Implemented religious pressure (#4863)

* Implemented religious pressure: cities now can have more than one religion in them and religions spread between nearby cities over time.

* Implemented proposed changes

* Implemented requested changes & minor changes I forgot to include last time

* All pantheons not founded by you are now removed when you gain a new city (found this somewhere in the source code of the original, don't know if it's documented anywhere online)

android/assets/jsons/Civ V - Vanilla/Units.json

@@ -1500,8 +1500,10 @@
 		"name": "Great Prophet",
 		"unitType": "Civilian",
 		"uniques": ["Can construct [Holy site] if it hasn't spread religion yet", "Can spread religion [4] times",
-			"May found a religion", "Great Person - [Faith]", "Unbuildable", "Religious Unit", "Hidden when religion is disabled"],
-		"movement": 2
+			"May found a religion", "May enter foreign tiles without open borders", "[-1] Visibility Range",
+			"Great Person - [Faith]", "Unbuildable", "Religious Unit", "Hidden when religion is disabled"],
+		"movement": 2,
+		"religiousStrength": 1000
 	},
 	{
 		"name": "Great General",
@@ -1525,9 +1527,11 @@
 	{
 		"name": "Missionary",
 		"unitType": "Civilian",
-		"uniques": ["Can spread religion [2] times", "Can be purchased with [Faith] [in all cities in which the majority religion is a major religion]",
-			"Unbuildable", "Religious Unit", "Hidden when religion is disabled"],
-		"movement": 4
+		"uniques": ["Can spread religion [2] times", "May enter foreign tiles without open borders, but loses [250] religious strength each turn it ends there",
+			"Can be purchased with [Faith] [in all cities in which the majority religion is a major religion]", 
+			"[-1] Visibility Range", "Unbuildable", "Religious Unit", "Hidden when religion is disabled"],
+		"movement": 4,
+		"religiousStrength": 1000
 	}
 
 	/* Spaceship Parts */

android/assets/jsons/translations/template.properties

@@ -533,6 +533,7 @@ Our influence with City-States has started dropping faster! =
 You gained [Stats] as your religion was spread to [cityName] = 
 You gained [Stats] as your religion was spread to an unknown city = 
 Your city [cityName] was converted to [religionName]! = 
+Your [unitName] lost its faith after spending too long inside enemy territory! = 
 
 
 # World Screen UI 

core/src/com/unciv/Constants.kt

@@ -63,6 +63,9 @@ object Constants {
     const val unitActionParadrop = "Paradrop"
 
     const val futureTech = "Future Tech"
+    // Easter egg name. Hopefully is to hopefully avoid conflicts when later players can name their own religions.
+    // This religion name should never be displayed.
+    const val noReligionName = "The religion of TheLegend27" 
 
     const val cancelImprovementOrder = "Cancel improvement order"
     const val tutorialPopupNamePrefix = "Tutorial: "

core/src/com/unciv/logic/GameInfo.kt

@@ -91,7 +91,7 @@ class GameInfo {
     fun getCurrentPlayerCivilization() = currentPlayerCiv
     fun getBarbarianCivilization() = getCivilization(Constants.barbarians)
     fun getDifficulty() = difficultyObject
-    fun getCities() = civilizations.flatMap { it.cities }
+    fun getCities() = civilizations.asSequence().flatMap { it.cities }
     fun getAliveCityStates() = civilizations.filter { it.isAlive() && it.isCityState() }
     fun getAliveMajorCivs() = civilizations.filter { it.isAlive() && it.isMajorCiv() }
     //endregion

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

@@ -485,7 +485,8 @@ class CityInfo {
             }
         } else population.nextTurn(foodForNextTurn())
 
-        // if (civInfo.gameInfo.hasReligionEnabled()) religion.getAffectedBySurroundingCities()
+        // This should go after the population change, as that might impact the amount of followers in this city
+        if (civInfo.gameInfo.hasReligionEnabled()) religion.endTurn()
 
         if (this in civInfo.cities) { // city was not destroyed
             health = min(health + 20, getMaxHealth())
@@ -652,7 +653,7 @@ class CityInfo {
     }
 
     fun isHolyCity(): Boolean {
-        return civInfo.gameInfo.religions.values.any { it.holyCityId == id } 
+        return religion.religionThisIsTheHolyCityOf != null 
     }
     
     fun canBeDestroyed(): Boolean {

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

@@ -215,6 +215,8 @@ class CityInfoConquestFunctions(val city: CityInfo){
                     cityConstructions.addBuilding(civEquivalentBuilding.name)
                 }
             }
+            
+            religion.removeUnknownPantheons()
 
             tryUpdateRoadStatus()
         }

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

@@ -1,11 +1,10 @@
 package com.unciv.logic.city
 
-import com.unciv.logic.civilization.CivilizationInfo
+import com.unciv.Constants
 import com.unciv.logic.civilization.NotificationIcon
 import com.unciv.models.Counter
+import com.unciv.models.metadata.GameSpeed
 import com.unciv.models.ruleset.Unique
-import com.unciv.models.stats.Stats
-import kotlin.math.roundToInt
 
 class CityInfoReligionManager {
     @Transient
@@ -16,16 +15,41 @@ class CityInfoReligionManager {
     val religionsAtSomePointAdopted: HashSet<String> = hashSetOf()
 
     private val pressures: Counter<String> = Counter()
+    // `getNumberOfFollowers()` was called a surprisingly large amount of time, so caching it feels useful
+    @Transient
+    private val followers: Counter<String> = Counter()
+    
+    private val pressureFromAdjacentCities: Int by lazy {
+        when (cityInfo.civInfo.gameInfo.gameParameters.gameSpeed) {
+            GameSpeed.Quick -> 9
+            GameSpeed.Standard -> 6
+            GameSpeed.Epic -> 4
+            GameSpeed.Marathon -> 2
+        }
+    }
+    
+    var religionThisIsTheHolyCityOf: String? = null 
+    
+    init {
+        clearAllPressures()
+    }
     
     fun clone(): CityInfoReligionManager {
         val toReturn = CityInfoReligionManager()
         toReturn.religionsAtSomePointAdopted.addAll(religionsAtSomePointAdopted)
         toReturn.pressures.putAll(pressures)
+        toReturn.followers.putAll(followers)
+        toReturn.religionThisIsTheHolyCityOf = religionThisIsTheHolyCityOf
         return toReturn
     }
     
     fun setTransients(cityInfo: CityInfo) {
         this.cityInfo = cityInfo
+        updateNumberOfFollowers()
+    }
+    
+    fun endTurn() {
+        getAffectedBySurroundingCities()
     }
     
     fun getUniques(): Sequence<Unique> {
@@ -40,14 +64,31 @@ class CityInfoReligionManager {
     
     fun clearAllPressures() {
         pressures.clear()
+        // We add pressure for following no religion
+        // Basically used as a failsafe so that there is always some religion, 
+        // and we don't suddenly divide by 0 somewhere
+        // Should be removed when updating the followers so it never becomes the majority religion, 
+        // `null` is used for that instead.
+        pressures.add(Constants.noReligionName, 100)
     }
     
-    fun addPressure(religionName: String, amount: Int) {
-        val oldMajorityReligion = getMajorityReligion()
+    fun addPressure(religionName: String, amount: Int, shouldUpdateFollowers: Boolean = true) {
         pressures.add(religionName, amount)
-        val newMajorityReligion = getMajorityReligion()
-        if (oldMajorityReligion != newMajorityReligion && newMajorityReligion != null) {
-            triggerReligionAdoption(newMajorityReligion)
+        
+        if (shouldUpdateFollowers) {
+            updateNumberOfFollowers()
+        }
+    }
+    
+    fun updatePressureOnPopulationChange(populationChangeAmount: Int) {
+        val majorityReligion =
+            if (getMajorityReligion() != null) getMajorityReligion()!!
+            else Constants.noReligionName
+        
+        if (populationChangeAmount > 0) {
+            addPressure(majorityReligion, 100 * populationChangeAmount)
+        } else {
+            updateNumberOfFollowers()
         }
     }
 
@@ -80,50 +121,94 @@ class CityInfoReligionManager {
         religionsAtSomePointAdopted.add(newMajorityReligion)
     }
     
+    private fun updateNumberOfFollowers() {
+        val oldMajorityReligion = getMajorityReligion()
+        
+        followers.clear()
+
+        val remainders = HashMap<String, Float>()
+        val pressurePerFollower = pressures.values.sum() / cityInfo.population.population
+
+        // First give each religion an approximate share based on pressure
+        for ((religion, pressure) in pressures) {
+            val followersOfThisReligion = (pressure.toFloat() / pressurePerFollower).toInt()
+            followers.add(religion, followersOfThisReligion)
+            remainders[religion] = pressure.toFloat() - followersOfThisReligion * pressurePerFollower
+        }
+
+        var unallocatedPopulation = cityInfo.population.population - followers.values.sum()
+
+        // Divide up the remaining population
+        while (unallocatedPopulation > 0) {
+            val largestRemainder = remainders.maxByOrNull { it.value }
+            if (largestRemainder == null) {
+                followers.add(Constants.noReligionName, unallocatedPopulation)
+                break
+            }
+            followers.add(largestRemainder.key, 1)
+            remainders[largestRemainder.key] = 0f
+            unallocatedPopulation -= 1
+        }
+        
+        followers.remove(Constants.noReligionName)
+
+        val newMajorityReligion = getMajorityReligion()
+        if (oldMajorityReligion != newMajorityReligion && newMajorityReligion != null) {
+            triggerReligionAdoption(newMajorityReligion)
+        }
+    }
+    
     fun getNumberOfFollowers(): Counter<String> {
-        val totalInfluence = pressures.values.sum()
-        val population = cityInfo.population.population
-        if (totalInfluence > 100 * population) {
-            val toReturn = Counter<String>()
-            for ((key, value) in pressures)
-                if (value > 100)
-                    toReturn.add(key, value / 100)
-            return toReturn
+        
+        // println(followers) // ToDo: remove this when a UI for viewing followers is added
+        
+        return followers
+    }
+    
+    /** Removes all pantheons except for the one founded by the current owner of the city
+     *  Should be called whenever a city changes hands, e.g. conquering and trading
+     */
+    fun removeUnknownPantheons() {
+        for (pressure in pressures) {
+            val correspondingReligion = cityInfo.civInfo.gameInfo.religions[pressure.key]!!
+            if (correspondingReligion.isPantheon() 
+                && correspondingReligion.foundingCivName != cityInfo.civInfo.civName
+            ) {
+                pressures.remove(pressure.key)
+            }
         }
-
-        val toReturn = Counter<String>()
-
-        for ((key, value) in pressures) {
-            val percentage = value.toFloat() / totalInfluence
-            val relativePopulation = (percentage * population).roundToInt()
-            toReturn.add(key, relativePopulation)
-        }
-        return toReturn
+        updateNumberOfFollowers()
     }
 
     fun getMajorityReligion(): String? {
         val followersPerReligion = getNumberOfFollowers()
         if (followersPerReligion.isEmpty()) return null
         val religionWithMaxFollowers = followersPerReligion.maxByOrNull { it.value }!!
-        return if (religionWithMaxFollowers.value >= cityInfo.population.population) religionWithMaxFollowers.key
+        return if (religionWithMaxFollowers.value >= cityInfo.population.population / 2) religionWithMaxFollowers.key
         else null
     }
 
-    fun getAffectedBySurroundingCities() {
+    private fun getAffectedBySurroundingCities() {
+        // We don't update the amount of followers yet, as only the end result should matter
+        // If multiple religions would become the majority religion due to pressure, 
+        // this will make it so we only receive a notification for the last one.
+        // Also, doing it like this increases performance :D
+        if (cityInfo.isHolyCity()) {
+            addPressure(religionThisIsTheHolyCityOf!!,5 * pressureFromAdjacentCities, false)
+        }
+        
         val allCitiesWithin10Tiles =
-            cityInfo.civInfo.gameInfo.civilizations.asSequence().flatMap { it.cities }
+            cityInfo.civInfo.gameInfo.getCities()
                 .filter {
-                    it != cityInfo && it.getCenterTile()
-                        .aerialDistanceTo(cityInfo.getCenterTile()) <= 10
+                    it != cityInfo 
+                    && it.getCenterTile().aerialDistanceTo(cityInfo.getCenterTile()) <= 10
                 }
         for (city in allCitiesWithin10Tiles) {
-            val majorityReligionOfCity = city.religion.getMajorityReligion()
-            if (majorityReligionOfCity == null) continue
-            else addPressure(
-                majorityReligionOfCity, 
-                if (city.isHolyCity()) 30
-                else 6
-            ) 
+            val majorityReligionOfCity = city.religion.getMajorityReligion() ?: continue
+            if (!cityInfo.civInfo.gameInfo.religions[majorityReligionOfCity]!!.isMajorReligion()) continue
+            addPressure(majorityReligionOfCity, pressureFromAdjacentCities, false) 
         }
+        
+        updateNumberOfFollowers()
     }
 }

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

@@ -56,7 +56,7 @@ class PopulationManager {
         if (food < 0)
             cityInfo.civInfo.addNotification("[${cityInfo.name}] is starving!", cityInfo.location, NotificationIcon.Growth, NotificationIcon.Death)
         if (foodStored < 0) {        // starvation!
-            if (population > 1) population--
+            if (population > 1) addPopulation(-1)
             foodStored = 0
         }
         if (foodStored >= getFoodToNextPopulation()) {  // growth!
@@ -68,7 +68,7 @@ class PopulationManager {
             // Try to avoid runaway food gain in mods, just in case 
             if (percentOfFoodCarriedOver > 95) percentOfFoodCarriedOver = 95 
             foodStored += (getFoodToNextPopulation() * percentOfFoodCarriedOver / 100f).toInt()
-            population++
+            addPopulation(1)
             autoAssignPopulation()
             cityInfo.civInfo.addNotification("[${cityInfo.name}] has grown!", cityInfo.location, NotificationIcon.Growth)
         }
@@ -77,14 +77,18 @@ class PopulationManager {
     private fun getStatsOfSpecialist(name: String) = cityInfo.cityStats.getStatsOfSpecialist(name)
 
     internal fun addPopulation(count: Int) {
-        population += count
-        if (population < 0) population = 0
+        val changedAmount = 
+            if (population + count < 0) -population
+            else count
+        population += changedAmount
         val freePopulation = getFreePopulation()
         if (freePopulation < 0) {
             unassignExtraPopulation()
         } else {
             autoAssignPopulation()
         }
+        
+        cityInfo.religion.updatePressureOnPopulationChange(changedAmount)
     }
     
     internal fun setPopulation(count: Int) {

core/src/com/unciv/logic/civilization/CapitalConnectionsFinder.kt

@@ -32,7 +32,7 @@ class CapitalConnectionsFinder(private val civInfo: CivilizationInfo) {
         // this is so we know that if we've seen which cities can be connected by port A, and one
         // of those is city B, then we don't need to check the cities that B can connect to by port,
         // since we'll get the same cities we got from A, since they're connected to the same sea.
-        while (citiesToCheck.isNotEmpty() && citiesReachedToMediums.size < allCivCities.size) {
+        while (citiesToCheck.isNotEmpty() && citiesReachedToMediums.size < allCivCities.count()) {
             newCitiesToCheck = mutableListOf()
             for (cityToConnectFrom in citiesToCheck) {
                 if (cityToConnectFrom.containsHarbor()) {

core/src/com/unciv/logic/civilization/ReligionManager.kt

@@ -87,9 +87,8 @@ class ReligionManager {
         religion = Religion(belief.name, civInfo.gameInfo, civInfo.civName)
         religion!!.followerBeliefs.add(belief.name)
         civInfo.gameInfo.religions[belief.name] = religion!!
-        // ToDo: This should later be changed when religions can have multiple beliefs
-        civInfo.getCapital().religion.clearAllPressures()
-        civInfo.getCapital().religion.addPressure(belief.name, 100) // Capital is religious, other cities are not
+        for (city in civInfo.cities)
+            city.religion.addPressure(belief.name, 200 * city.population.population) 
         religionState = ReligionState.Pantheon
     }
     
@@ -114,10 +113,9 @@ class ReligionManager {
 
         if (Random(civInfo.gameInfo.turns).nextFloat() < prophetSpawnChange) {
             val birthCity =
-                if (religionState == ReligionState.Pantheon) civInfo.getCapital()
-                else civInfo.cities.firstOrNull { it.id == religion!!.holyCityId }
-            val prophet = civInfo.addUnit("Great Prophet", birthCity)
-            if (prophet == null) return
+                if (religionState <= ReligionState.Pantheon) civInfo.getCapital()
+                else civInfo.cities.firstOrNull { it.religion.religionThisIsTheHolyCityOf == religion!!.name }
+            val prophet = civInfo.addUnit("Great Prophet", birthCity) ?: return
             prophet.religion = religion!!.name
             prophet.abilityUsedCount["Religion Spread"] = 0
             storedFaith -= faithForNextGreatProphet()
@@ -170,15 +168,14 @@ class ReligionManager {
         }
         newReligion.followerBeliefs.addAll(followerBeliefs)
         newReligion.founderBeliefs.addAll(founderBelief)
-        newReligion.holyCityId = foundingCityId
         religion = newReligion
         civInfo.gameInfo.religions[name] = newReligion
 
         religionState = ReligionState.Religion
-        val holyCity = civInfo.cities.firstOrNull { it.id == newReligion.holyCityId }!!
-        // ToDo: check this when implementing followers
-        holyCity.religion.clearAllPressures()
-        holyCity.religion.addPressure(name, 100)
+
+        val holyCity = civInfo.cities.first { it.id == foundingCityId }
+        holyCity.religion.religionThisIsTheHolyCityOf = newReligion.name
+        holyCity.religion.addPressure(name, holyCity.population.population * 500)
 
         foundingCityId = null
     }

core/src/com/unciv/logic/map/MapUnit.kt

@@ -71,6 +71,9 @@ class MapUnit {
     @Transient
     var cannotEnterOceanTilesUntilAstronomy = false
 
+    @Transient
+    var canEnterForeignTerrain: Boolean = false
+    
     @Transient
     var paradropRange = 0
 
@@ -95,7 +98,7 @@ class MapUnit {
     fun displayName(): String {
         val name = if (instanceName == null) name
                    else "$instanceName ({${name}})"
-        return if (religion != null && maxReligionSpreads() > 0) "[$name] ([$religion])"
+        return if (religion != null) "[$name] ([$religion])"
                else name
     }
 
@@ -113,6 +116,7 @@ class MapUnit {
     
     var abilityUsedCount: HashMap<String, Int> = hashMapOf()
     var religion: String? = null
+    var religiousStrengthLost = 0
     
     //region pure functions
     fun clone(): MapUnit {
@@ -130,6 +134,7 @@ class MapUnit {
         toReturn.isTransported = isTransported
         toReturn.abilityUsedCount.putAll(abilityUsedCount)
         toReturn.religion = religion
+        toReturn.religiousStrengthLost = religiousStrengthLost
         return toReturn
     }
 
@@ -177,7 +182,7 @@ class MapUnit {
         val uniques = ArrayList<Unique>()
         val baseUnit = baseUnit()
         uniques.addAll(baseUnit.uniqueObjects)
-        if (type != null) uniques.addAll(type!!.uniqueObjects)
+        uniques.addAll(type.uniqueObjects)
         
         for (promotion in promotions.promotions) {
             uniques.addAll(currentTile.tileMap.gameInfo.ruleSet.unitPromotions[promotion]!!.uniqueObjects)
@@ -193,12 +198,14 @@ class MapUnit {
         ignoresTerrainCost = hasUnique("Ignores terrain cost")
         roughTerrainPenalty = hasUnique("Rough terrain penalty")
         doubleMovementInCoast = hasUnique("Double movement in coast")
-        doubleMovementInForestAndJungle =
-            hasUnique("Double movement rate through Forest and Jungle")
+        doubleMovementInForestAndJungle = hasUnique("Double movement rate through Forest and Jungle")
         doubleMovementInSnowTundraAndHills = hasUnique("Double movement in Snow, Tundra and Hills")
         canEnterIceTiles = hasUnique("Can enter ice tiles")
         cannotEnterOceanTiles = hasUnique("Cannot enter ocean tiles")
         cannotEnterOceanTilesUntilAstronomy = hasUnique("Cannot enter ocean tiles until Astronomy")
+        canEnterForeignTerrain = 
+            hasUnique("May enter foreign tiles without open borders, but loses [] religious strength each turn it ends there")
+            || hasUnique("May enter foreign tiles without open borders")
     }
 
     fun hasUnique(unique: String): Boolean {
@@ -239,7 +246,9 @@ class MapUnit {
         for (unique in getTile().getAllTerrains().flatMap { it.uniqueObjects })
             if (unique.placeholderText == "[] Sight for [] units" && matchesFilter(unique.params[1]))
                 visibilityRange += unique.params[0].toInt()
-
+        
+        if (visibilityRange < 1) visibilityRange = 1
+        
         return visibilityRange
     }
 
@@ -619,6 +628,23 @@ class MapUnit {
 
         if (action == Constants.unitActionParadrop)
             action = null
+        
+        if (hasUnique("Religious Unit") 
+            && getTile().getOwner() != null 
+            && !getTile().getOwner()!!.isCityState() 
+            && !civInfo.canPassThroughTiles(getTile().getOwner()!!)
+        ) {
+            val lostReligiousStrength =
+                getMatchingUniques("May enter foreign tiles without open borders, but loses [] religious strength each turn it ends there")
+                    .map { it.params[0].toInt() }
+                    .minOrNull()
+            if (lostReligiousStrength != null)
+                religiousStrengthLost += lostReligiousStrength
+            if (religiousStrengthLost >= baseUnit.religiousStrength) {
+                civInfo.addNotification("Your [${name}] lost its faith after spending too long inside enemy territory!", getTile().position, name)
+                destroy()
+            }
+        }
 
         getCitadelDamage()
         getTerrainDamage()
@@ -653,7 +679,7 @@ class MapUnit {
             action = null
 
         val tileOwner = getTile().getOwner()
-        if (tileOwner != null && !civInfo.canPassThroughTiles(tileOwner) && !tileOwner.isCityState()) // if an enemy city expanded onto this tile while I was in it
+        if (tileOwner != null && !canEnterForeignTerrain && !civInfo.canPassThroughTiles(tileOwner) && !tileOwner.isCityState()) // if an enemy city expanded onto this tile while I was in it
             movement.teleportToClosestMoveableTile()
     }
 
@@ -914,6 +940,14 @@ class MapUnit {
         return getMatchingUniques("Can spread religion [] times").sumBy { it.params[0].toInt() }
     }
     
+    fun canSpreadReligion(): Boolean {
+        return hasUnique("Can spread religion [] times")
+    }
+    
+    fun getPressureAddedFromSpread(): Int {
+        return baseUnit.religiousStrength
+    }
+    
     fun getReligionString(): String {
         val maxSpreads = maxReligionSpreads()
         if (abilityUsedCount["Religion Spread"] == null) return "" // That is, either the key doesn't exist, or it does exist and the value is null.

core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt

@@ -498,8 +498,8 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
                 return false
         }
         if (tile.naturalWonder != null) return false
-
-        if (!tile.canCivPassThrough(unit.civInfo)) return false
+        
+        if (!unit.canEnterForeignTerrain && !tile.canCivPassThrough(unit.civInfo)) return false
 
         val firstUnit = tile.getFirstUnit()
         if (firstUnit != null && firstUnit.civInfo != unit.civInfo && unit.civInfo.isAtWarWith(firstUnit.civInfo))

core/src/com/unciv/models/Religion.kt

@@ -12,7 +12,6 @@ class Religion() : INamed {
     override lateinit var name: String
     var iconName: String = "Pantheon"
     lateinit var foundingCivName: String
-    var holyCityId: String? = null
 
     var founderBeliefs: HashSet<String> = hashSetOf()
     var followerBeliefs: HashSet<String> = hashSetOf()
@@ -29,7 +28,6 @@ class Religion() : INamed {
     fun clone(): Religion {
         val toReturn = Religion(name, gameInfo, foundingCivName)
         toReturn.iconName = iconName
-        toReturn.holyCityId = holyCityId
         toReturn.founderBeliefs.addAll(founderBeliefs)
         toReturn.followerBeliefs.addAll(followerBeliefs)
         return toReturn

core/src/com/unciv/models/ruleset/unit/BaseUnit.kt

@@ -32,6 +32,7 @@ class BaseUnit : INamed, INonPerpetualConstruction, ICivilopediaText {
     var movement: Int = 0
     var strength: Int = 0
     var rangedStrength: Int = 0
+    var religiousStrength: Int = 0
     var range: Int = 2
     var interceptRange = 0
     lateinit var unitType: String
@@ -327,6 +328,8 @@ class BaseUnit : INamed, INonPerpetualConstruction, ICivilopediaText {
 
         if (unit.hasUnique("Religious Unit")) {
             unit.religion = cityConstructions.cityInfo.religion.getMajorityReligion()
+            if (unit.canSpreadReligion())
+                unit.abilityUsedCount["Religion Spread"] = 0
         }
 
         if (this.isCivilian()) return true // tiny optimization makes save files a few bytes smaller

core/src/com/unciv/ui/worldscreen/unit/UnitActions.kt

@@ -466,15 +466,12 @@ object UnitActions {
         val maxReligionSpreads = unit.maxReligionSpreads()
         if (!unit.abilityUsedCount.containsKey("Religion Spread")) return // This should be impossible anyways, but just in case
         if (maxReligionSpreads <= unit.abilityUsedCount["Religion Spread"]!!) return
-        val city = tile.getCity()
-        if (city == null) return
+        val city = tile.getCity() ?: return
         actionList += UnitAction(UnitActionType.SpreadReligion,
             title = "Spread [${unit.religion!!}]",
             action = {
                 unit.abilityUsedCount["Religion Spread"] = unit.abilityUsedCount["Religion Spread"]!! + 1
-                // ToDo: implement followers
-                city.religion.clearAllPressures()
-                city.religion.addPressure(unit.religion!!, 100)
+                city.religion.addPressure(unit.religion!!, unit.getPressureAddedFromSpread())
                 unit.currentMovement = 0f
                 if (unit.abilityUsedCount["Religion Spread"] == maxReligionSpreads) {
                     addGoldPerGreatPersonUsage(unit.civInfo)
@@ -487,7 +484,7 @@ object UnitActions {
     fun getImprovementConstructionActions(unit: MapUnit, tile: TileInfo): ArrayList<UnitAction> {
         val finalActions = ArrayList<UnitAction>()
         var uniquesToCheck = unit.getMatchingUniques("Can construct []")
-        if (unit.abilityUsedCount.containsKey("Religion Spread") && unit.abilityUsedCount["Religion Spread"]!! == 0 && unit.maxReligionSpreads() > 0)
+        if (unit.abilityUsedCount.containsKey("Religion Spread") && unit.abilityUsedCount["Religion Spread"]!! == 0 && unit.canSpreadReligion())
             uniquesToCheck += unit.getMatchingUniques("Can construct [] if it hasn't spread religion yet")
         for (unique in uniquesToCheck) {
             val improvementName = unique.params[0]

core/src/com/unciv/ui/worldscreen/unit/UnitTable.kt

@@ -163,10 +163,15 @@ class UnitTable(val worldScreen: WorldScreen) : Table(){
                     unitDescriptionTable.add(unit.promotions.XP.toString() + "/" + unit.promotions.xpForNextPromotion())
                 }
                 
-                if (unit.maxReligionSpreads() > 0) {
+                if (unit.canSpreadReligion()) {
                     unitDescriptionTable.add(ImageGetter.getStatIcon("Faith")).size(20f)
                     unitDescriptionTable.add(unit.getReligionString())
                 }
+                
+                if (unit.baseUnit.religiousStrength > 0) {
+                    unitDescriptionTable.add(ImageGetter.getStatIcon("ReligiousStrength")).size(20f)
+                    unitDescriptionTable.add((unit.baseUnit.religiousStrength - unit.religiousStrengthLost).toString())
+                }
 
                 if (unit.promotions.promotions.size != promotionsTable.children.size) // The unit has been promoted! Reload promotions!
                     selectedUnitHasChanged = true

docs/Credits.md

@@ -613,6 +613,7 @@ Unless otherwise specified, all the following are from [the Noun Project](https:
 * [Lock](https://thenounproject.com/search/?q=lock&i=3217613) by Vadim Solomakhin for locked tiles
 * [Hourglass](https://thenounproject.com/search/?q=hourglass&i=142268) by I Create Stuff for the 'Turn' icon
 * [Dove](https://thenounproject.com/search/?q=dove&i=1344084) by Sandra for Faith
+* [Shield](https://thenounproject.com/search/?q=shield&i=813568) by Gregor Cresnar for Religious Strength
 
 ## Main menu