Unit Option When Damaged Change Into Different Unit (Weakened Battleships)

redrum

@alkexr @Frostion As Cernel stated, it doesn't work if the unit is dies (out of hit points) as dying overrides the check to damaged changes into. This could probably be changed and shouldn't be too difficult though I probably won't have time this week.

@Cernel I consider doing remaining hit points rather than damaged but most existing properties check damage so decided to go with that for consistency.

@Hepps That can work though I believe you'd need a player enforced rule to ban taking the final hit point during casualty selection.

Hepps

@redrum Again while I haven't tested it.... the final hit point should be a moot point since once the unit hits the infrastructure level it should not be selectable as a casualty.

redrum

@Hepps Right but I think you can select multiple hit points in the same battle round casualty selection. So say I have a 2 HP unit that changes into infra at 1 damage, I could take 2 casualty hits in the same round and kill it rather than letting it change into the infra unit.

Hepps

@redrum Ah yes.

redrum

PR to allow it to work for units with 0 HP left: https://github.com/triplea-game/triplea/pull/4720

ron-murhammer created this issue in triplea-game/triplea

closed Allow whenHitPointsDamagedChangesInto to work for units with no HP left #4720

Frostion

That sounds great! How exactly will this work? When units run out of HP, do they leave the battle and change afterwards (the winner getting ownership) or do they change during battle (where original owner can hold on to the changing unit and maybe use it during battle)?

I can imagine both behaviours being nice and useful, but changing after battle would probably be more simple.

Looking forward to testing this when I have the time

Cernel

@redrum That is really a solid addition, I believe, as a number of times I wished it would be possible mostly to leave some left overs, as infrastructures, to be retained or captured by the side owning the territory in which the battle took place. I was thinking to actually open a feature request about it once I had a finished thing on which to actually apply it forthright. It makes me also think to an old game, called "Total Annihilation", in which when you killed the enemy units a quantity of the iron it was used in their production would remain on the field, to be added to your stock of it (tho this would not work very well here, as I suppose all the attacking turned units would be able to retreat, that would not make sense (same story if you would use this for upgrading units to veteran status out of enemy casualties)).

I see no issues if applied to defensive units only, and a possible application would be, for example, having "castle" units

that can be "killed" by "trebuchets" units,

but actually turning into damaged or downgraded versions of themselves.

(since a trebuchet should not be able to completely disintegrate a castle out of existence)

Will this immediately work for "air battles" too, right (and whatever case the unit would be preemptively removed, as well, like AA, subs and v2 naval bombardment)? For example, the trebuchets damaging castles would be good to have as an air battle before the regular battle. Would, then, the castles be turned for the regular battle, acting as per the abilities of the damaged/downgraded type, especially if they are supposed to make AA attacks?

Another question would be how about the retreat for these units? Will the new unit, that is made out of a damaged/killed attacking unit, retain the acquired possibilities and limits (for example, unable to retreat if originated out of an unloaded unit)?

Since the AA can kill a unit regardless of its hitpoints, will this work for such a case all the same as a unit reaching max damage by regular means (this needs to be documented)?

I also wonder regarding the case of AA flyover attacks? Would it be possible to leave another unit where the one was shot down (during a movement phase)?

Frostion

@Cernel and @redrum does
the whenHitPointsDamagedChangesInto work with both infrastructure damage points as well as normal unit HP (land/sea/air)?

Would be cool if it does. (And yes, I have not read this intire thread if it the answer should be here somewhere)

Edit: And is strategic bombing / damaging of infrastructure hit points still restricted to be done by air units?

Cernel

@Frostion It works only for hitpoints, but this doesn't exclude infrastructures. In the example above, castle units may be infrastructures damaged by AA attacks from trebuchets.

redrum

@Frostion The latter. The check of changes into is done at the end of each combat round. It now checks any damaged units and any units killed that round on whether they should change into a new unit.

It only works on normal unit HP not bombing damage. A similar mechanism could be added for bombing damage so could be a new feature request. I believe bombing damage can be done by non-air units but not positive.

@Cernel I don't believe changes into works for air battles as they have separate logic but haven't tested it. It should work for any part of a regular battle so AA, bombard, subs, etc.

I believe for retreating it will keep existing possibilities but won't have any unload limitations since its a new unit.

I believe it should work for AA that kill in one shot during normal battles.

I don't think it'll work for flyover or strat bombing AA as those aren't regular battles with combat rounds.

beelee

@redrum I know a lot of people have worked on this project over the years. You absolutely qualify for the triplea Hall of Fame. : ) Good Stuff !

Cernel

@redrum That retreat thing is a pretty major element, especially under default rules, in which if any of the units are unable to retreat, none can. It would at least need to be documented, as I don't think it may be expected.

redrum

@Cernel I did a basic retreat test and seemed like everything worked fine and it keeps the existing possibilities.

redrum

The changes to support this parameter for units with 0 HP has been merged. Please test out the latest pre-release and let me know if you have any issues.

Frostion

@Hepps @redrum
Total World War v3 has the following unit pictures:
germanBattleship
germanBattleship_hit
germanBattleship_hit1
germanBattleship_hit2

When and how exactly do the _hit1 and _hit2 images come into use? When are they used ingame to show the damaged unit?

When I try to implement multi HP units with more than one hit image, the engine seems to only want to use the single and normal _hit version, and not the numbered ones. A unit with 2 HP damage is just displayed on the map with the _hit picture supplemented by a black "2" number.

(Used the latest pre-release when testing)

Cernel

@Frostion Not up to me to answer, but I can only guess those images (hit1 and hit2) are not currently used by the game.

Cernel

Off topic, but I see a lossless compression thing run there. Any more info about it (in another topic)? How about a stickied topic with info on how to do that same process, in case other mapmakers may want to give a shot to it.

redrum

@Frostion I'm fairing certain those 2 images aren't used and just extras that @Hepps was testing with as alternatives. If you look at the germanCarrier images those so the normal images that are needed. There are only 2 images for each unit a normal one used when at full HP and a "_hit" one used if the unit has any HP damage.

The only way to achieve different unit images per amount of damage would be to use whenHitPointsDamagedChangesInto for each point of damage and have a different unit for each.

Cernel

@redrum There is a problem, using TripleA 2.0.16244.

I have this game code:

				<attachment name="unitAttachment" attachTo="wall" javaClass="games.strategy.triplea.attachments.UnitAttachment" type="unitType">
                         <option name="movement" value="0"/>
                         <option name="attack" value="0"/>
                         <option name="defense" value="0"/>
                         <option name="hitPoints" value="1"/>
                         <option name="whenHitPointsDamagedChangesInto" value="1:true:wall_breached"/>
                         <option name="requiresUnits" value="city"/>
                </attachment>
				
				<attachment name="unitAttachment" attachTo="wall_breached" javaClass="games.strategy.triplea.attachments.UnitAttachment" type="unitType">
                         <option name="isInfrastructure" value="true"/>
                         <option name="movement" value="0"/>
                         <option name="attack" value="0"/>
                         <option name="defense" value="0"/>
                         <option name="hitPoints" value="2"/>
                         <option name="whenHitPointsRepairedChangesInto" value="0:false:wall"/>
                </attachment>

All works fine, game-wise, and here it is the relevant history (tested by editing 99 Carthage warelephants in Roma):

Combat
Carthage creates battle in territory Roma
Battle in Roma
Carthage attack with 99 warelephants
RomanRepublic defend with 1 ballista, 1 city, 1 horseman, 2 legionarys, 2 leviss and 4 walls
RomanRepublic roll dice for 1 ballista in Roma, round 2 : 3
Carthage roll dice for 99 warelephants in Roma, round 2 : 6,3,5,6,2,1,5,5,4,1,6,5,4,6,5,6,3,2,6,5,3,5,3,6,6,1,4,4,1,4,2,5,5,5,4,4,6,4,6,3,6,5,3,2,5,2,6,2,1,6,3,4,1,3,1,6,4,6,3,2,5,4,1,5,2,4,2,4,4,4,5,1,4,1,2,2,4,3,5,4,3,3,2,6,5,1,5,2,3,3,6,2,3,5,1,1,4,6,4
RomanRepublic roll dice for 1 horseman, 2 legionarys, 2 leviss and 4 walls in Roma, round 2 : 1,5,1,4,1
Units damaged: 3 warelephants owned by the Carthage
4 walls owned by the RomanRepublic, 1 ballista owned by the RomanRepublic, 2 legionarys owned by the RomanRepublic, 2 leviss owned by the RomanRepublic and 1 horseman owned by the RomanRepublic lost in Roma
4 wall_breacheds owned by the RomanRepublic added in Roma
Carthage captures 19PUs while taking RomanRepublic capital
Carthage takes Roma from RomanRepublic
Carthage win
Battle casualty summary: Battle score (TUV change) for attacker is 27
Recording Battle Statistics
Non Combat Move
7 units repaired.
4 wall_breacheds owned by the Carthage removed in Roma
4 walls owned by the Carthage added in Roma

But I get the following error, when I conquer a territory after having removed all wall units, thus capturing them all as damaged wall_breached infrastructures, and repairing them at the start of the immediately subsequent non combat movement phase:

ott 19, 2019 9:00:05 AM org.triplea.game.client.HeadedGameRunner lambda$main$0
GRAVE: null
java.lang.NullPointerException
	at games.strategy.triplea.image.UnitImageFactory.getBaseImageUrl(UnitImageFactory.java:148)
	at games.strategy.triplea.image.UnitImageFactory.getBaseImageUrl(UnitImageFactory.java:142)
	at games.strategy.triplea.image.UnitImageFactory.getTransformedImage(UnitImageFactory.java:156)
	at games.strategy.triplea.image.UnitImageFactory.getImageDimensions(UnitImageFactory.java:306)
	at games.strategy.triplea.ui.unit.scroller.AvatarPanelFactory.createUnitStackImage(AvatarPanelFactory.java:79)
	at games.strategy.triplea.ui.unit.scroller.AvatarPanelFactory.buildPanel(AvatarPanelFactory.java:51)
	at games.strategy.triplea.ui.unit.scroller.UnitScroller.lambda$drawUnitAvatarPane$4(UnitScroller.java:167)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:776)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:727)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:746)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

Yet, everything in view seems working fine. The "wall", "wall_breached" and "wall_breached_hit" images are all in the "units" main folder (and not in the players subfolders). Am I correct I don't need a "wall_hit" unit, since the "wall" is 1 hitpoint changing when going down to 0 (removed)?

Moreover, this error happens only sometimes, under the exactly same after combat situation, beside only of a varying number of "warelephants" getting damaged, depending on dice results (that doesn't matter, as all are repaired for free on the same turn).

p.s.: Can I also get confirmed that what I'm doing is fine and meant to be supported, especially referring to changing a not infrastructure unit into a damaged infrastructure one?

Cernel

The game code could have been just this:

				<attachment name="unitAttachment" attachTo="wall" javaClass="games.strategy.triplea.attachments.UnitAttachment" type="unitType">
                         <option name="whenHitPointsDamagedChangesInto" value="1:true:wall_breached"/>
                         <option name="requiresUnits" value="city"/>
                </attachment>
				
				<attachment name="unitAttachment" attachTo="wall_breached" javaClass="games.strategy.triplea.attachments.UnitAttachment" type="unitType">
                         <option name="isInfrastructure" value="true"/>
                         <option name="hitPoints" value="2"/>
                         <option name="whenHitPointsRepairedChangesInto" value="0:false:wall"/>
                </attachment>