diff --git a/src/layout.rs b/src/layout.rs
new file mode 100644
index 0000000..6296a19
--- /dev/null
+++ b/src/layout.rs
@@ -0,0 +1,134 @@
+#[derive(Debug, Clone)]
+pub struct Room {
+    pub x: usize,
+    pub y: usize,
+    pub width: usize,
+    pub height: usize,
+}
+
+impl Room {
+    pub fn center_cell(&self) -> (usize, usize) {
+        (self.x + (self.width / 2), self.y + (self.height / 2))
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Corridor {
+    pub from: (usize, usize),
+    pub to: (usize, usize),
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct DungeonLayout {
+    pub rooms: Vec<Room>,
+    pub corridors: Vec<Corridor>,
+}
+
+pub fn generate_layout(cols: usize, rows: usize, target_room_count: usize, seed: u64) -> DungeonLayout {
+    let mut rng = SimpleRng::new(seed ^ ((cols as u64) << 32) ^ rows as u64);
+    let mut rooms = Vec::new();
+    let mut corridors = Vec::new();
+
+    let min_room_size = 2;
+    if cols < min_room_size || rows < min_room_size || target_room_count == 0 {
+        return DungeonLayout { rooms, corridors };
+    }
+
+    let max_room_width = (cols / 3).clamp(min_room_size, cols.min(12));
+    let max_room_height = (rows / 3).clamp(min_room_size, rows.min(12));
+    let max_attempts = target_room_count.saturating_mul(40).max(50);
+
+    for _ in 0..max_attempts {
+        if rooms.len() >= target_room_count {
+            break;
+        }
+
+        let width = rng.range_inclusive(min_room_size, max_room_width);
+        let height = rng.range_inclusive(min_room_size, max_room_height);
+        let x = rng.range_inclusive(0, cols - width);
+        let y = rng.range_inclusive(0, rows - height);
+
+        let candidate = Room {
+            x,
+            y,
+            width,
+            height,
+        };
+
+        if rooms
+            .iter()
+            .all(|existing| !overlaps_with_padding(&candidate, existing, 1))
+        {
+            rooms.push(candidate);
+        }
+    }
+
+    for idx in 1..rooms.len() {
+        let a = rooms[idx - 1].center_cell();
+        let b = rooms[idx].center_cell();
+
+        if rng.next_bool() {
+            push_corridor_if_nonzero(&mut corridors, (a.0, a.1), (b.0, a.1));
+            push_corridor_if_nonzero(&mut corridors, (b.0, a.1), (b.0, b.1));
+        } else {
+            push_corridor_if_nonzero(&mut corridors, (a.0, a.1), (a.0, b.1));
+            push_corridor_if_nonzero(&mut corridors, (a.0, b.1), (b.0, b.1));
+        }
+    }
+
+    DungeonLayout { rooms, corridors }
+}
+
+fn overlaps_with_padding(a: &Room, b: &Room, padding: usize) -> bool {
+    let a_left = a.x.saturating_sub(padding);
+    let a_top = a.y.saturating_sub(padding);
+    let a_right = a.x + a.width + padding;
+    let a_bottom = a.y + a.height + padding;
+
+    let b_left = b.x;
+    let b_top = b.y;
+    let b_right = b.x + b.width;
+    let b_bottom = b.y + b.height;
+
+    a_left < b_right && a_right > b_left && a_top < b_bottom && a_bottom > b_top
+}
+
+fn push_corridor_if_nonzero(
+    corridors: &mut Vec<Corridor>,
+    from: (usize, usize),
+    to: (usize, usize),
+) {
+    if from != to {
+        corridors.push(Corridor { from, to });
+    }
+}
+
+struct SimpleRng {
+    state: u64,
+}
+
+impl SimpleRng {
+    fn new(seed: u64) -> Self {
+        let state = if seed == 0 { 0xA5A5_A5A5_1234_5678 } else { seed };
+        Self { state }
+    }
+
+    fn next_u32(&mut self) -> u32 {
+        self.state ^= self.state >> 12;
+        self.state ^= self.state << 25;
+        self.state ^= self.state >> 27;
+        (self.state.wrapping_mul(0x2545_F491_4F6C_DD1D) >> 32) as u32
+    }
+
+    fn next_bool(&mut self) -> bool {
+        (self.next_u32() & 1) == 0
+    }
+
+    fn range_inclusive(&mut self, min: usize, max: usize) -> usize {
+        if min >= max {
+            return min;
+        }
+        let width = max - min + 1;
+        min + (self.next_u32() as usize % width)
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index d12db1b..2a4a29e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,8 @@
+mod layout;
+
 use eframe::egui;
 use egui::{Color32, Stroke};
+use layout::{DungeonLayout, generate_layout};
 
 fn main() -> eframe::Result<()> {
     let options = eframe::NativeOptions::default();
@@ -14,16 +17,33 @@ fn main() -> eframe::Result<()> {
 struct DungeonApp {
     cols: usize,
     rows: usize,
+    room_count: usize,
+    seed: u64,
+    layout: DungeonLayout,
 }
 
 impl Default for DungeonApp {
     fn default() -> Self {
-        Self { cols: 12, rows: 8 }
+        let cols = 24;
+        let rows = 18;
+        let room_count = 8;
+        let seed = 1;
+        let layout = generate_layout(cols, rows, room_count, seed);
+
+        Self {
+            cols,
+            rows,
+            room_count,
+            seed,
+            layout,
+        }
     }
 }
 
 impl eframe::App for DungeonApp {
     fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
+        let mut settings_changed = false;
+
         egui::SidePanel::left("options_panel")
             .resizable(true)
             .min_width(180.0)
@@ -35,36 +55,77 @@ impl eframe::App for DungeonApp {
 
                 ui.label("Columns");
                 ui.horizontal(|ui| {
-                    ui.add(egui::Slider::new(&mut self.cols, 2..=100).show_value(false));
-                    ui.add(
-                        egui::DragValue::new(&mut self.cols)
-                            .speed(1.0)
-                            .range(2..=500),
-                    );
+                    settings_changed |= ui
+                        .add(egui::Slider::new(&mut self.cols, 6..=100).show_value(false))
+                        .changed();
+                    settings_changed |= ui
+                        .add(
+                            egui::DragValue::new(&mut self.cols)
+                                .speed(1.0)
+                                .range(2..=500),
+                        )
+                        .changed();
                 });
 
                 ui.add_space(8.0);
                 ui.label("Rows");
                 ui.horizontal(|ui| {
-                    ui.add(egui::Slider::new(&mut self.rows, 2..=100).show_value(false));
-                    ui.add(
-                        egui::DragValue::new(&mut self.rows)
-                            .speed(1.0)
-                            .range(2..=500),
-                    );
+                    settings_changed |= ui
+                        .add(egui::Slider::new(&mut self.rows, 6..=100).show_value(false))
+                        .changed();
+                    settings_changed |= ui
+                        .add(
+                            egui::DragValue::new(&mut self.rows)
+                                .speed(1.0)
+                                .range(2..=500),
+                        )
+                        .changed();
                 });
+
+                ui.add_space(12.0);
+                ui.heading("Dungeon");
+                ui.add_space(8.0);
+                ui.label("Room Count");
+                ui.horizontal(|ui| {
+                    settings_changed |= ui
+                        .add(egui::Slider::new(&mut self.room_count, 1..=40).show_value(false))
+                        .changed();
+                    settings_changed |= ui
+                        .add(
+                            egui::DragValue::new(&mut self.room_count)
+                                .speed(1.0)
+                                .range(1..=200),
+                        )
+                        .changed();
+                });
+
+                ui.add_space(10.0);
+                if ui.button("Generate New Layout").clicked() {
+                    self.seed = self.seed.wrapping_add(1);
+                    self.layout = generate_layout(self.cols, self.rows, self.room_count, self.seed);
+                }
             });
 
+        if settings_changed {
+            self.layout = generate_layout(self.cols, self.rows, self.room_count, self.seed);
+        }
+
         egui::CentralPanel::default().show(ctx, |ui| {
             let available = ui.available_size_before_wrap();
             let (response, painter) = ui.allocate_painter(available, egui::Sense::hover());
             let canvas = response.rect.shrink(12.0);
-            draw_grid(&painter, canvas, self.cols, self.rows);
+            let geometry = draw_grid(&painter, canvas, self.cols, self.rows);
+            draw_layout(&painter, &geometry, &self.layout);
         });
     }
 }
 
-fn draw_grid(painter: &egui::Painter, area: egui::Rect, cols: usize, rows: usize) {
+struct GridGeometry {
+    rect: egui::Rect,
+    cell_size: f32,
+}
+
+fn draw_grid(painter: &egui::Painter, area: egui::Rect, cols: usize, rows: usize) -> GridGeometry {
     let cols = cols.max(1);
     let rows = rows.max(1);
 
@@ -104,4 +165,62 @@ fn draw_grid(painter: &egui::Painter, area: egui::Rect, cols: usize, rows: usize
             stroke,
         );
     }
+
+    GridGeometry {
+        rect: grid_rect,
+        cell_size,
+    }
+}
+
+fn draw_layout(painter: &egui::Painter, geometry: &GridGeometry, layout: &DungeonLayout) {
+    let room_fill = Color32::from_rgb(70, 120, 160);
+    let room_stroke = Stroke::new(1.0, Color32::from_rgb(35, 65, 95));
+    let corridor_fill = Color32::from_rgb(210, 190, 120);
+
+    for corridor in &layout.corridors {
+        for (col, row) in corridor_cells(corridor.from, corridor.to) {
+            let cell_rect = cell_rect(geometry, col, row);
+            painter.rect_filled(cell_rect, 0.0, corridor_fill);
+        }
+    }
+
+    for room in &layout.rooms {
+        let left = geometry.rect.left() + room.x as f32 * geometry.cell_size;
+        let top = geometry.rect.top() + room.y as f32 * geometry.cell_size;
+        let right = left + room.width as f32 * geometry.cell_size;
+        let bottom = top + room.height as f32 * geometry.cell_size;
+        let room_rect = egui::Rect::from_min_max(egui::pos2(left, top), egui::pos2(right, bottom));
+
+        painter.rect_filled(room_rect, 0.0, room_fill);
+        painter.rect_stroke(room_rect, 0.0, room_stroke, egui::StrokeKind::Middle);
+    }
+}
+
+fn corridor_cells(from: (usize, usize), to: (usize, usize)) -> Vec<(usize, usize)> {
+    let mut cells = Vec::new();
+    if from.0 == to.0 {
+        let x = from.0;
+        let start = from.1.min(to.1);
+        let end = from.1.max(to.1);
+        for y in start..=end {
+            cells.push((x, y));
+        }
+    } else if from.1 == to.1 {
+        let y = from.1;
+        let start = from.0.min(to.0);
+        let end = from.0.max(to.0);
+        for x in start..=end {
+            cells.push((x, y));
+        }
+    }
+    cells
+}
+
+fn cell_rect(geometry: &GridGeometry, col: usize, row: usize) -> egui::Rect {
+    let left = geometry.rect.left() + col as f32 * geometry.cell_size;
+    let top = geometry.rect.top() + row as f32 * geometry.cell_size;
+    egui::Rect::from_min_size(
+        egui::pos2(left, top),
+        egui::vec2(geometry.cell_size, geometry.cell_size),
+    )
 }