refactors mapgen into chained builders

src/map_builders/wfc/mod.rs

@@ -1,154 +1,76 @@
-use super::{
-    generate_voronoi_spawn_regions, remove_unreachable_areas_returning_most_distant, spawner, Map, MapBuilder,
-    Position, TileType, SHOW_MAPGEN,
-};
-
-mod common;
-use common::MapChunk;
-mod constraints;
-mod solver;
+use super::{BuilderMap, Map, MetaMapBuilder, TileType};
 use rltk::RandomNumberGenerator;
-use solver::Solver;
-use std::collections::HashMap;
+mod common;
+use common::*;
+mod constraints;
+use constraints::*;
+mod solver;
+use solver::*;
 
-pub struct WaveFunctionCollapseBuilder {
-    map: Map,
-    starting_position: Position,
-    depth: i32,
-    history: Vec<Map>,
-    noise_areas: HashMap<i32, Vec<usize>>,
-    derive_from: Option<Box<dyn MapBuilder>>,
-    spawn_list: Vec<(usize, String)>,
-}
+/// Provides a map builder using the Wave Function Collapse algorithm.
+pub struct WaveFunctionCollapseBuilder {}
 
-impl MapBuilder for WaveFunctionCollapseBuilder {
-    fn build_map(&mut self, rng: &mut RandomNumberGenerator) {
-        return self.build(rng);
-    }
-    //  Getters
-    fn get_map(&mut self) -> Map {
-        return self.map.clone();
-    }
-    fn get_starting_pos(&mut self) -> Position {
-        return self.starting_position.clone();
-    }
-    fn get_spawn_list(&self) -> &Vec<(usize, String)> {
-        return &self.spawn_list;
-    }
-    // Mapgen visualisation stuff
-    fn get_snapshot_history(&self) -> Vec<Map> {
-        return self.history.clone();
-    }
-    fn take_snapshot(&mut self) {
-        if SHOW_MAPGEN {
-            let mut snapshot = self.map.clone();
-            for v in snapshot.revealed_tiles.iter_mut() {
-                *v = true;
-            }
-            self.history.push(snapshot);
-        }
+impl MetaMapBuilder for WaveFunctionCollapseBuilder {
+    fn build_map(&mut self, rng: &mut rltk::RandomNumberGenerator, build_data: &mut BuilderMap) {
+        self.build(rng, build_data);
     }
 }
 
-#[allow(dead_code)]
 impl WaveFunctionCollapseBuilder {
-    pub fn new(new_depth: i32, derive_from: Option<Box<dyn MapBuilder>>) -> WaveFunctionCollapseBuilder {
-        WaveFunctionCollapseBuilder {
-            map: Map::new(new_depth),
-            starting_position: Position { x: 0, y: 0 },
-            depth: new_depth,
-            history: Vec::new(),
-            noise_areas: HashMap::new(),
-            derive_from,
-            spawn_list: Vec::new(),
-        }
+    /// Constructor for wfc.
+    #[allow(dead_code)]
+    pub fn new() -> Box<WaveFunctionCollapseBuilder> {
+        Box::new(WaveFunctionCollapseBuilder {})
     }
 
-    pub fn derived_map(new_depth: i32, builder: Box<dyn MapBuilder>) -> WaveFunctionCollapseBuilder {
-        WaveFunctionCollapseBuilder::new(new_depth, Some(builder))
-    }
-
-    fn build(&mut self, rng: &mut RandomNumberGenerator) {
+    fn build(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
         const CHUNK_SIZE: i32 = 8;
+        build_data.take_snapshot();
 
-        let prebuilder = &mut self.derive_from.as_mut().unwrap();
-        prebuilder.build_map(rng);
-        self.map = prebuilder.get_map();
-        self.history = prebuilder.get_snapshot_history();
-        for t in self.map.tiles.iter_mut() {
-            if *t == TileType::DownStair {
-                *t = TileType::Floor;
-            }
-        }
-        self.take_snapshot();
+        let patterns = build_patterns(&build_data.map, CHUNK_SIZE, true, true);
+        let constraints = patterns_to_constraints(patterns, CHUNK_SIZE);
+        self.render_tile_gallery(&constraints, CHUNK_SIZE, build_data);
 
-        let patterns = constraints::build_patterns(&self.map, CHUNK_SIZE, true, true);
-        let constraints = common::patterns_to_constraints(patterns, CHUNK_SIZE);
-        self.render_tile_gallery(&constraints, CHUNK_SIZE);
-
-        // Call solver
-        self.map = Map::new(self.depth);
+        build_data.map = Map::new(build_data.map.depth);
         loop {
-            let mut solver = Solver::new(constraints.clone(), CHUNK_SIZE, &self.map);
-            while !solver.iteration(&mut self.map, rng) {
-                self.take_snapshot();
+            let mut solver = Solver::new(constraints.clone(), CHUNK_SIZE, &build_data.map);
+            while !solver.iteration(&mut build_data.map, rng) {
+                build_data.take_snapshot();
             }
-            self.take_snapshot();
+            build_data.take_snapshot();
             if solver.possible {
                 break;
-            }
-        }
-
-        // Find a starting point; start at the middle and walk left until we find an open tile
-        self.starting_position = Position { x: self.map.width / 2, y: self.map.height / 2 };
-        let mut start_idx = self.map.xy_idx(self.starting_position.x, self.starting_position.y);
-        while self.map.tiles[start_idx] != TileType::Floor {
-            self.starting_position.x -= 1;
-            start_idx = self.map.xy_idx(self.starting_position.x, self.starting_position.y);
-        }
-        self.take_snapshot();
-
-        // Find all tiles we can reach from the starting point
-        let exit_tile = remove_unreachable_areas_returning_most_distant(&mut self.map, start_idx);
-        self.take_snapshot();
-
-        // Place the stairs
-        self.map.tiles[exit_tile] = TileType::DownStair;
-        self.take_snapshot();
-
-        // Now we build a noise map for use in spawning entities later
-        self.noise_areas = generate_voronoi_spawn_regions(&self.map, rng);
-
-        // Spawn the entities
-        for area in self.noise_areas.iter() {
-            spawner::spawn_region(&self.map, rng, area.1, self.depth, &mut self.spawn_list);
+            } // If it has hit an impossible condition, try again
         }
+        build_data.spawn_list.clear();
     }
 
-    fn render_tile_gallery(&mut self, constraints: &Vec<MapChunk>, chunk_size: i32) {
-        self.map = Map::new(0);
+    fn render_tile_gallery(&mut self, constraints: &[MapChunk], chunk_size: i32, build_data: &mut BuilderMap) {
+        build_data.map = Map::new(0);
         let mut counter = 0;
         let mut x = 1;
         let mut y = 1;
         while counter < constraints.len() {
-            constraints::render_pattern_to_map(&mut self.map, &constraints[counter], chunk_size, x, y);
+            render_pattern_to_map(&mut build_data.map, &constraints[counter], chunk_size, x, y);
+
             x += chunk_size + 1;
-            if x + chunk_size > self.map.width {
-                // Next row
+            if x + chunk_size > build_data.map.width {
+                // Move to the next row
                 x = 1;
                 y += chunk_size + 1;
-                self.take_snapshot();
 
-                if y + chunk_size > self.map.height {
-                    // Next page
-                    self.take_snapshot();
-                    self.map = Map::new(0);
+                if y + chunk_size > build_data.map.height {
+                    // Move to the next page
+                    build_data.take_snapshot();
+                    build_data.map = Map::new(0);
+
                     x = 1;
                     y = 1;
                 }
             }
+
             counter += 1;
         }
-        self.take_snapshot();
+        build_data.take_snapshot();
     }
 }