The capability to navigate ships spread over several sectors is
obscure and rarely useful. Accidental use is probably more frequent
than intentional use. Issues:
* Interactive prompts show only the flagship's position, and give no
clue that some ships are actually elsewhere.
* Path finding is supported only when all navigating ships are in
the same sector.
* Interdiction becomes rather complex. For each movement, every
sector entered is interdicted independently. This means the same
fort, ship, land unit or plane can interdict multiple times.
Interdiction order depends on the order the code examines
ships. which the player can control. This is all pretty much
undocumented.
* Complicates the code and its maintenance. Multiplies the number of
test cases needed to cover navigate.
I feel we're better off without this feature.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
With autonav and SAIL gone, shp_nav_put() isn't used externally
anymore. lnd_mar_put() never was; it got external linkage just for
symmetry.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
SAIL has issues:
* Sail orders are executed at the update. Crafty players can use them
to get around the update window.
* The route is fixed at command time. You can't let the update find
the best route, like it does for distribution.
* The info pages documenting it amount to almost 100 non-blank lines
formatted. They claim you can follow friendly ships. This is
wrong. They also show incorrect follow syntax. Unlikely to be the
only errors.
* Few players use it. Makes it a nice hidey-hole for bugs. Here are
two nice ones:
- If follow's second argument is negative, the code attempts to
follow an uninitialized ship. Could well be a remote hole.
- If ship #1 follows #2 follows #3 follows #2, the update goes into
an infinite loop.
* It's more than 500 lines of rather crufty code nobody wants to
touch. Thanks to a big effort in Empire 2, it shares some code with
the navigation command. It still duplicates other navigation code.
The sharing complicates fixing the bugs demonstrated by
navi-march-test.
Reviewing, fixing and testing this mess isn't worth the opportunity
cost. Remove it instead. Drop commands follow, mquota, sail and
unsail. Drop ship selectors mquota, path, follow.
struct shpstr shrinks some more, on my system from 160 to 120 bytes.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
The autonavigation feature has issues:
* Autonavigation orders are executed at the update. Crafty players
can use them to get around the update window.
* Usability is poor:
- The order command is overly complex, not least because it can do
five different things: clear, suspend, resume, declare route, set
cargo levels.
- Unlike every other command involving movement, order does not let
you specify routes, only destination sectors.
- Setting cargo levels can silently swap start and end point of a
circular route, because "this keeps the load_it() procedure
happy". Maybe it does, but it surely keeps players confused.
- Setting "start" cargo levels actually sets the "end" levels, and
vice versa. Has always been broken that way.
- Predicting what exactly autonavigation will do at the update isn't
easy.
* The info pages documenting it amount to almost 400 non-blank lines
formatted. They claim only merchant ships can be given orders.
This is wrong. Unlikely to be the only error.
* Few players use it, and its workings at the update a fairly opaque.
Makes it a nice hidey-hole for bugs. Here are two:
- Unlike the scuttle command, autonavigation happily scuttles trade
ships while they're on the trading block.
- Unlike the load command, autonavigation can load in friendly and
allied sectors.
* It's more than 700 lines of rather crufty code nobody wants to
touch. Thanks to a big effort in Empire 2, it shares code with the
navigation command. It still duplicates load code. The sharing
complicates fixing the bugs demonstrated by navi-march-test.
Reviewing, fixing and testing this mess isn't worth the opportunity
cost. Remove it instead. Drop commands order, qorder and sorder.
Drop ship selectors xstart, xend, ystart, yend, cargostart, cargoend,
amtstart, amtend, autonav.
xdump ship sheds almost half its columns. struct shpstr shrinks, on
my system from 200 to 160 bytes.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Commit d94d269 combined them into unit_put(), but that has turned out
not to be useful. Split them again.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Some callers have to second-guess shp_check_nav() to figure out
whether CN_LANDLOCKED means "too big to fit into the canal" or "can't
go there at all".
Fix that by returning d_navigation. CN_LANDLOCKED becomes either
NAV_CANAL or NAV_NONE, CN_CONSTRUCTION becomes either NAV_02 or
NAV_60, and CN_NAVIGABLE becomes NAVOK.
The CN_NAVIGABLE, ... codes are now unused. Drop them.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
As long as symbol_by_value(), show_capab() and togg() support only
int, flags need to fit into int.
Not a problem in practice, because no machine capable of running
Empire has int narrower than 32 bits, and 32 bits suffice.
Some flags members are long instead of int: struct lchrstr member
l_flags, struct natstr member nat_flags, struct mchrstr member m_flags
are long. Waste of space on machines with long wider than int.
Change them to int.
Rearrange struct lchrstr and struct natstr to avoid holes.
Why upgrade? I'm not a lawyer, but here's my take on the differences
to version 2:
* Software patents: better protection against abuse of patents to
prevent users from exercising the rights under the GPL. I doubt
we'll get hit with a patent suit, but it's a good move just on
general principles.
* License compatibility: compatible with more free licenses, i.e. can
"steal" more free software for use in Empire. I don't expect to steal
much, but it's nice to have the option.
* Definition of "source code": modernization of some details for today's
networked world, to make it easier to distribute the software. Not
really relevant to us now, as we normally distribute full source code.
* Tivoization: this is about putting GPL-licensed software in hardware,
then make the hardware refuse to run modified software. "Neat" trick
to effectively deny its users their rights under the GPL. Abuse was
"pioneered" by TiVo (popular digital video recorders). GPLv3 forbids
it. Unlikely to become a problem for us.
* Internationalization: more careful wording, to harden the license
outside the US. The lawyers tell us it better be done that way.
* License violations: friendlier way to deal with license violations.
This has come out of past experience enforcing the GPL.
* Additional permissions: Probably not relevant to us.
Also include myself in the list of principal authors.
Oops when a stale copy is written back, i.e. the processor was yielded
since the copy was made. Such bugs are difficult to spot. Sequence
numbers catch them when they do actual harm (they also catch different
bugs). Generation numbers catch them even when they don't.
New ef_generation to count generations. Call new ef_make_stale() to
increment it whenever the processor may be yielded.
New struct emptypedstr member generation. To conserve space, make it
a bit-field of twelve bits, i.e. generations are only recorded modulo
2^12. Make sure all members of unit empobj_storage share it. It is
only used in copies; its value on disk and in the cache is
meaningless. Copies with generation other than ef_generation are
stale. Stale copies that are a multiple of 2^12 generations old can't
be detected, but that is sufficiently improbable.
Set generation to ef_generation by calling new ef_mark_fresh() when
making copies in ef_read() and ef_blank(). nav_ship() and
fltp_to_list() make copies without going through ef_read(), and
therefore need to call ef_mark_fresh() as well. Also call it in
obj_changed() to make check_sect_ok() & friends freshen their argument
when it is unchanged.
New must_be_fresh() oopses when its argument is stale. Call it in
ef_write() to catch write back of stale copies.
Store them and ef_type in bit-fields.
Allocate eight bits for ef_type. Values range from 0 to EF_GAME
(currently 16), so this is plenty.
Allocate twelve bits for sequence numbers. Sequence number mismatches
are now missed when the numbers are equal modulo 2^12. Still
sufficiently improbable.
Common machines store the bit-fields in a 32 bit word. There are
twelve bits left in that word for future use. Total savings 16 bits,
which is exactly what the previous commit spent on wider uids on
common machines.
Before, they were stored as short. Wider uids use more space, but the
next commit will recover it by narrowing other members.
The use of short has always limited the number of ships, planes, land
units and nukes to SHRT_MAX (commonly 32768). Only the most extreme
games ever came close.
Commit 49780e2c (v4.3.12) added struct sctstr member sct_uid to make
struct empobj member uid work for sectors. This made the limit apply
to sectors as well. We've had games with more than 32768 sectors.
Load counters are redundant; they can be computed from the carrier
uids. Keeping them up-to-date as the carriers change is a pain, and
we never got that quite complete.
Computing load counters straight from the carrier uids every time we
need them would be rather inefficient, but computing them from cargo
lists is not. So do that.
Remove the load counters: struct shpstr members shp_nplane,
shp_nchoppers, shp_nxlight, shp_nland, and struct lndstr members
lnd_nxlight and lnd_nland.
Don't compute/update load counters in build_ship(), build_land(),
land(), ldump(), load_plane_ship(), load_land_ship(),
load_plane_land(), load_land_land(), lstat(), sdump(), shi(), sstat(),
tend_land(), check_trade(), put_combat(), pln_oneway_to_carrier_ok),
pln_newlanding(), fit_plane_on_ship(), fit_plane_on_land(),
unit_list().
Nothing left in fit_plane_off_ship(), fit_plane_off_land(), so remove
them.
load_land_ship(), load_land_land(), check_trade(), pln_newlanding(),
put_plane_on_ship(), take_plane_off_ship(), put_plane_on_land(),
take_plane_off_land() no longer change the carrier, so don't put it.
Remove functions to recompute the load counters from carrier uids:
count_units(), lnd_count_units(), count_planes(), count_land_planes(),
pln_fixup() and lnd_fixup(), along with the latter two's private
copies of fit_plane_on_ship() and fit_plane_on_land().
New cargo list functions to compute load counts: unit_cargo_count()
and unit_nplane(), with convenience wrappers shp_nplane(),
shp_nland(), lnd_nxlight(), lnd_nland().
Use them to make ship selectors nplane, nchoppers, nxlight, nland
virtual. They now reflect what is loaded, not how the load uses the
available slots. This makes a difference when x-light planes or
choppers use plane slots.
Use them to make land unit selectors nxlight and nland virtual.
Use them to get load counts in land(), ldump(), load_plane_ship(),
load_land_ship(), load_plane_land(), load_land_land(), sdump(), shi(),
tend_land(), fit_plane_on_land(), trade_desc(), unit_list().
Rewrite fit_plane_on_ship() and could_be_on_ship() to use
shp_nplane(). could_be_on_ship() now takes load count arguments, as
computed by shp_nplane(), so it can be used for checking against an
existing load as well.
This oopses on output dependency violations, e.g. two threads doing a
read-modify-write without synchronization, or the one thread nesting
several read-modify-writes. Such bugs are difficult to spot, and tend
to be abusable. I figure we have quite a few of them.
New struct emptypedstr member seqno. Make sure all members of unit
empobj_storage share it. Initialize it in files: main() and
file_sct_init(). Set it in ef_blank() and new ef_set_uid() by calling
new get_seqno(). Use ef_set_uid() when copying objects: swaps(),
doland(), doship(), doplane(), dounit(), delete_old_news(). Step it
in ef_write() by calling new new_seqno().
Factor do_read() out of fillcache() to make it available for
get_seqno().
The abstract idea of tying ships and land units to a logistical tether
is sound, the concrete implementation as option FUEL is flawed. It
adds too much busy-work to the game to be enjoyable. It hasn't been
enabled in a public game for years. The code implementing it is ugly,
repetitive, and a burden to maintain.
Remove selector fuel from ship_ca[] and land_ca[], and selectors
fuelc, fuelu from mchr_ca[] and lchr_ca[]. Remove fields fuelc, fuelu
from ship.config and land.config.
Remove command fuel from player_coms[].
Deprecate edit key 'B' in doship(), dounit(), and don't show it in
pr_ship(), pr_land().
Drop opt_FUEL code from build_ship(), shi(), sdump(), ship_damage(),
show_ship_stats(), do_mob_ship(), nav_ship(), build_land(), land(),
ldump(), land_damage(), show_land_stats(), do_mob_land(),
resupply_all(), resupply_commod(), get_minimum(), has_supply(),
unit_list(), vers().
Remove opt_FUEL, fuel_mult, struct shpstr member shp_fuel, struct
mchrstr members m_fuelc and m_fuelu, M_OILER, struct lndstr member
lnd_fuel, struct lchrstr members l_fuelc and l_fuelu, fuel(), and
auto_fuel_ship().
Make sure all members of unit empobj_storage share it.
Add matching timestamp member to struct comstr, struct empobj, struct
gamestr, struct lonstr, struct natstr, struct nwsstr, struct trdstr,
struct trtstr. The timestamp isn't yet set for these. To be fixed.
Move the timestamp member to the right place in struct lndstr, struct
loststr, struct realmstr, struct nukstr, struct plnstr, struct sctstr,
struct shpstr.
This takes care of a number of bugs / inconsistencies:
* Submarines with zero mobility could interdict. Change to require
positive mobility.
* Submarines with zero firing range could not interdict. Fix by
dropping the test from perform_mission(). No ships in the stock
game are affected.
* Submarines without capability torp could fire return torpedoes and
interdict. Stock sbc, nm and msb were affected by the return fire
bug. Closes bug#950936.
* Shell resupply bugs: quiet_bigdef(), fire_torp() and
perform_mission() resupplied before checking all other requirements
and could thus get more shells than actually needed.
torp() no longer resupplies shells. It's hardly worth the bother, and
fire doesn't do it either.
This takes care of a number of bugs / inconsistencies:
* Ships with zero firing range could return fire and fire support, but
not fire actively or interdict. Fix by testing for gun limit
instead in multifire() and mission(). No ships in the stock game
are affected.
* Required gun crew was inconsistent: multifire() let N military fire
max(1,floor(N/2)) guns for active fire. Ditto perform_mission() for
interdiction. quiet_bigdef() let them fire N guns for returning gun
fire. Ditto sd() for firing support and firing at boarding parties.
fire_dchrg() let them fire floor(N/2) for returning fire to
torpedoes. Unify to let N military fire floor((N+1)/2) guns.
* Shell use was inconsistent: sd() and perform_mission() used one
shell per gun, everything else one per two guns. Unify to one shell
per two guns.
* Shell resupply bugs: multifire() got two shells regardless of actual
ammo use. quiet_bigdef() got one shell (but use_ammo() uses only
one, which is a bug). sd() and perform_mission() resupplied before
checking all other requirements and could thus get more shells than
actually needed.
Before 4.0.6, depth charges required no guns, one military, did damage
like shell fire from two guns, and used two shells. Missions were not
quite consistent with that (bug). 4.0.6 changed depth charges to work
exactly like shell fire (but without updating documentation
accordingly): require guns and gun crew, non-zero firing range, scale
damage and ammunition use with guns.
Go back to the old model, but with damage like three guns, to avoid
changing the stock game's dd now (three gun damage for two shells).
Stock game's af changes from two gun damage for one shell, and nas
from four gun damage for two shells.
Factor out common depth-charging code into shp_dchrg().
The macros defining unit stat development in tech are somewhat
inconvenient to use. Define more convenient functions, and hide away
the macros near the function definitions.
Make sure all members of unit empobj_storage share uid in addition to
ef_type.
Add matching uid member to struct gamestr, struct natstr and struct
sctstr, and set them.
Swap struct empobj members uid and own to make that easier, and update
struct comstr, struct lndstr, struct lonstr, struct loststr, struct
nwsstr, struct nukstr, struct plnstr, struct realmstr, struct shpstr,
struct trdstr, struct trtstr accordingly.
Note that the uid isn't properly set for struct nwsstr, struct lonstr,
struct trdstr, struct comstr and struct loststr. To be fixed.
(lndstr, plnstr, sctstr, shpstr): Change timestamp members lnd_access,
pln_access, sct_access, shp_access from real time (time_t) to ETUs
within a turn (short).
(land_ca, plane_ca, sect_ca, ship_ca): Update accordingly.
(build_ship, build_land, build_bridge, build_plane, build_tower)
(explore, check_trade, bsanct, takeover, takeover_ship)
(takeover_land): Use game_tick_to_now() instead of time() to update
the timestamp. Change check_trade(), takeover_ship(), takeover_land()
to do that only when MOB_ACCESS is enabled, for consistency.
(lupgr, supgr, pupgr, takeover_ship): Don't touch the timestamp where
mobility isn't touched either.
(sct_do_upd_mob, shp_do_upd_mob, lnd_do_upd_mob, pln_do_upd_mob): Use
game_tick_to_now() instead of increase_mob() to compute ETUs since
the timestamp and update the timestamp. Closes#1012699.
(increase_mob): Remove.
(mob_sect, mob_ship, mob_land, mob_plane): sct_do_upd_mob() & friends
no longer do the right thing at the update. Use game_reset_tick() and
pass its result directly to do_mob_sect() & friends. This is only
correct when argument is etu_per_update, which it always is. Remove
parameter. Callers changed.
(do_mob_sect, do_mob_ship, do_mob_land, do_mob_plane): Oops on
negative argument.
(mob_acc_globals, timestampfil, mobupdate, updating_mob)
(update_all_mob, timestamp_fixing, update_timestamps, mobility_check):
The mobupdate command was important to let deities manually
synchronize mobility updating with updates. That's no longer needed.
The code behind it is somewhat hairy and ugly, and updating it to work
with the Empire clock is just not worth it. Remove. Users changed.
(player_coms): Update accordingly.
(upda): Remove display of mobility updating state.
(mobility_init): No need to fix up mobility on startup, as the Empire
clock runs normally even when the server is down. Remove. Caller
changed.
other. Ensure headers in include/ can be included in any order
(except for econfig-spec.h, which is special). New header types.h to
help avoid inclusion cycles. Sort include directives. Remove some
superflous includes.
