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>
The capability to march land units spread over several sectors is
obscure and rarely useful. Accidental use is probably more frequent
than intentional use. Issues:
* Interactive prompts show only the leader's position, and give no
clue that some land units are actually elsewhere.
* Path finding is supported only when all marching land units are in
the same sector.
* In each step, the bmap is updated for the leader's radar. The bmap
is not updated around other marching land units. Already odd when
all units are in the leader's sector, and odder still when some are
elsewhere.
* Interdiction becomes rather complex. For each movement, every
sector entered is interdicted independently. This means the same
ship, land unit or plane can interdict multiple times. Interdiction
order depends on the order the code examines land units. 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 march.
I feel we're better off without this feature.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Unlike the move command, march checks sector abandonment before every
step.
If the player declines, the last land unit stays put and is removed
from the march.
Except when sectors or land units change while we're waiting for the
player's reply. Then the last unit is not removed from the march.
This can scatter land units. Screwed up when checking for abandoning
the sector was added in 4.2.2.
Change march to work like move, and to avoid scattering land units: if
the player declines to abandon the sector, the command simply fails.
Put the check into new lnd_abandon_askyn().
Extend would_abandon() and want_to_abandon() from a single land unit
to many. Rename the latter to abandon_askyn() for consistency.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
When attempting to enter a sector with a land unit that can't go there
while the marching land units are all in the same sector, march stops
and prompts without removing the incapable land unit from the group.
If another land unit has already entered the sector, the group becomes
scattered.
This can happen when marching a mixed group of spies and non-spies
into a non-allied sector. Same for marching a mixed group of trains
and non-trains into a sector without rail, except such groups have
been disallowed since commit 36e41e5 (v4.3.7). Both screwed up when
spies and trains were added in 4.0.0
Remove the incapable land unit from the group when another land unit
can enter the sector. This avoids scattering land units.
Don't remove incapable land units when no land unit can enter the
sector. Without this, march would remove everyone and end then.
It can also happen when sectors or land units change while we're
sitting at the "Do you really want to abandon X,Y" prompt. I'm going
to fix that differently.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
When attempting to enter a sector with a ship that can't go there
while the navigating ships are all in the same sector, navigate stops
and prompts without removing the incapable ship from the group. If
another ship has already entered the sector, the group becomes
scattered.
This can happen only when navigating a mixed group of ships with and
without canal capability into a canal. Broken in commit 74e4e281,
v4.3.0.
Remove the incapable ship from the group when another ship can enter
the sector. This avoids scattering ships.
Don't remove incapable ships when no ship can enter the sector.
Without this, navigate would remove everyone and end then.
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>
Does not cover scattered navigate and march, RAILWAYS 0, enemy action
while sitting at the prompt, and interdiction.
The test exposes bugs. They're marked "BUG:" in the test input.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
