From 3797817291d6bd4283a6f882d9a2bf97036a87cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9mi=20Dufour?= <remi.dufour@protonmail.com>
Date: Sun, 17 Dec 2023 21:03:31 +0100
Subject: [PATCH] Coast spread algorithm (#10741)

* new algo for coast placement

* optimization?

* change default max coast extension

* put spreadcoast in a function

* default change back, nextBoolean() and for loop
---
 .../logic/map/mapgenerator/MapGenerator.kt    | 34 ++++++++++++++-----
 1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/core/src/com/unciv/logic/map/mapgenerator/MapGenerator.kt b/core/src/com/unciv/logic/map/mapgenerator/MapGenerator.kt
index c6c6a32d50..710b93a1fd 100644
--- a/core/src/com/unciv/logic/map/mapgenerator/MapGenerator.kt
+++ b/core/src/com/unciv/logic/map/mapgenerator/MapGenerator.kt
@@ -238,6 +238,31 @@ class MapGenerator(val ruleset: Ruleset, private val coroutineScope: CoroutineSc
         }
     }
 
+    private fun spreadCoast(map: TileMap) {
+        for (i in 1..map.mapParameters.maxCoastExtension) {
+            val toCoast = mutableListOf<Tile>()
+            for (tile in map.values.filter { it.baseTerrain == Constants.ocean }) {
+                val tilesInDistance = tile.getTilesInDistance(1)
+                for (neighborTile in tilesInDistance) {
+                    if (neighborTile.isLand) {
+                        toCoast.add(tile)
+                        break
+                    } else if (neighborTile.baseTerrain == Constants.coast) {
+                        val randbool = randomness.RNG.nextBoolean()
+                        if (randbool) {
+                            toCoast.add(tile)
+                        }
+                        break
+                    }
+                }
+            }
+            for (tile in toCoast) {
+                tile.baseTerrain = Constants.coast
+                tile.setTransients()
+            }
+        }
+    }
+
     private fun spawnLakesAndCoasts(map: TileMap) {
 
         if (ruleset.terrains.containsKey(Constants.lakes)) {
@@ -277,14 +302,7 @@ class MapGenerator(val ruleset: Ruleset, private val coroutineScope: CoroutineSc
 
         //Coasts
         if (ruleset.terrains.containsKey(Constants.coast)) {
-            for (tile in map.values.filter { it.baseTerrain == Constants.ocean }) {
-                val coastLength =
-                    max(1, randomness.RNG.nextInt(max(1, map.mapParameters.maxCoastExtension)))
-                if (tile.getTilesInDistance(coastLength).any { it.isLand }) {
-                    tile.baseTerrain = Constants.coast
-                    tile.setTransients()
-                }
-            }
+            spreadCoast(map)
         }
     }