Implemented line-of-sight according to terrain

android/build.gradle

@@ -21,8 +21,8 @@ android {
         applicationId "com.unciv.game"
         minSdkVersion 9
         targetSdkVersion 25
-        versionCode 18
-        versionName "1.0"
+        versionCode 19
+        versionName "1.1.0"
     }
     buildTypes {
         release {

core/src/com/unciv/civinfo/CivilizationTech.java

@@ -76,7 +76,7 @@ public class CivilizationTech{
                             }
                         }
                     }
-            
+
         }
     }
 

core/src/com/unciv/civinfo/MapUnit.java

@@ -56,7 +56,7 @@ public class MapUnit{
         return tile.improvement==null
                 && tile.canBuildImprovement(GameBasics.TileImprovements.get(chooseImprovement(tile)))
                 && tile.hasViewableResource()
-                && CivilizationInfo.current().tileMap.getTilesAtDistance(tile.position,1).any(new Predicate<TileInfo>() {
+                && tile.getNeighbors().any(new Predicate<TileInfo>() {
             @Override
             public boolean evaluate(TileInfo arg0) {
                 return arg0.owner!=null;

core/src/com/unciv/civinfo/TileInfo.java

@@ -167,4 +167,8 @@ public class TileInfo
         otherTile.unit = unit;
         unit = null;
     }
+
+    public LinqCollection<TileInfo> getNeighbors(){
+        return CivilizationInfo.current().tileMap.getTilesAtDistance(position,1);
+    }
 }

core/src/com/unciv/civinfo/TileMap.java

@@ -124,17 +124,6 @@ public class TileMap{
         return distanceToTiles;
     }
 
-    public class BfsInfo{
-
-        final TileInfo parent;
-        final int totalDistance;
-
-        public BfsInfo(TileInfo parent, int totalDistance) {
-            this.parent = parent;
-            this.totalDistance = totalDistance;
-        }
-    }
-
     public LinqCollection<TileInfo> getShortestPath(Vector2 origin, Vector2 destination, float currentMovement, int maxMovement){
         LinqCollection<TileInfo> toCheck = new LinqCollection<TileInfo>(get(origin));
         LinqHashMap<TileInfo,TileInfo> parents = new LinqHashMap<TileInfo, TileInfo>();
@@ -183,5 +172,33 @@ public class TileMap{
         }).unit = GameBasics.Units.get(unit).getMapUnit(); // And if there's none, then kill me.
     }
 
+    public int getTileHeight(TileInfo tileInfo){
+        int height=0;
+        if(new LinqCollection<String>("Forest","Jungle").contains(tileInfo.terrainFeature)) height+=1;
+        if("Hill".equals(tileInfo.baseTerrain)) height+=2;
+        return height;
+    }
+
+    public LinqCollection<TileInfo> getViewableTiles(Vector2 position, int sightDistance){
+        final LinqCollection<TileInfo> tiles = getTilesInDistance(position,1);
+        if(get(position).baseTerrain.equals("Hill")) sightDistance+=1;
+        for (int i = 0; i <= sightDistance; i++) {
+            LinqCollection<TileInfo> tilesForLayer = new LinqCollection<TileInfo>();
+            for (final TileInfo tile : getTilesAtDistance(position, i))
+                if (tile.getNeighbors().any(new Predicate<TileInfo>() {
+                    @Override
+                    public boolean evaluate(TileInfo arg0) {
+                        if (!tiles.contains(arg0))
+                            return false; // Basically, if there's a viewable neighbor which is either flatlands, or I'm taller than him
+                        int tileHeight = getTileHeight(arg0);
+                        return tileHeight == 0 || getTileHeight(tile) > tileHeight;
+                    }
+                })) tilesForLayer.add(tile);
+            tiles.addAll(tilesForLayer);
+        }
+
+        return tiles;
+    }
+
 }
 

core/src/com/unciv/game/TileGroup.java

@@ -107,7 +107,7 @@ public class TileGroup extends Group {
         }
 
         if(tileInfo.roadStatus != RoadStatus.None){
-            for (TileInfo neighbor : CivilizationInfo.current().tileMap.getTilesAtDistance(tileInfo.position,1)) {
+            for (TileInfo neighbor : tileInfo.getNeighbors()) {
                 if (neighbor.roadStatus == RoadStatus.None) continue;
                 if (!roadImages.containsKey(neighbor.position.toString())) {
                     Image image = ImageGetter.getImage(ImageGetter.WhiteDot);

core/src/com/unciv/game/WorldScreen.java

@@ -701,8 +701,8 @@ public class WorldScreen extends CameraStageBaseScreen {
                         return arg0.unit != null;
                     }
                 }))
-            for (Vector2 vector : HexMath.GetVectorsInDistance(tile.position, 2))
-                ViewableVectorStrings.add(vector.toString());
+            for (TileInfo tileInfo : game.civInfo.tileMap.getViewableTiles(tile.position,2))
+                ViewableVectorStrings.add(tileInfo.position.toString());
 
         for (String string : ViewableVectorStrings)
             if (tileGroups.containsKey(string))