Resolved #2588 - instead of tile ownershp being transferrable between cities, cities can now work tiles belonging to other cities.

android/assets/GameSettings_.json

@@ -1 +0,0 @@
-{checkForDueUnits:false,tutorialsShown:[Injured_Units,Roads_and_Railroads,Happiness,Enemy_City,Golden_Age,_OtherCivEncountered,Strategic_Resource,Siege_Units,City_Expansion,Apollo_Program,Embarking,Tile_Clicked,Culture_and_Policies,_EnemyCityNeedsConqueringWithMeleeUnit,Introduction,Workers,Luxury_Resource,_BarbarianEncountered,_Slow_Start,Cities,Slow_Start,Unhappiness,Contact_Me],tutorialTasksCompleted:[See your stats breakdown,Found city,Enter city screen,Open the options table,Create a trade route,Conquer a city,Pick construction,Move an air unit,Pick technology,Move unit,Meet another civilization,Reassign worked tiles,Pass a turn,Construct an improvement],soundEffectsVolume:0,musicVolume:0,showTutorials:false,showPixelUnits:true,userId:b4565c3f-c349-446e-a013-909b6e73fb89,windowState:{width:1920,height:986}}

core/src/com/unciv/logic/city/CityInfo.kt

@@ -528,18 +528,6 @@ class CityInfo {
         tryUpdateRoadStatus()
     }
 
-    // Acquiring in this context means transferring ownership to another city of the same civ
-    fun canAcquireTile(newTileInfo: TileInfo): Boolean {
-        val owningCity = newTileInfo.getCity()
-        if (owningCity!=null && owningCity!=this
-                && newTileInfo.getOwner()!!.isCurrentPlayer()
-                && newTileInfo.aerialDistanceTo(getCenterTile()) <= 3
-                && newTileInfo.neighbors.any{it.getCity()==this}) {
-            return true
-        }
-        return false
-    }
-
     private fun tryUpdateRoadStatus(){
         if(getCenterTile().roadStatus==RoadStatus.None){
             val roadImprovement = getRuleset().tileImprovements["Road"]

core/src/com/unciv/ui/cityscreen/CityScreenTileTable.kt

@@ -2,12 +2,10 @@ package com.unciv.ui.cityscreen
 
 import com.badlogic.gdx.graphics.Color
 import com.badlogic.gdx.scenes.scene2d.ui.Table
-import com.badlogic.gdx.scenes.scene2d.ui.TextButton
 import com.unciv.UncivGame
 import com.unciv.logic.map.TileInfo
 import com.unciv.models.UncivSound
 import com.unciv.models.stats.Stats
-import com.unciv.models.translations.tr
 import com.unciv.ui.utils.*
 import kotlin.math.roundToInt
 
@@ -52,13 +50,10 @@ class CityScreenTileTable(val cityScreen: CityScreen): Table(){
             innerTable.add(buyTileButton).row()
             innerTable.add("You have [${city.civInfo.gold}] gold".toLabel(Color.YELLOW, 16)).padTop(2f)
         }
-        if(city.canAcquireTile(selectedTile)) {
-            val acquireTileButton = "Acquire".toTextButton()
-            acquireTileButton.onClick {
-                city.expansion.takeOwnership(selectedTile)
-                UncivGame.Current.setScreen(CityScreen(city))
-            }
-            innerTable.add(acquireTileButton).row()
+
+        if(city.civInfo.cities.filterNot { it==city }
+                        .any { it.workedTiles.contains(selectedTile.position) }) {
+            innerTable.add("Worked by [${selectedTile.getCity()!!.name}]".toLabel()).row()
         }
 
         if(city.workedTiles.contains(selectedTile.position)){

core/src/com/unciv/ui/cityscreen/CityTileGroup.kt

@@ -30,11 +30,9 @@ class CityTileGroup(private val city: CityInfo, tileInfo: TileInfo, tileSetStrin
 
         // this needs to happen on update, because we can buy tiles, which changes the definition of the bought tiles...
         when {
-            tileInfo.getCity()!=city -> { // outside of city
+            tileInfo.getOwner()!=city.civInfo -> { // outside of civ boundary
                 baseLayerGroup.color.a = 0.3f
                 yieldGroup.isVisible = false
-                if (city.canAcquireTile(tileInfo))
-                    icons.addPopulationIcon(ImageGetter.getStatIcon("Acquire"))
             }
 
             tileInfo !in city.tilesInRange -> { // within city but not close enough to be workable
@@ -42,6 +40,12 @@ class CityTileGroup(private val city: CityInfo, tileInfo: TileInfo, tileSetStrin
                 baseLayerGroup.color.a = 0.5f
             }
 
+            city.civInfo.cities.filterNot { it==city } // worked by another city
+                    .any { it.workedTiles.contains(tileInfo.position) } -> {
+                // Don't fade out, but don't add a population icon either.
+            }
+
+
             tileInfo.isLocked() -> {
                 icons.addPopulationIcon(ImageGetter.getImage("OtherIcons/Lock"))
             }
@@ -70,7 +74,7 @@ class CityTileGroup(private val city: CityInfo, tileInfo: TileInfo, tileSetStrin
         yieldGroup.centerX(this)
         yieldGroup.y= height * 0.25f - yieldGroup.height / 2
 
-        if (tileInfo.isWorked() || city.canAcquireTile(tileInfo)) {
+        if (tileInfo.isWorked()) {
             yieldGroup.color = Color.WHITE
         }
         else if(!tileInfo.isCityCenter()){
@@ -85,7 +89,7 @@ class CityTileGroup(private val city: CityInfo, tileInfo: TileInfo, tileSetStrin
             populationIcon.setPosition(width / 2 - populationIcon.width / 2,
                     height * 0.85f - populationIcon.height / 2)
 
-            if (tileInfo.isWorked() || city.canAcquireTile(tileInfo)) {
+            if (tileInfo.isWorked()) {
                 populationIcon.color = Color.WHITE
             }
             else if(!tileInfo.isCityCenter()){

core/src/com/unciv/ui/tilegroups/TileGroup.kt

@@ -241,21 +241,21 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
         val identifier = tileBaseImageLocations.joinToString(";")
         if (identifier == tileImagesIdentifier) return
 
-        for(image in tileBaseImages) image.remove()
+        for (image in tileBaseImages) image.remove()
         tileBaseImages.clear()
-        for(location in tileBaseImageLocations.reversed()) { // reversed because we send each one to back
+        for (location in tileBaseImageLocations.reversed()) { // reversed because we send each one to back
             // Here we check what actual tiles exist, and pick one - not at random, but based on the tile location,
             // so it stays consistent throughout the game
             val existingImages = ArrayList<String>()
             existingImages.add(location)
-            var i=2
-            while (true){
-                val tileVariant = location+i
-                if(ImageGetter.imageExists(location+i)) existingImages.add(tileVariant)
+            var i = 2
+            while (true) {
+                val tileVariant = location + i
+                if (ImageGetter.imageExists(tileVariant)) existingImages.add(tileVariant)
                 else break
-                i+=1
+                i += 1
             }
-            val finalLocation = existingImages.random(Random(tileInfo.position.hashCode()+location.hashCode()))
+            val finalLocation = existingImages.random(Random(tileInfo.position.hashCode() + location.hashCode()))
 
             val image = ImageGetter.getImage(finalLocation)
             tileBaseImages.add(image)
@@ -268,7 +268,7 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
 
     fun showMilitaryUnit(viewingCiv: CivilizationInfo) = showEntireMap
             || viewingCiv.viewableInvisibleUnitsTiles.contains(tileInfo)
-            || (!tileInfo.hasEnemySubmarine(viewingCiv))
+            || !tileInfo.hasEnemySubmarine(viewingCiv)
 
     fun isViewable(viewingCiv: CivilizationInfo) = showEntireMap
             || viewingCiv.viewableTiles.contains(tileInfo)