Added Stealth tech and Stealth Bombers (#4271)

* Changed some interception-related uniques

- "Can not be intercepted" -> "Cannot be intercepted"
  This really irked me, and the new version is also how it is written
  in the wiki.
- "Reduces damage taken from interception by 50%" ->
  "Damage taken from interception reduced by [50]%"

* Added "Cannot be carried by [unitFilter] units" unique

* Added an icon for Stealth

* Added Stealth technology and the Stealth Bomber

* Possibly fixed incorrect rounding for interception damage bonus

* Various code style changes

* Made Stealth Bomber interceptable, but with 100% damage reduction

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

@@ -621,8 +621,14 @@
 			{
 				"name": "Nanotechnology",
 				"row": 7,
-				"prerequisites": ["Robotics","Lasers"],
+				"prerequisites": ["Robotics"],
 				"quote": "'The impact of nanotechnology is expected to exceed the impact that the electronics revolution has had on our lives.' - Richard Schwartz"
+			},
+			{
+				"name": "Stealth",
+				"row": 8,
+				"prerequisites": ["Robotics", "Lasers"],
+				"quote": "'Be extremely subtle, even to the point of formlessness, be extremely mysterious, even to the point of soundlessness. Thereby you can be the director of the opponent' state.' – Sun Tzu"
 			}
 		]
 	},
@@ -636,7 +642,7 @@
 			{
 				"name": "Future Tech",
 				"row": 5,
-				"prerequisites": ["Particle Physics", "Nuclear Fusion", "Nanotechnology"],
+				"prerequisites": ["Particle Physics", "Nuclear Fusion", "Nanotechnology", "Stealth"],
 				"uniques": ["Who knows what the future holds?", "Can be continually researched"],
 				"quote": "'I think we agree, the past is over.' - George W. Bush"
 			}

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

@@ -287,7 +287,7 @@
 	{
 		"name": "Evasion",
 		"prerequisites": ["Siege II", "Bombardment II"],
-		"effect": "Reduces damage taken from interception by 50%",
+		"effect": "Damage taken from interception reduced by [50]%",
 		"unitTypes": ["Bomber"]
 	},
 	

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

@@ -1134,7 +1134,7 @@
 		"cost": 375,
 		"requiredTech": "Radar",
 		"requiredResource": "Oil",
-		//"upgradesTo": "Stealth Bomber",
+		"upgradesTo": "Stealth Bomber",
 		"attackSound": "shot"
 	},
 	{
@@ -1150,7 +1150,7 @@
 		"requiredTech": "Radar",
 		"requiredResource": "Oil",
 		"promotions": ["Evasion", "Siege I"],
-		//"upgradesTo": "Stealth Bomber",
+		"upgradesTo": "Stealth Bomber",
 		"attackSound": "shot"
 	},
 	{
@@ -1350,22 +1350,19 @@
 		"requiredResource": "Uranium",
 		"uniques": ["Can move after attacking", "No defensive terrain bonus"]
 	},
-	/*
 	{
 		"name": "Stealth Bomber",
 		"unitType": "Bomber",
 		"movement": 2,
 		"strength": 85,
-		"rangedStrength": 65,
+		"rangedStrength": 85,
 		"range": 20,
 		"cost": 425,
 		"requiredTech": "Stealth",
 		"requiredResource": "Aluminum",
-		"uniques": ["Evasion", "6 tiles in every direction always visible"],
+		"uniques": ["Damage taken from interception reduced by [100]%", "Cannot be carried by [Carrier] units", "6 tiles in every direction always visible"],
 		"attackSound": "shot"
-		// cannot be based on carrier
 	},
-	*/
 
 	/* Great people */
 

core/src/com/unciv/logic/battle/Battle.kt

@@ -579,13 +579,19 @@ object Battle {
 
     private fun tryInterceptAirAttack(attacker: MapUnitCombatant, defender: ICombatant) {
         if (attacker.unit.hasUnique("Cannot be intercepted")) return
+        // Deprecated since 3.15.6
+            if (attacker.unit.hasUnique("Can not be intercepted")) return
+        // End deprecation
         val attackedTile = defender.getTile()
         for (interceptor in defender.getCivInfo().getCivUnits().filter { it.canIntercept(attackedTile) }) {
             if (Random().nextFloat() > 100f / interceptor.interceptChance()) continue
 
             var damage = BattleDamage.calculateDamageToDefender(MapUnitCombatant(interceptor), null, attacker)
-            damage += damage * interceptor.interceptDamagePercentBonus() / 100
-            if (attacker.unit.hasUnique("Reduces damage taken from interception by 50%")) damage /= 2
+
+            var damageFactor = 1f + interceptor.interceptDamagePercentBonus().toFloat() / 100f
+            damageFactor *= attacker.unit.receivedInterceptDamageFactor()
+
+            damage = (damage.toFloat() * damageFactor).toInt()
 
             attacker.takeDamage(damage)
             interceptor.attacksThisTurn++

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

@@ -14,6 +14,7 @@ import com.unciv.models.ruleset.tile.TileImprovement
 import com.unciv.models.ruleset.unit.BaseUnit
 import com.unciv.models.ruleset.unit.UnitType
 import java.text.DecimalFormat
+import kotlin.math.pow
 import kotlin.random.Random
 
 /**
@@ -835,6 +836,7 @@ class MapUnit {
     fun canTransport(unit: MapUnit): Boolean {
         if (owner != unit.owner) return false
         if (!isTransportTypeOf(unit)) return false
+        if (unit.getMatchingUniques("Cannot be carried by [] units").any{matchesFilter(it.params[0])}) return false
         if (currentTile.airUnits.count { it.isTransported } >= carryCapacity(unit)) return false
         return true
     }
@@ -844,6 +846,16 @@ class MapUnit {
             .sumBy { it.params[0].toInt() }
     }
 
+    fun receivedInterceptDamageFactor(): Float {
+        var damageFactor = 1f
+        for (unique in getMatchingUniques("Damage taken from interception reduced by []%"))
+            damageFactor *= 1f - unique.params[0].toFloat() / 100f
+        // Deprecated since 3.15.6
+            damageFactor *= 0.5f.pow(getUniques().count{it.text == "Reduces damage taken from interception by 50%"})
+        // End deprecation
+        return damageFactor
+    }
+
     private fun getTerrainDamage() {
         // hard coded mountain damage for now
         if (getTile().baseTerrain == Constants.mountain) {

docs/Credits.md

@@ -472,6 +472,7 @@ Unless otherwise specified, all the following are from [the Noun Project](https:
 * [Atom](https://thenounproject.com/term/atom/1586852/) By Kelsey Armstrong for Particle Physics
 * [Thermonuclear fusion](https://thenounproject.com/search/?q=fusion&i=3292735) by Olena Panasovska, UA for Nuclear Fusion
 * [telecommunications](https://thenounproject.com/search/?q=telecommunications&i=3191260) by Wichai Wi for Telcommunications
+* [Radar](https://thenounproject.com/term/radar/1546196/) By CINDYFLA, ID for Stealth
 * [Information Technology](https://thenounproject.com/term/information-technology/1927668/) By Vectors Markeet for Future Tech
 
 ## Terrain