Add straight line corridor builder

src/map_builders.rs

@@ -18,6 +18,7 @@ mod room_exploder;
 mod room_sorter;
 mod rooms_corridors_bsp;
 mod rooms_corridors_dogleg;
+mod rooms_corridors_lines;
 mod rooms_corridors_nearest;
 mod simple_map;
 mod voronoi;
@@ -44,6 +45,7 @@ use room_exploder::RoomExploder;
 use room_sorter::{RoomSort, RoomSorter};
 use rooms_corridors_bsp::BspCorridors;
 use rooms_corridors_dogleg::DoglegCorridors;
+use rooms_corridors_lines::StraightLineCorridors;
 use rooms_corridors_nearest::NearestCorridors;
 use simple_map::SimpleMapBuilder;
 use specs::prelude::*;

src/map_builders/rooms_corridors_lines.rs

@@ -0,0 +1,65 @@
+use super::{BuilderMap, MetaMapBuilder};
+use crate::{Rect, TileType};
+use rltk::RandomNumberGenerator;
+use std::collections::HashSet;
+
+pub struct StraightLineCorridors {}
+
+impl MetaMapBuilder for StraightLineCorridors {
+    #[allow(dead_code)]
+    fn build_map(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
+        self.corridors(rng, build_data);
+    }
+}
+
+impl StraightLineCorridors {
+    #[allow(dead_code)]
+    pub fn new() -> Box<StraightLineCorridors> {
+        Box::new(StraightLineCorridors {})
+    }
+
+    fn corridors(&mut self, _rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
+        let rooms: Vec<Rect>;
+        if let Some(rooms_builder) = &build_data.rooms {
+            rooms = rooms_builder.clone();
+        } else {
+            panic!("Straight Line Corridors require a builder with room structures.");
+        }
+
+        let mut connected: HashSet<usize> = HashSet::new();
+        for (i, room) in rooms.iter().enumerate() {
+            let mut room_distance: Vec<(usize, f32)> = Vec::new();
+            let room_center = room.center();
+            let room_center_pt = rltk::Point::new(room_center.0, room_center.1);
+
+            for (j, other_room) in rooms.iter().enumerate() {
+                if i != j && !connected.contains(&j) {
+                    let other_center = other_room.center();
+                    let other_center_pt = rltk::Point::new(other_center.0, other_center.1);
+                    let distance =
+                        rltk::DistanceAlg::Pythagoras.distance2d(room_center_pt, other_center_pt);
+
+                    room_distance.push((j, distance));
+                }
+            }
+
+            if !room_distance.is_empty() {
+                room_distance.sort_by(|a, b| a.1.partial_cmp(&b.1).unwrap());
+                let dest_center = rooms[room_distance[0].0].center();
+                let line = rltk::line2d(
+                    rltk::LineAlg::Bresenham,
+                    room_center_pt,
+                    rltk::Point::new(dest_center.0, dest_center.1),
+                );
+
+                for cell in line.iter() {
+                    let idx = build_data.map.xy_idx(cell.x, cell.y);
+                    build_data.map.tiles[idx] = TileType::Floor;
+                }
+
+                connected.insert(i);
+                build_data.take_snapshot();
+            }
+        }
+    }
+}