feat: courtyard layout generation for BSP 2

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pxl8d/src/main.rs

@@ -6,6 +6,7 @@ extern crate alloc;
 use pxl8d::*;
 use pxl8d::chunk::ChunkId;
 use pxl8d::chunk::stream::ClientChunkState;
+use pxl8d::procgen::LayoutMode;
 
 const TICK_RATE: u64 = 30;
 const TICK_NS: u64 = 1_000_000_000 / TICK_RATE;
@@ -126,9 +127,8 @@ pub extern "C" fn main(_argc: i32, _argv: *const *const u8) -> i32 {
                                     width: 20,
                                     height: 20,
                                     seed: 12345u32.wrapping_add(2),
-                                    min_room_size: 14,
-                                    max_room_size: 16,
-                                    num_rooms: 1,
+                                    layout: LayoutMode::Courtyard,
+                                    ..ProcgenParams::default()
                                 }),
                                 _ => None,
                             };

pxl8d/src/procgen.rs

@@ -19,6 +19,12 @@ pub struct LightSource {
     pub radius: f32,
 }
 
+#[derive(Clone, Copy, PartialEq)]
+pub enum LayoutMode {
+    Dungeon,
+    Courtyard,
+}
+
 #[derive(Clone, Copy)]
 pub struct ProcgenParams {
     pub width: i32,
@@ -27,6 +33,7 @@ pub struct ProcgenParams {
     pub min_room_size: i32,
     pub max_room_size: i32,
     pub num_rooms: i32,
+    pub layout: LayoutMode,
 }
 
 impl Default for ProcgenParams {
@@ -38,6 +45,7 @@ impl Default for ProcgenParams {
             min_room_size: 3,
             max_room_size: 6,
             num_rooms: 8,
+            layout: LayoutMode::Dungeon,
         }
     }
 }
@@ -1074,6 +1082,144 @@ pub fn generate_rooms(params: &ProcgenParams) -> Bsp {
     bsp.into()
 }
 
-pub fn generate(params: &ProcgenParams) -> Bsp {
-    generate_rooms(params)
+pub fn generate_courtyard(params: &ProcgenParams) -> Bsp {
+    let mut rng = Rng::new(params.seed);
+    let mut grid = RoomGrid::new(params.width, params.height);
+    grid.fill(1);
+
+    let mut rooms: Vec<Bounds> = Vec::new();
+
+    let cx = params.width / 2;
+    let cy = params.height / 2;
+    let court_half = 4;
+    let court_x = cx - court_half;
+    let court_y = cy - court_half;
+    let court_w = court_half * 2;
+    let court_h = court_half * 2;
+
+    for ry in court_y..(court_y + court_h) {
+        for rx in court_x..(court_x + court_w) {
+            grid.set(rx, ry, 0);
+        }
+    }
+    rooms.push(Bounds { x: court_x, y: court_y, w: court_w, h: court_h });
+
+    let wing_dirs: [(i32, i32); 4] = [(0, -1), (0, 1), (-1, 0), (1, 0)];
+
+    for &(dx, dy) in &wing_dirs {
+        let room_w = 3 + (rng.next() % 3) as i32;
+        let room_h = 3 + (rng.next() % 3) as i32;
+
+        let (rx, ry) = if dx != 0 {
+            let rx = if dx > 0 { court_x + court_w + 2 } else { court_x - room_w - 2 };
+            let ry = cy - room_h / 2;
+            (rx, ry)
+        } else {
+            let rx = cx - room_w / 2;
+            let ry = if dy > 0 { court_y + court_h + 2 } else { court_y - room_h - 2 };
+            (rx, ry)
+        };
+
+        let rx = rx.max(1).min(params.width - room_w - 1);
+        let ry = ry.max(1).min(params.height - room_h - 1);
+
+        for y in ry..(ry + room_h) {
+            for x in rx..(rx + room_w) {
+                grid.set(x, y, 0);
+            }
+        }
+
+        let room_cx = rx + room_w / 2;
+        let room_cy = ry + room_h / 2;
+        if dx != 0 {
+            carve_corridor_h(&mut grid, cx, room_cx, room_cy);
+        } else {
+            carve_corridor_v(&mut grid, cy, room_cy, room_cx);
+        }
+
+        let primary = Bounds { x: rx, y: ry, w: room_w, h: room_h };
+        rooms.push(primary);
+
+        let extra_count = 1 + (rng.next() % 2) as i32;
+        for _ in 0..extra_count {
+            let ew = 2 + (rng.next() % 3) as i32;
+            let eh = 2 + (rng.next() % 3) as i32;
+
+            let (ex, ey) = if dx != 0 {
+                let ex = if dx > 0 { rx + room_w + 1 } else { rx - ew - 1 };
+                let ey = ry + (rng.next() % room_h.max(1) as u32) as i32 - eh / 2;
+                (ex, ey)
+            } else {
+                let ex = rx + (rng.next() % room_w.max(1) as u32) as i32 - ew / 2;
+                let ey = if dy > 0 { ry + room_h + 1 } else { ry - eh - 1 };
+                (ex, ey)
+            };
+
+            let ex = ex.max(1).min(params.width - ew - 1);
+            let ey = ey.max(1).min(params.height - eh - 1);
+
+            for y in ey..(ey + eh) {
+                for x in ex..(ex + ew) {
+                    grid.set(x, y, 0);
+                }
+            }
+
+            let ecx = ex + ew / 2;
+            let ecy = ey + eh / 2;
+            if rng.next() % 2 == 0 {
+                carve_corridor_h(&mut grid, room_cx, ecx, room_cy);
+                carve_corridor_v(&mut grid, room_cy, ecy, ecx);
+            } else {
+                carve_corridor_v(&mut grid, room_cy, ecy, room_cx);
+                carve_corridor_h(&mut grid, room_cx, ecx, ecy);
+            }
+
+            rooms.push(Bounds { x: ex, y: ey, w: ew, h: eh });
+        }
+    }
+
+    let mut bsp = BspBuilder::new();
+    grid_to_bsp(&mut bsp, &grid);
+
+    let light_height = 80.0;
+    let fireball_pos = Vec3::new(384.0, light_height, 324.0);
+    let fireball_exclusion_radius = 150.0;
+
+    let lights: Vec<LightSource> = rooms.iter().filter_map(|room| {
+        let room_cx = (room.x as f32 + room.w as f32 / 2.0) * CELL_SIZE;
+        let room_cz = (room.y as f32 + room.h as f32 / 2.0) * CELL_SIZE;
+
+        let ddx = room_cx - fireball_pos.x;
+        let ddz = room_cz - fireball_pos.z;
+        if ddx * ddx + ddz * ddz < fireball_exclusion_radius * fireball_exclusion_radius {
+            return None;
+        }
+
+        let intensity = if room.w >= 6 && room.h >= 6 { 2.0 } else { 1.5 };
+        let radius = if room.w >= 6 && room.h >= 6 { 250.0 } else { 160.0 };
+
+        Some(LightSource {
+            position: Vec3::new(room_cx, light_height, room_cz),
+            intensity,
+            radius,
+        })
+    }).collect();
+
+    let mut lights = lights;
+    lights.push(LightSource {
+        position: Vec3::new(860.0, light_height, 416.0),
+        intensity: 1.2,
+        radius: 120.0,
+    });
+
+    compute_bsp_vertex_lighting(&mut bsp, &lights);
+
+    bsp.into()
+}
+
+pub fn generate(params: &ProcgenParams) -> Bsp {
+    match params.layout {
+        LayoutMode::Dungeon => generate_rooms(params),
+        LayoutMode::Courtyard => generate_courtyard(params),
+    }
 }