The ImageGetter changes rulesets correctly when entering\exiting scenario editor

core/src/com/unciv/MainMenuScreen.kt

@@ -50,6 +50,7 @@ class MainMenuScreen: CameraStageBaseScreen() {
             val newMap = MapGenerator(RulesetCache.getBaseRuleset())
                     .generateMap(MapParameters().apply { size = MapSize.Small; type = MapType.default })
             Gdx.app.postRunnable { // for GL context
+                ImageGetter.setNewRuleset(RulesetCache.getBaseRuleset())
                 val mapHolder = EditorMapHolder(MapEditorScreen(), newMap)
                 backgroundTable.addAction(Actions.sequence(
                         Actions.fadeOut(0f),

core/src/com/unciv/logic/civilization/diplomacy/DiplomacyManager.kt

@@ -232,7 +232,7 @@ class DiplomacyManager() {
      *  This includes friendly and allied city-states and the open border treaties.
      */
     fun isConsideredFriendlyTerritory(): Boolean {
-        if(civInfo.isCityState() && relationshipLevel() >= RelationshipLevel.Friend)
+        if (civInfo.isCityState() && relationshipLevel() >= RelationshipLevel.Friend)
             return true
         return hasOpenBorders
     }

core/src/com/unciv/ui/mapeditor/GameParametersScreen.kt

@@ -40,9 +40,11 @@ class GameParametersScreen(var mapEditorScreen: MapEditorScreen): IPreviousScree
             mapEditorScreen.ruleset.add(ruleset)
             mapEditorScreen.tileEditorOptions.update()
             // Remove resources that are not applicable to this scenario
-            for(tile in mapEditorScreen.tileMap.values){
-                if(tile.resource!=null && !ruleset.tileResources.containsKey(tile.resource!!))
-                    tile.resource=null
+            for(tile in mapEditorScreen.tileMap.values) {
+                if (tile.resource != null && !ruleset.tileResources.containsKey(tile.resource!!))
+                    tile.resource = null
+                if (tile.improvement != null && !ruleset.tileImprovements.containsKey(tile.improvement!!))
+                    tile.improvement = null
             }
 
             mapEditorScreen.mapHolder.updateTileGroups()

core/src/com/unciv/ui/mapeditor/MapEditorScreen.kt

@@ -12,6 +12,7 @@ import com.unciv.logic.MapSaver
 import com.unciv.logic.map.Scenario
 import com.unciv.logic.map.TileInfo
 import com.unciv.logic.map.TileMap
+import com.unciv.models.ruleset.Ruleset
 import com.unciv.models.ruleset.RulesetCache
 import com.unciv.models.translations.tr
 import com.unciv.ui.newgamescreen.GameSetupInfo
@@ -23,7 +24,7 @@ class MapEditorScreen(): CameraStageBaseScreen() {
     var tileMap = TileMap()
     var scenarioName = ""   // when loading map: mapName is taken as default for scenarioName
     var scenario: Scenario? = null // main indicator whether scenario information is present
-    var ruleset = RulesetCache.getBaseRuleset()
+    var ruleset = Ruleset().apply { add(RulesetCache.getBaseRuleset()) } // Since we change this in scenarios, we can't take the base ruleset directly
 
     var gameSetupInfo = GameSetupInfo()
     lateinit var mapHolder: EditorMapHolder
@@ -64,12 +65,11 @@ class MapEditorScreen(): CameraStageBaseScreen() {
         gameSetupInfo.gameParameters = scenario.gameParameters
 
         ruleset = RulesetCache.getComplexRuleset(scenario.gameParameters)
-        ImageGetter.ruleset = ruleset
-        ImageGetter.setTextureRegionDrawables()
         initialize()
     }
 
     fun initialize() {
+        ImageGetter.setNewRuleset(ruleset)
         tileMap.setTransients(ruleset,false)
 
         mapHolder = EditorMapHolder(this, tileMap)

core/src/com/unciv/ui/utils/ImageGetter.kt

@@ -37,6 +37,12 @@ object ImageGetter {
         setTextureRegionDrawables()
     }
 
+    fun setNewRuleset(ruleset: Ruleset) {
+        if (this.ruleset == ruleset) return
+        this.ruleset = ruleset
+        setTextureRegionDrawables()
+    }
+
 
     fun setTextureRegionDrawables(){
         textureRegionDrawables.clear()
@@ -134,7 +140,9 @@ object ImageGetter {
 
         val iconGroup = getImage("ImprovementIcons/$improvementName").surroundWithCircle(size)
 
-        val improvement = ruleset.tileImprovements[improvementName]!!
+        val improvement = ruleset.tileImprovements[improvementName]
+        if(improvement==null)
+            throw Exception("No improvement $improvementName found in ruleset!")
         when {
             improvement.food>0 -> iconGroup.circle.color= foodCircleColor
             improvement.production>0 -> iconGroup.circle.color= productionCircleColor