From ee9e96e828cbc4f14de1c78bc5c1d49cfd4cd6bc Mon Sep 17 00:00:00 2001
From: Timothy Warren <twarren@nabancard.com>
Date: Wed, 15 Dec 2021 13:50:27 -0500
Subject: [PATCH] Implment MetaMapBuilder for Cellular Automata map builder

---
 src/map_builders/cellular_automata.rs | 109 ++++++++++++++------------
 1 file changed, 58 insertions(+), 51 deletions(-)

diff --git a/src/map_builders/cellular_automata.rs b/src/map_builders/cellular_automata.rs
index 0e055cf..af3b9bb 100644
--- a/src/map_builders/cellular_automata.rs
+++ b/src/map_builders/cellular_automata.rs
@@ -1,6 +1,6 @@
 use rltk::RandomNumberGenerator;
 
-use crate::map_builders::{BuilderMap, InitialMapBuilder};
+use crate::map_builders::{BuilderMap, InitialMapBuilder, MetaMapBuilder};
 use crate::TileType;
 
 pub struct CellularAutomataBuilder {}
@@ -12,11 +12,67 @@ impl InitialMapBuilder for CellularAutomataBuilder {
     }
 }
 
+impl MetaMapBuilder for CellularAutomataBuilder {
+    #[allow(dead_code)]
+    fn build_map(&mut self, _rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
+        self.apply_iteration(build_data);
+    }
+}
+
 impl CellularAutomataBuilder {
     pub fn new() -> Box<CellularAutomataBuilder> {
         Box::new(CellularAutomataBuilder {})
     }
 
+    fn apply_iteration(&mut self, build_data: &mut BuilderMap) {
+        let mut newtiles = build_data.map.tiles.clone();
+
+        for y in 1..build_data.map.height - 1 {
+            for x in 1..build_data.map.width - 1 {
+                let idx = build_data.map.xy_idx(x, y);
+                let mut neighbors = 0;
+
+                if build_data.map.tiles[idx - 1] == TileType::Wall {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx + 1] == TileType::Wall {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx - build_data.map.width as usize] == TileType::Wall {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx + build_data.map.width as usize] == TileType::Wall {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx - (build_data.map.width as usize - 1)] == TileType::Wall
+                {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx - (build_data.map.width as usize + 1)] == TileType::Wall
+                {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx + (build_data.map.width as usize - 1)] == TileType::Wall
+                {
+                    neighbors += 1;
+                }
+                if build_data.map.tiles[idx + (build_data.map.width as usize + 1)] == TileType::Wall
+                {
+                    neighbors += 1;
+                }
+
+                if neighbors > 4 || neighbors == 0 {
+                    newtiles[idx] = TileType::Wall;
+                } else {
+                    newtiles[idx] = TileType::Floor;
+                }
+            }
+        }
+
+        build_data.map.tiles = newtiles.clone();
+        build_data.take_snapshot();
+    }
+
     fn build(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
         // First we completely randomize the map, setting 55% of it to be floor.
         for y in 1..build_data.map.height - 1 {
@@ -36,56 +92,7 @@ impl CellularAutomataBuilder {
 
         // Now we iteratively apply cellular automata rules
         for _i in 0..15 {
-            let mut newtiles = build_data.map.tiles.clone();
-
-            for y in 1..build_data.map.height - 1 {
-                for x in 1..build_data.map.width - 1 {
-                    let idx = build_data.map.xy_idx(x, y);
-                    let mut neighbors = 0;
-
-                    if build_data.map.tiles[idx - 1] == TileType::Wall {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx + 1] == TileType::Wall {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx - build_data.map.width as usize] == TileType::Wall {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx + build_data.map.width as usize] == TileType::Wall {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx - (build_data.map.width as usize - 1)]
-                        == TileType::Wall
-                    {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx - (build_data.map.width as usize + 1)]
-                        == TileType::Wall
-                    {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx + (build_data.map.width as usize - 1)]
-                        == TileType::Wall
-                    {
-                        neighbors += 1;
-                    }
-                    if build_data.map.tiles[idx + (build_data.map.width as usize + 1)]
-                        == TileType::Wall
-                    {
-                        neighbors += 1;
-                    }
-
-                    if neighbors > 4 || neighbors == 0 {
-                        newtiles[idx] = TileType::Wall;
-                    } else {
-                        newtiles[idx] = TileType::Floor;
-                    }
-                }
-            }
-
-            build_data.map.tiles = newtiles.clone();
-            build_data.take_snapshot();
+            self.apply_iteration(build_data);
         }
     }
 }