Refactor waveform_collapse map builder to use Rust builder pattern

src/map_builders.rs

@@ -168,7 +168,8 @@ pub trait MapBuilder {
 pub fn random_builder(new_depth: i32, rng: &mut RandomNumberGenerator) -> BuilderChain {
     let mut builder = BuilderChain::new(new_depth);
     builder
-        .start_with(CellularAutomataBuilder::new())
+        .start_with(VoronoiCellBuilder::pythagoras())
+        .with(WaveformCollapseBuilder::new())
         .with(AreaStartingPosition::new(XStart::Center, YStart::Center))
         .with(CullUnreachable::new())
         .with(VoronoiSpawning::new())

src/map_builders/waveform_collapse.rs

@@ -13,167 +13,71 @@ use super::common::{
     generate_voronoi_spawn_regions, remove_unreachable_areas_returning_most_distant,
 };
 use super::MapBuilder;
+use crate::map_builders::{BuilderMap, MetaMapBuilder};
 use crate::{spawner, Map, Position, TileType, SHOW_MAPGEN_VISUALIZER};
 
-pub struct WaveformCollapseBuilder {
+pub struct WaveformCollapseBuilder {}
-    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)>,
-}
 
-impl MapBuilder for WaveformCollapseBuilder {
+impl MetaMapBuilder for WaveformCollapseBuilder {
-    fn get_map(&self) -> Map {
+    fn build_map(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
-        self.map.clone()
+        self.build(rng, build_data);
-    }
-
-    fn get_starting_position(&self) -> Position {
-        self.starting_position
-    }
-
-    fn get_snapshot_history(&self) -> Vec<Map> {
-        self.history.clone()
-    }
-
-    fn build_map(&mut self) {
-        self.build();
-    }
-
-    fn take_snapshot(&mut self) {
-        if SHOW_MAPGEN_VISUALIZER {
-            let mut snapshot = self.map.clone();
-            for v in snapshot.revealed_tiles.iter_mut() {
-                *v = true;
-            }
-            self.history.push(snapshot);
-        }
-    }
-
-    fn get_spawn_list(&self) -> &Vec<(usize, String)> {
-        &self.spawn_list
     }
 }
 
 impl WaveformCollapseBuilder {
-    /// Generic constructor for waveform collapse.
+    /// Constructor for waveform collapse.
-    /// # Arguments
+    #[allow(dead_code)]
-    /// * new_depth - the new map depth
+    pub fn new() -> Box<WaveformCollapseBuilder> {
-    /// * derive_from - either None, or a boxed MapBuilder, as output by `random_builder`
+        Box::new(WaveformCollapseBuilder {})
-    pub fn new(
-        new_depth: i32,
-        derive_from: Option<Box<dyn MapBuilder>>,
-    ) -> WaveformCollapseBuilder {
-        WaveformCollapseBuilder {
-            map: Map::new(new_depth),
-            starting_position: Position::default(),
-            depth: new_depth,
-            history: Vec::new(),
-            noise_areas: HashMap::new(),
-            derive_from,
-            spawn_list: Vec::new(),
-        }
     }
 
-    /// Derives a map from a pre-existing map builder.
+    fn build(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
-    /// # Arguments
-    /// * new_depth - the new map depth
-    /// * derive_from - either None, or a boxed MapBuilder, as output by `random_builder`
-    pub fn derived_map(new_depth: i32, builder: Box<dyn MapBuilder>) -> WaveformCollapseBuilder {
-        WaveformCollapseBuilder::new(new_depth, Some(builder))
-    }
-
-    fn build(&mut self) {
-        let mut rng = RandomNumberGenerator::new();
-
         const CHUNK_SIZE: i32 = 8;
+        build_data.take_snapshot();
 
-        let prebuilder = &mut self.derive_from.as_mut().unwrap();
+        let patterns = build_patterns(&build_data.map, CHUNK_SIZE, true, true);
-        prebuilder.build_map();
-        self.map = prebuilder.get_map();
-        for t in self.map.tiles.iter_mut() {
-            if *t == TileType::DownStairs {
-                *t = TileType::Floor
-            }
-        }
-        self.take_snapshot();
-
-        let patterns = build_patterns(&self.map, CHUNK_SIZE, true, true);
         let constraints = patterns_to_constraints(patterns, CHUNK_SIZE);
-        self.render_tile_gallery(&constraints, CHUNK_SIZE);
+        self.render_tile_gallery(&constraints, CHUNK_SIZE, build_data);
 
-        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);
+            let mut solver = Solver::new(constraints.clone(), CHUNK_SIZE, &build_data.map);
-            while !solver.iteration(&mut self.map, &mut rng) {
+            while !solver.iteration(&mut build_data.map, rng) {
-                self.take_snapshot();
+                build_data.take_snapshot();
             }
-            self.take_snapshot();
+            build_data.take_snapshot();
             if solver.possible {
                 break;
             } // If it has hit an impossible condition, try again
         }
 
-        // Find a starting point; start at the middle and walk left until we find an open tile
+        build_data.spawn_list.clear();
-        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::DownStairs;
-        self.take_snapshot();
-
-        // Now we build a noise map for use in spawning entities later
-        self.noise_areas = generate_voronoi_spawn_regions(&self.map, &mut rng);
-
-        // Spawn the entities
-        for area in self.noise_areas.iter() {
-            spawner::spawn_region(
-                &self.map,
-                &mut rng,
-                area.1,
-                self.depth,
-                &mut self.spawn_list,
-            );
-        }
     }
 
-    fn render_tile_gallery(&mut self, constraints: &[MapChunk], chunk_size: i32) {
+    fn render_tile_gallery(
-        self.map = Map::new(0);
+        &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() {
-            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 {
+            if x + chunk_size > build_data.map.width {
                 // Move to the next row
                 x = 1;
                 y += chunk_size + 1;
 
-                if y + chunk_size > self.map.height {
+                if y + chunk_size > build_data.map.height {
                     // Move to the next page
-                    self.take_snapshot();
+                    build_data.take_snapshot();
-                    self.map = Map::new(0);
+                    build_data.map = Map::new(0);
 
                     x = 1;
                     y = 1;
@@ -182,6 +86,6 @@ impl WaveformCollapseBuilder {
 
             counter += 1;
         }
-        self.take_snapshot();
+        build_data.take_snapshot();
     }
 }