We reject satellites, ABMs, anti-ship missiles, and SAMs. That's
enumerating badness. More robust replacement: accept only bomber,
tactical, cargo, except for anti-ship missiles.
Throw in PLN_LAUNCHED sanity checking while there.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
It happily arms a plane with a remote nuke. The nuke gets teleported
to the plane when the plane moves (a two-way sortie doesn't count as
move). Broken in 4.3.3. Reported by Harald Katzer.
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.
Replacing getrel(getnatp(US), THEM) by relations_with(US, THEM) makes
a difference only when US equals THEM. Replace in places where it's
obvious that they're not equal.
Note: getsect() sets player->owner to "player is god or owns this
sector". Thus, after getsect(..., §), sect.sct_own ==
player->cnum implies player->owner. Conversely, !player->owner
implies sect.sct_own != player->cnum. Similarly for getship(),
getplane() and nxtitem().
Before Empire 2, nukes could be delivered only with bomb (special
mission 'n', airburst only) and launch (targeting sectors or
satellites only).
Empire 2 made nukes available for any kind of bombing, and for any
missile strike on sectors or ships. This included interdiction and
support missions. Nuclear-tipped anti-sats and bomb mission n were
removed.
Unfortunately, this was done in a messy way, which led to
inconsistencies and bugs. The problem is that ordinary damage affects
just the target, while nuke damage affects an area. Code dealing with
plane damage was designed for the former. Instead of rewriting it to
cope with area damage cleanly, nuke damage got shoehorned into
pln_damage(), the function to compute conventional plane damage, as a
side effect: computing damage blasted sectors in the area.
If the plane carried a nuke, pln_damage() returned zero (conventional)
damage. Without further logic, this simply bypassed the code to apply
damage to the target. This worked out okay when the target already
got damaged correctly by the side effect.
However, some targets are immune to the side effect: when interdicting
a move or explore command, the commodities being moved are not in any
sector.
For other targets, damage has effects other than damaging the target:
offensive and defensive support don't apply the (conventional) damage
to the target sector. Instead, they turn it into a combat bonus.
Without further logic, nuclear damage doesn't contribute to that.
To make all that work, pln_damage() returned the nuclear damage for
ground zero as well. Because a plane does either conventional or
nuclear damage, one of them is always zero.
Most callers simply ignored the nuclear damage, and applied only the
conventional damage.
Bug: land units and ships failed to retreat when pin-bombed or
missiled with a nuke. That's because they received zero conventional
damage.
The mission code flies planes and missiles and tallies their damage.
This mission damage included nuclear damage at ground zero (except for
missiles sometimes, see below), to make support and commodity
interdiction work. Unfortunately, this broke other things.
Bug: when bombers interdicted ships or land units, nukes first damaged
the ships or land units by the side effect, then again through mission
damage. Interdicting missiles had a special case to avoid this.
Bug: when interdicting move, explore or transport, nukes first damaged
the sector by the side effect, then again through mission damage's
collateral damage.
There may well be more bugs hiding in this mess.
The mess is not worth fixing. While the idea of interdicting and
supporting with nukes sounds kind of cool, I believe it's pretty
irrelevant in actual play.
Instead, go back to a variation of the original rules: nukes can be
delivered only through bomb mission 's' and launch at sectors.
Make arm reject marine missiles in addition to satellites, ABMs and
SAMs, and clear the mission. Make mission reject planes armed with
nukes. Oops when they show up in mission_pln_equip() anyway.
Make pln_equip() allow planes with nukes only for missions 's' and
't'.
Clean up pln_damage() to just compute damage, without side effect.
Change strat_bomb() and launch_missile() to detonate nukes. Simplify
the other callers. Parameter mission of msl_launch_mindam() is now
unused, remove it.
Missiles exploding on launch no longer set off their nukes. That was
pretty ridiculous anyway.
Before, satellites could be disarmed and armed even in orbit. Nukes
on satellites went along into orbit, where they did nothing in
particular.
Nukes on ABMs and SAMs were lost without effect when their missile
intercepted.
The stock game is not affected, because its satellites, ABMs and SAMs
all have zero load.
pln_nuktype is redundant; it can be computed from the nuke's
nuk_plane.
Make plane selector nuketype virtual and NSC_EXTRA. It should have
been NSC_EXTRA all along. This changes xdump plane.
Don't set it in arm(), disarm(), build_plane(), pln_damage() and
nuk_fixup(). The latter no longer does anything, remove it.
Deprecate edit key 'n' in doplane(), and don't show it in pr_plane().
The key never made much sense.
eff_bomb(), comm_bomb(), ship_bomb(), plane_bomb(), land_bomb(),
strat_bomb(), mission_pln_equip(), air_damage(), msl_hit(),
pln_equip() tested pln_nuketype to check whether a plane carries a
nuke. Test nuk_on_plane() instead.
pdump(), plan(), trade_desc() print whether and what kind of nuke a
plane carries. Adapt that to use nuk_on_plane().
Failing a command with code RET_SYN prints help and doesn't charge
BTUs. Failing with code RET_FAIL doesn't print help and charges BTUs.
A couple of command failures were changed or added recently to fail
with RET_SYN, because they're due to invalid player input. Some of
them, however, can happen after the command already did something, so
BTUs must be charged, or else players can deliberately fail the
command to save BTUs:
* Commit 9eda5f87 adds RET_SYN failures when getting player input
fails for:
- arm third argument
- deliver fourth argument
- fire third argument
- lmine second argument
- order d fourth argument
- range second argument
- sail second argument
- tend third argument
* Commit be41e70f likewise for:
- designate second argument
- morale second argument
- set third argument
- tend fourth argument
* Commit d000bf92 likewise (with a bogus commit message) for bdes
second argument.
* Commit 9f4ce71a likewise for ltend third and fourth argument.
* Commit 9031b03b changes failure code from RET_FAIL when getting
player input fails for threshold third argument. It adds RET_SYN
failure when the argument is bad. Some bad arguments already failed
that way before.
* Commit a7cf69af changes it from RET_FAIL when designate second
argument is bad.
Change them all to fail with RET_FAIL.
Many other places have the same bug, but those are left for another
day.
The old code used getstarg() to get an argument with a different
prompt than snxtitem() uses, then passed the value to snxtitem()
unchecked. If the player aborts, getstarg() returns a null pointer,
and snxtitem() prompts again. Affected:
* load/lload plane/land third argument; load_plane_ship(),
load_land_ship(), load_plane_land(), load_land_land()
* bomb, drop, fly, paradrop, recon and sweep second argument;
get_planes()
* tend and ltend second and fourth argument; ltend(), tend(),
tend_land()
* mission second argument; mission()
Fix by making snxtitem() taking a prompt argument, null pointer
requests the old prompt.
Use that to simplify multifire() and torp(). Change the other callers
to pass NULL.
The old code didn't honor command abortion at the following prompts:
* arm third argument
* deliver fourth argument (also simplify)
* fire third argument
* fly and recon prompt for carrier to land on: pln_onewaymission()
treated abort like empty input, which made planes attempt landing in
the sector.
* lmine second argument
* order d fourth argument
* power c nat(s) argument
* range second argument
* sail second argument
* shutdown both arguments (first one was broken in commit 84cfd670,
v4.3.10, second one never worked).
* tend third argument
New pln_att(), pln_def(), pln_acc(), pln_range_max(), pln_load()
replace the struct plnstr members with the same names.
Make plane selectors att and def virtual.
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.
(nukstr): Hold one nuke instead of a stockpile: replace members nuk_n,
nuk_types by nuk_type, nuk_plane. Add nuk_land for completeness, like
nuk_ship it's not yet used.
(nuke_ca): Update accordingly: replace selectors number and types by
type and plane.
(build_nuke): Update accordingly.
(ndump, nuke): Update accordingly. Output is no longer sorted by
location, and nukes in same location no longer share id. nuke's extra
columns for nuclear plants are repeated for every nuke.
(trade_desc): Update accordingly.
(cede, grab_sect, check_nuke_ok, detonate, trade_nameof): Talk about
nukes instead of nuclear stockpiles.
(arm, disarm): Rewrite, split off new disarm(). Don't remove nuke
from the nuke file on arm. Allow usual plane syntax, not just plane
number. Change second argument from nuke type to nuke number. When
plane is already armed, ignore nuke argument and rearm (broken in
4.2.6).
(tran_nuke): Update for changed struct nukstr, make as similar as
possible to tran_plane. Change syntax to match transport plane.
(player_coms): Update arm, disarm and transport accordingly.
(prnuke, nuk_on_plane): New.
(nuk_add, nuk_delete): Stockpile management, remove.