Expand Room sorter with more options

src/map_builders.rs

@@ -38,7 +38,7 @@ use room_based_stairs::RoomBasedStairs;
 use room_based_starting_position::RoomBasedStartingPosition;
 use room_corner_rounding::RoomCornerRounder;
 use room_exploder::RoomExploder;
-use room_sorter::RoomSorter;
+use room_sorter::{RoomSort, RoomSorter};
 use rooms_corridors_bsp::BspCorridors;
 use rooms_corridors_dogleg::DoglegCorridors;
 use simple_map::SimpleMapBuilder;
@@ -216,7 +216,7 @@ pub fn random_builder(new_depth: i32, rng: &mut RandomNumberGenerator) -> Builde
 
     builder
         .start_with(BspDungeonBuilder::new())
-        .with(RoomSorter::new())
+        .with(RoomSorter::new(RoomSort::Central))
         .with(BspCorridors::new())
         .with(AreaStartingPosition::new(XStart::Center, YStart::Center))
         .with(CullUnreachable::new())

src/map_builders/room_sorter.rs

@@ -1,8 +1,19 @@
 use rltk::RandomNumberGenerator;
 
 use super::{BuilderMap, MetaMapBuilder};
+use crate::Rect;
 
-pub struct RoomSorter {}
+pub enum RoomSort {
+    LeftMost,
+    RightMost,
+    TopMost,
+    BottomMost,
+    Central,
+}
+
+pub struct RoomSorter {
+    sort_by: RoomSort,
+}
 
 impl MetaMapBuilder for RoomSorter {
     #[allow(dead_code)]
@@ -13,15 +24,36 @@ impl MetaMapBuilder for RoomSorter {
 
 impl RoomSorter {
     #[allow(dead_code)]
-    pub fn new() -> Box<RoomSorter> {
-        Box::new(RoomSorter {})
+    pub fn new(sort_by: RoomSort) -> Box<RoomSorter> {
+        Box::new(RoomSorter { sort_by })
     }
 
     fn sorter(&mut self, _rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
-        build_data
-            .rooms
-            .as_mut()
-            .unwrap()
-            .sort_by(|a, b| a.x1.cmp(&b.x1));
+        let rooms = build_data.rooms.as_mut().unwrap();
+
+        match self.sort_by {
+            RoomSort::LeftMost => rooms.sort_by(|a, b| a.x1.cmp(&b.x1)),
+            RoomSort::RightMost => rooms.sort_by(|a, b| b.x2.cmp(&a.x2)),
+            RoomSort::TopMost => rooms.sort_by(|a, b| a.y1.cmp(&b.y1)),
+            RoomSort::BottomMost => rooms.sort_by(|a, b| b.y2.cmp(&a.y2)),
+            RoomSort::Central => {
+                let map_center =
+                    rltk::Point::new(build_data.map.width / 2, build_data.map.height / 2);
+                let center_sort = |a: &Rect, b: &Rect| {
+                    let a_center = a.center();
+                    let a_center_pt = rltk::Point::new(a_center.0, a_center.1);
+                    let b_center = b.center();
+                    let b_center_pt = rltk::Point::new(b_center.0, b_center.1);
+                    let distance_a =
+                        rltk::DistanceAlg::Pythagoras.distance2d(a_center_pt, map_center);
+                    let distance_b =
+                        rltk::DistanceAlg::Pythagoras.distance2d(b_center_pt, map_center);
+
+                    distance_a.partial_cmp(&distance_b).unwrap()
+                };
+
+                rooms.sort_by(center_sort);
+            }
+        }
     }
 }