is part of a loop in the graph or not.
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]
when the user pressed 'n' for a new game, because all the front end
knows is that it passed a keystroke to the puzzle, and it has no way
of hearing back that a particular keypress resulted in a game id
change.
To fix this, I've renamed midend_request_desc_changes to
midend_request_id_changes and expanded its remit to cover _any_ change
to the game ids. So now that callback in the Emscripten front end is
the only place from which update_permalinks is called (apart from
initialising them at setup time), and that should handle everything.
[originally from svn r9805]
can trigger a call to a front end notification function. Use this to
update the game ID permalink when Mines supersedes its game ID.
[originally from svn r9793]
The Windows puzzles now accept similar command-line syntax to the GTK
ones, in that you can give them either a game ID (descriptive, random
or just plain params) or the name of a save file. Unlike the GTK ones,
however, the save file interpretation is tried first; this is because
some puzzles (e.g. Black Box) will interpret any old string as a valid
(if boring) game ID, and unlike the GTK puzzles it's not feasible to
require users to disambiguate via a command-line option, because on
Windows a thing that might easily happen is that a user passes a save
file to a puzzle binary via 'Open With' in the GUI shell, where they
don't get the chance to add extra options.
In order to make this work sensibly in the all-in-one Windows app, I
had to get round to another thing I've been planning to do for a
while, which is to write a function to examine a saved game file and
find out which puzzle it's for. So the combined Windows binary will
auto-switch to the right game if you pass a save file on its command
line, and also if you use Load while the program is running.
Another utility function I needed is one to split the WinMain single
command line string into argv. For this I've imported a copy of
split_into_argv() from Windows PuTTY (which doesn't affect this
package's list of copyright holders, since that function was all my
own code anyway).
[originally from svn r9749]
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]
in the 'unfinished' directory for a while, and has now been finished
up thanks to James Harvey putting in some effort and galvanising me to
put in the rest. This is 'Pearl', an implementation of Nikoli's 'Masyu'.
The code in Loopy that generates a random loop along grid edges to use
as the puzzle solution has been abstracted out into loopgen.[ch] so
that Pearl can use it for its puzzle solutions too. I've also
introduced a new utility module called 'tdq' (for 'to-do queue').
[originally from svn r9379]
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]
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]
the drawing API, for use by Loopy. It's optional: drawing.c will
construct an acceptable alternative using a filled polygon if the
front end doesn't provide it.
Net and Netslide previously had static functions called
draw_thick_line(), whose claim to the name is less justified and so
they've been renamed.
[originally from svn r8962]
new function in the drawing API which permits the display of text
from outside basic ASCII. A fallback mechanism is provided so that
puzzles can give a list of strings they'd like to display in order
of preference and the system will return the best one it can manage;
puzzles are required to cope with ASCII-only front ends.
[originally from svn r8793]
alongside the individual puzzle binaries, on Windows only. (MacOS
already has it, of course; Unix would require about as much work
again.)
[originally from svn r8396]
_conditionally_ able to format the current puzzle as text to be sent
to the clipboard. For instance, if a game were to support playing on
a square grid and on other kinds of grid such as hexagonal, then it
might reasonably feel that only the former could be sensibly
rendered in ASCII art; so it can now arrange for the "Copy" menu
item to be greyed out depending on the game_params.
To do this I've introduced a new backend function
(can_format_as_text_now()), and renamed the existing static backend
field "can_format_as_text" to "can_format_as_text_ever". The latter
will cause compile errors for anyone maintaining a third-party front
end; if any such person is reading this, I apologise to them for the
inconvenience, but I did do it deliberately so that they'd know to
update their front end.
As yet, no checked-in game actually uses this feature; all current
games can still either copy always or copy never.
[originally from svn r8161]
currently selected preset, if any. I've used this in the GTK front
end to have the Type menu mark the currently selected menu item.
(After considerable beating of GTK with sticks, I might add. Grr.)
Currently the same UI feature is not yet supported on Windows or
MacOS, but I hope to do those too at some point if it's feasible.
[originally from svn r7980]
(require both main diagonals to have one of every digit in addition
to all the usual constraints) and Jigsaw Sudoku (replace the array
of rectangular sub-blocks with the sub-blocks being random
polyominoes). To implement the latter, I've moved my `divvy.c'
library routine out of the `unfinished' subdirectory.
Jigsaw mode is currently an undocumented feature: you enable it by
setting the rows parameter to 1 (and the columns parameter to your
desired grid size, which unlike normal Sudoku can be anything you
like including a prime number). The reason it's undocumented is
because generation times are not yet reliably short: sometimes
generating a jigsaw-type puzzle can hang for hours and still get
nowhere. (The algorithm should terminate in principle, but not in
any time you're prepared to wait.) I _think_ I know how to solve
this, but have yet to try it. Until then, jigsaw mode will remain a
hidden feature.
Printing of X-type puzzles is also substandard at present, because
the current print-colour API replaces the desired light shading of
the X-cells with heavy diagonal hatching. I plan to adjust the API
imminently to address this.
[originally from svn r7974]
is mostly done with ifdefs in windows.c; so mkfiles.pl generates a
new makefile (Makefile.wce) and Recipe enables it, but it's hardly
any different from Makefile.vc apart from a few definitions at the
top of the files.
Currently the PocketPC build is not enabled in the build script, but
with any luck I'll be able to do so reasonably soon.
[originally from svn r7337]
the web, which I hope will also end up being extended to generate
both Windows and X icons for each individual puzzle. The mechanism
is: for each puzzle there's a save file in the `icons' subdirectory
showing a game state which I think is a decent illustration of the
puzzle, and then there's a nasty set of scripts which runs each
puzzle binary, loads that save file, grabs a screenshot using xwd,
and munges it into shape.
In order to support this I've added two new options (--redo and
--windowid) to all the GTK puzzles, which I don't expect ever to be
used outside the icons makefile. I've also added two more options
(--load and --id) which force a GTK puzzle to treat its command-line
option as a save file or as a game ID respectively (the previous
behaviour was always to guess, and sometimes it guessed wrong).
[originally from svn r7014]
midend_rewrite_statusbar() and check the result against the last
string returned. This is now done centrally in drawing.c, and the
front end status bar function need only do what it says on the tin.
While I'm modifying the prototype of drawing_init(), I've also
renamed it drawing_new() for the same reason as random_new() (it
_allocates_ a drawing object, rather than just initialising one
passed in).
[originally from svn r6420]
function, since it took no parameters by which to vary its decision,
and in any case it's hard to imagine a game which only
_conditionally_ wants a status bar. Changed it into a boolean data
field in the backend structure.
[originally from svn r6417]
