Add constraints and common submodules to waveform_collapse map builder

src/map.rs

@@ -7,7 +7,7 @@ pub const MAP_WIDTH: usize = 80;
 pub const MAP_HEIGHT: usize = 43;
 pub const MAP_COUNT: usize = MAP_HEIGHT * MAP_WIDTH;
 
-#[derive(PartialEq, Copy, Clone, Serialize, Deserialize)]
+#[derive(PartialEq, Eq, Hash, Copy, Clone, Serialize, Deserialize)]
 pub enum TileType {
     Wall,
     Floor,

src/map_builders/waveform_collapse/common.rs

@@ -0,0 +1,13 @@
+use crate::TileType;
+
+#[derive(PartialEq, Eq, Hash, Clone)]
+pub struct MapChunk {
+    pub pattern: Vec<TileType>,
+    pub exits: [Vec<bool>; 4],
+    pub has_exits: bool,
+    pub compatible_with: [Vec<usize>; 4],
+}
+
+pub fn tile_idx_in_chunk(chunk_size: i32, x: i32, y: i32) -> usize {
+    ((y * chunk_size) + x) as usize
+}

src/map_builders/waveform_collapse/constraints.rs

@@ -0,0 +1,226 @@
+use super::MapChunk;
+use crate::map_builders::waveform_collapse::common::tile_idx_in_chunk;
+use crate::{Map, TileType};
+use std::collections::HashSet;
+
+pub fn build_patterns(
+    map: &Map,
+    chunk_size: i32,
+    include_flipping: bool,
+    dedupe: bool,
+) -> Vec<Vec<TileType>> {
+    let chunks_x = map.width / chunk_size;
+    let chunks_y = map.height / chunk_size;
+    let mut patterns = Vec::new();
+
+    for cy in 0..chunks_y {
+        for cx in 0..chunks_x {
+            // Normal orientation
+            let mut pattern: Vec<TileType> = Vec::new();
+            let start_x = cx * chunk_size;
+            let end_x = (cx + 1) * chunk_size;
+            let start_y = cy * chunk_size;
+            let end_y = (cy + 1) * chunk_size;
+
+            for y in start_y..end_y {
+                for x in start_x..end_x {
+                    let idx = map.xy_idx(x, y);
+                    pattern.push(map.tiles[idx]);
+                }
+            }
+            patterns.push(pattern);
+
+            if include_flipping {
+                // Flip horizontal
+                pattern = Vec::new();
+                for y in start_y..end_y {
+                    for x in start_x..end_x {
+                        let idx = map.xy_idx(end_x - (x + 1), y);
+                        pattern.push(map.tiles[idx]);
+                    }
+                }
+                patterns.push(pattern);
+
+                // Flip vertical
+                pattern = Vec::new();
+                for y in start_y..end_y {
+                    for x in start_x..end_x {
+                        let idx = map.xy_idx(x, end_y - (y + 1));
+                        pattern.push(map.tiles[idx]);
+                    }
+                }
+                patterns.push(pattern);
+
+                // Flip both
+                pattern = Vec::new();
+                for y in start_y..end_y {
+                    for x in start_x..end_x {
+                        let idx = map.xy_idx(end_x - (x + 1), end_y - (y + 1));
+                        pattern.push(map.tiles[idx]);
+                    }
+                }
+                patterns.push(pattern);
+            }
+        }
+    }
+
+    // Dedupe
+    if dedupe {
+        rltk::console::log(format!(
+            "Pre de-duplication, there are {} patterns",
+            patterns.len()
+        ));
+
+        // Use a set to de-duplicate
+        let set: HashSet<Vec<TileType>> = patterns.drain(..).collect();
+        patterns.extend(set.into_iter());
+
+        rltk::console::log(format!("There are {} patterns", patterns.len()));
+    }
+
+    patterns
+}
+
+pub fn render_pattern_to_map(
+    map: &mut Map,
+    chunk: &MapChunk,
+    chunk_size: i32,
+    start_x: i32,
+    start_y: i32,
+) {
+    let mut i = 0_usize;
+    for tile_y in 0..chunk_size {
+        for tile_x in 0..chunk_size {
+            let map_idx = map.xy_idx(start_x + tile_x, start_y + tile_y);
+            map.tiles[map_idx] = chunk.pattern[i];
+            map.visible_tiles[map_idx] = true;
+
+            i += 1;
+        }
+    }
+
+    for (x, northbound) in chunk.exits[0].iter().enumerate() {
+        if *northbound {
+            let map_idx = map.xy_idx(start_x + x as i32, start_y);
+            map.tiles[map_idx] = TileType::DownStairs;
+        }
+    }
+    for (x, southbound) in chunk.exits[1].iter().enumerate() {
+        if *southbound {
+            let map_idx = map.xy_idx(start_x + x as i32, start_y + chunk_size - 1);
+            map.tiles[map_idx] = TileType::DownStairs;
+        }
+    }
+    for (x, westbound) in chunk.exits[2].iter().enumerate() {
+        if *westbound {
+            let map_idx = map.xy_idx(start_x, start_y + x as i32);
+            map.tiles[map_idx] = TileType::DownStairs;
+        }
+    }
+    for (x, eastbound) in chunk.exits[3].iter().enumerate() {
+        if *eastbound {
+            let map_idx = map.xy_idx(start_x + chunk_size - 1, start_y + x as i32);
+            map.tiles[map_idx] = TileType::DownStairs;
+        }
+    }
+}
+
+pub fn patterns_to_constraints(patterns: Vec<Vec<TileType>>, chunk_size: i32) -> Vec<MapChunk> {
+    // Move into the new constraints object
+    let mut constraints: Vec<MapChunk> = Vec::new();
+    for p in patterns {
+        let mut new_chunk = MapChunk {
+            pattern: p,
+            exits: [Vec::new(), Vec::new(), Vec::new(), Vec::new()],
+            has_exits: true,
+            compatible_with: [Vec::new(), Vec::new(), Vec::new(), Vec::new()],
+        };
+        for exit in new_chunk.exits.iter_mut() {
+            for _i in 0..chunk_size {
+                exit.push(false);
+            }
+        }
+
+        let mut n_exits = 0;
+        for x in 0..chunk_size {
+            // Check for north-bound exits
+            let north_idx = tile_idx_in_chunk(chunk_size, x, 0);
+            if new_chunk.pattern[north_idx] == TileType::Floor {
+                new_chunk.exits[0][x as usize] = true;
+                n_exits += 1;
+            }
+
+            // Check for south-bound exits
+            let south_idx = tile_idx_in_chunk(chunk_size, x, chunk_size - 1);
+            if new_chunk.pattern[south_idx] == TileType::Floor {
+                new_chunk.exits[1][x as usize] = true;
+                n_exits += 1;
+            }
+
+            // Check for west-bound exits
+            let west_idx = tile_idx_in_chunk(chunk_size, 0, x);
+            if new_chunk.pattern[west_idx] == TileType::Floor {
+                new_chunk.exits[2][x as usize] = true;
+                n_exits += 1;
+            }
+
+            // Check for east-bound exits
+            let east_idx = tile_idx_in_chunk(chunk_size, chunk_size - 1, x);
+            if new_chunk.pattern[east_idx] == TileType::Floor {
+                new_chunk.exits[3][x as usize] = true;
+                n_exits += 1;
+            }
+        }
+
+        if n_exits == 0 {
+            new_chunk.has_exits = false;
+        }
+
+        constraints.push(new_chunk);
+    }
+
+    // Build compatibility matrix
+    let ch = constraints.clone();
+    for c in constraints.iter_mut() {
+        for (j, potential) in ch.iter().enumerate() {
+            // If there are no exits at all, it's compatible
+            if !c.has_exits || !potential.has_exits {
+                for compat in c.compatible_with.iter_mut() {
+                    compat.push(j);
+                }
+            } else {
+                // Evaluate compatibility by direction
+                for (direction, exit_list) in c.exits.iter_mut().enumerate() {
+                    let opposite = match direction {
+                        0 => 1, // Our North, Their South
+                        1 => 0, // Our South, Their North
+                        2 => 3, // Our West, Their East
+                        _ => 2, // Our East, Their West
+                    };
+
+                    let mut it_fits = false;
+                    let mut has_any = false;
+                    for (slot, can_enter) in exit_list.iter().enumerate() {
+                        if *can_enter {
+                            has_any = true;
+                            if potential.exits[opposite][slot] {
+                                it_fits = true;
+                            }
+                        }
+                    }
+                    if it_fits {
+                        c.compatible_with[direction].push(j);
+                    }
+                    if !has_any {
+                        // There's no exits on this side, we don't care what goes there
+                        for compat in c.compatible_with.iter_mut() {
+                            compat.push(j);
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    constraints
+}

src/map_builders/waveform_collapse/image_loader.rs

@@ -1,5 +1,5 @@
-use rltk::rex::XpFile;
 use crate::{Map, TileType};
+use rltk::rex::XpFile;
 
 /// Loads a RexPaint file, and converts it into our map format
 pub fn load_rex_map(new_depth: i32, xp_file: &XpFile) -> Map {