Resolved #12477 - Limited, but performant, edge filters

This brings back 'edges below improvements'

core/src/com/unciv/ui/components/tilegroups/layers/TileLayerTerrain.kt

@@ -78,14 +78,19 @@ class TileLayerTerrain(tileGroup: TileGroup, size: Float) : TileLayer(tileGroup,
         val terrainImages = if (tile.naturalWonder != null)
             sequenceOf(tile.baseTerrain, tile.naturalWonder!!)
         else  sequenceOf(tile.baseTerrain) + tile.terrainFeatures.asSequence()
+        val edgeImages = getEdgeTileLocations()
         val allTogether = (terrainImages + resourceAndImprovementSequence).joinToString("+")
         val allTogetherLocation = strings().getTile(allTogether)
 
+        // If the tilesetconfig *explicitly* lists the terrains+improvements etc, we can't know where in that list to place the edges
+        //   So we default to placing them over everything else.
+        // If there is no explicit list, then we can know to place them between the terrain and the improvement
         return when {
-            strings().tileSetConfig.ruleVariants[allTogether] != null -> baseHexagon + strings().tileSetConfig.ruleVariants[allTogether]!!.map { strings().getTile(it) }
-            ImageGetter.imageExists(allTogetherLocation) -> baseHexagon + allTogetherLocation
-            tile.naturalWonder != null -> getNaturalWonderBackupImage(baseHexagon)
-            else -> baseHexagon + getTerrainImageLocations(terrainImages) + getImprovementAndResourceImages(resourceAndImprovementSequence)
+            strings().tileSetConfig.ruleVariants[allTogether] != null -> baseHexagon + 
+                    strings().tileSetConfig.ruleVariants[allTogether]!!.map { strings().getTile(it) } + edgeImages
+            ImageGetter.imageExists(allTogetherLocation) -> baseHexagon + allTogetherLocation + edgeImages
+            tile.naturalWonder != null -> getNaturalWonderBackupImage(baseHexagon) + edgeImages
+            else -> baseHexagon + getTerrainImageLocations(terrainImages) + edgeImages + getImprovementAndResourceImages(resourceAndImprovementSequence)
         }
     }
 
@@ -102,10 +107,17 @@ class TileLayerTerrain(tileGroup: TileGroup, size: Float) : TileLayer(tileGroup,
         val direction = NeighborDirection.fromVector(vectorToNeighbor)
             ?: return emptyList()
         val possibleEdgeFiles = strings().edgeImagesByPosition[direction] ?: return emptyList()
+
+        // Required for performance - full matchesFilter is too expensive for something that needs to run every update()
+        fun matchesFilterMinimal(originTile: Tile, filter: String): Boolean {
+            if (originTile.allTerrains.any { it.name == filter }) return true
+            if (originTile.getBaseTerrain().type.name == filter) return true
+            return false
+        }
 
         return possibleEdgeFiles.filter {
-            if (!originTile.matchesFilter(it.originTileFilter)) return@filter false
-            if (!neighborTile.matchesFilter(it.destinationTileFilter)) return@filter false
+            if (!matchesFilterMinimal(originTile, it.originTileFilter)) return@filter false
+            if (!matchesFilterMinimal(neighborTile, it.destinationTileFilter)) return@filter false
             return@filter true
         }.map { it.fileName }
     }
@@ -119,11 +131,9 @@ class TileLayerTerrain(tileGroup: TileGroup, size: Float) : TileLayer(tileGroup,
         }
         tileImageIdentifiers = tileBaseImageLocations
 
-        val allImages = tileBaseImageLocations + getEdgeTileLocations()
-
         for (image in tileBaseImages) image.remove()
         tileBaseImages.clear()
-        for (baseLocation in allImages) {
+        for (baseLocation in tileBaseImageLocations) {
             // Here we check what actual tiles exist, and pick one - not at random, but based on the tile location,
             // so it stays consistent throughout the game
             if (!ImageGetter.imageExists(baseLocation)) continue

docs/Modders/Creating-a-custom-tileset.md

@@ -162,6 +162,11 @@ The name of the tile should be `<tile name>-<origin tile filter>-<destination ti
 - TopLeft
 - TopRight
 
+And where the tile filter is one of:
+- Terrain name
+- Feature name
+- Terrain type (Land/Water)
+
 For example: `Cliff-Hills-Coast-Top.png`
 
 The initial name has no bearing on the image used, it is just a way to group images together.