Remove tile improvements not in the current ruleset on normalizeTile

Mitigated mysterious crash in WorldMapHolder.updateTiles()

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

@@ -80,8 +80,8 @@ open class TileInfo {
         //Note to Future GGGuenni
         //TODO Use the following when terrainFeature got changed everywhere to support old saves in the future
         //if (terrainFeature != null){
-            //terrainFeatures.add(terrainFeature)
-            //terrainFeature = null
+        //terrainFeatures.add(terrainFeature)
+        //terrainFeature = null
         //}
     }
 
@@ -392,7 +392,7 @@ open class TileInfo {
                 || filter == "River" && isAdjacentToRiver()
                 || terrainFeatures.contains(filter)
                 || baseTerrainObject.uniques.contains(filter)
-                || getTerrainFeatures().any {it.uniques.contains(filter)}
+                || getTerrainFeatures().any { it.uniques.contains(filter) }
                 || improvement == filter
                 || civInfo != null && hasViewableResource(civInfo) && resource == filter
                 || filter == "Water" && isWater
@@ -643,11 +643,15 @@ open class TileInfo {
 
 
     private fun normalizeTileImprovement(ruleset: Ruleset) {
-        if (improvement!!.startsWith("StartingLocation")) {
+        if (improvement!!.startsWith("StartingLocation") == true) {
             if (!isLand || getLastTerrain().impassable) improvement = null
             return
         }
-        val improvementObject = ruleset.tileImprovements[improvement]!!
+        val improvementObject = ruleset.tileImprovements[improvement]
+        if (improvementObject == null) {
+            improvement = null
+            return
+        }
         improvement = null // Unset, and check if it can be reset. If so, do it, if not, invalid.
         if (canImprovementBeBuiltHere(improvementObject)
                 // Allow building 'other' improvements like city ruins, barb encampments, Great Improvements etc

core/src/com/unciv/logic/map/mapgenerator/MapLandmassGenerator.kt

@@ -13,11 +13,13 @@ import kotlin.math.pow
 class MapLandmassGenerator(val randomness: MapGenerationRandomness) {
 
     fun generateLand(tileMap: TileMap, ruleset: Ruleset) {
+        // This is to accommodate land-only mods
         if (ruleset.terrains.values.none { it.type == TerrainType.Water }) {
             for (tile in tileMap.values)
                 tile.baseTerrain = ruleset.terrains.keys.first()
             return
         }
+
         when (tileMap.mapParameters.type) {
             MapType.pangaea -> createPangea(tileMap)
             MapType.continents -> createTwoContinents(tileMap)
@@ -100,6 +102,8 @@ class MapLandmassGenerator(val randomness: MapGenerationRandomness) {
             longitudeFactor = min(longitudeFactor,
                 (tileMap.maxLongitude - abs(tileInfo.longitude)) / tileMap.maxLongitude) * 1.5f
 
+        // there's nothing magical about this, it's just what we got from playing around with a lot of different options -
+        //   the numbers can be changed if you find that something else creates better looking continents
         return min(0.2, -1.0 + (5.0 * longitudeFactor.pow(0.6f) + randomScale) / 3.0)
     }
 
@@ -130,7 +134,7 @@ class MapLandmassGenerator(val randomness: MapGenerationRandomness) {
     private fun generateLandCellularAutomata(tileMap: TileMap) {
         val numSmooth = 4
 
-        //init
+        // init
         for (tile in tileMap.values) {
             val terrainType = getInitialTerrainCellularAutomata(tile, tileMap.mapParameters)
             if (terrainType == TerrainType.Land) tile.baseTerrain = Constants.grassland
@@ -144,7 +148,6 @@ class MapLandmassGenerator(val randomness: MapGenerationRandomness) {
 
         for (loop in 0..numSmooth) {
             for (tileInfo in tileMap.values) {
-                //if (HexMath.getDistance(Vector2.Zero, tileInfo.position) < mapRadius) {
                 val numberOfLandNeighbors = tileInfo.neighbors.count { it.baseTerrain == grassland }
                 if (tileInfo.baseTerrain == grassland) { // land tile
                     if (numberOfLandNeighbors < 3)
@@ -153,9 +156,6 @@ class MapLandmassGenerator(val randomness: MapGenerationRandomness) {
                     if (numberOfLandNeighbors > 3)
                         tileInfo.baseTerrain = grassland
                 }
-                /*} else {
-                    tileInfo.baseTerrain = ocean
-                }*/
             }
         }
     }

core/src/com/unciv/ui/worldscreen/WorldMapHolder.kt

@@ -374,9 +374,11 @@ class WorldMapHolder(internal val worldScreen: WorldScreen, internal val tileMap
             }
         }
 
-        for (group in tileGroups[selectedTile]!!) {
-            group.showCircle(Color.WHITE)
-        }
+        // Same as below - randomly, tileGroups doesn't seem to contain the selected tile, and this doesn't seem duplicatable
+        val worldTileGroupsForSelectedTile = tileGroups[selectedTile]
+        if (worldTileGroupsForSelectedTile != null)
+            for (group in worldTileGroupsForSelectedTile)
+                group.showCircle(Color.WHITE)
 
         zoom(scaleX) // zoom to current scale, to set the size of the city buttons after "next turn"
     }