refactor: switch NodeId to u16, use I8Vec2 for grid coordinates

src/game.rs

@@ -11,7 +11,7 @@ use crate::systems::blinking::Blinking;
 use crate::systems::movement::{BufferedDirection, Position, Velocity};
 use crate::systems::profiling::SystemId;
 use crate::systems::render::RenderDirty;
-use crate::systems::{self, ghost_collision_system, present_system, Hidden, MovementModifiers};
+use crate::systems::{self, ghost_collision_system, present_system, Hidden, MovementModifiers, NodeId};
 use crate::systems::{
     audio_system, blinking_system, collision_system, debug_render_system, directional_render_system, dirty_render_system,
     eaten_ghost_system, ghost_movement_system, ghost_state_animation_system, hud_render_system, item_system, profile,
@@ -303,7 +303,7 @@ impl Game {
             .ok_or_else(|| GameError::Texture(TextureError::AtlasTileNotFound("maze/energizer.png".to_string())))?;
 
         // Build a list of item entities to spawn from the map
-        let nodes: Vec<(usize, EntityType, AtlasTile, f32)> = world
+        let nodes: Vec<(NodeId, EntityType, AtlasTile, f32)> = world
             .resource::<Map>()
             .iter_nodes()
             .filter_map(|(id, tile)| match tile {

src/map/builder.rs

@@ -5,7 +5,7 @@ use crate::map::graph::{Graph, Node, TraversalFlags};
 use crate::map::parser::MapTileParser;
 use crate::systems::movement::NodeId;
 use bevy_ecs::resource::Resource;
-use glam::{IVec2, Vec2};
+use glam::{I8Vec2, IVec2, Vec2};
 use std::collections::{HashMap, VecDeque};
 use tracing::debug;
 
@@ -38,7 +38,7 @@ pub struct Map {
     /// Connected graph of navigable positions.
     pub graph: Graph,
     /// Bidirectional mapping between 2D grid coordinates and graph node indices.
-    pub grid_to_node: HashMap<IVec2, NodeId>,
+    pub grid_to_node: HashMap<I8Vec2, NodeId>,
     /// Predetermined spawn locations for all game entities
     pub start_positions: NodePositions,
     /// 2D array of tile types for collision detection and rendering
@@ -76,8 +76,8 @@ impl Map {
         let mut queue = VecDeque::new();
         queue.push_back(start_pos);
         let pos = Vec2::new(
-            (start_pos.x * CELL_SIZE as i32) as f32,
+            (start_pos.x as i32 * CELL_SIZE as i32) as f32,
-            (start_pos.y * CELL_SIZE as i32) as f32,
+            (start_pos.y as i32 * CELL_SIZE as i32) as f32,
         ) + cell_offset;
         let node_id = graph.add_node(Node { position: pos });
         grid_to_node.insert(start_pos, node_id);
@@ -89,9 +89,9 @@ impl Map {
 
                 // Skip if the new position is out of bounds
                 if new_position.x < 0
-                    || new_position.x >= BOARD_CELL_SIZE.x as i32
+                    || new_position.x as i32 >= BOARD_CELL_SIZE.x as i32
                     || new_position.y < 0
-                    || new_position.y >= BOARD_CELL_SIZE.y as i32
+                    || new_position.y as i32 >= BOARD_CELL_SIZE.y as i32
                 {
                     continue;
                 }
@@ -108,8 +108,8 @@ impl Map {
                 ) {
                     // Add the new position to the graph/queue
                     let pos = Vec2::new(
-                        (new_position.x * CELL_SIZE as i32) as f32,
+                        (new_position.x as i32 * CELL_SIZE as i32) as f32,
-                        (new_position.y * CELL_SIZE as i32) as f32,
+                        (new_position.y as i32 * CELL_SIZE as i32) as f32,
                     ) + cell_offset;
                     let new_node_id = graph.add_node(Node { position: pos });
                     grid_to_node.insert(new_position, new_node_id);
@@ -132,7 +132,7 @@ impl Map {
         for (grid_pos, &node_id) in &grid_to_node {
             for dir in Direction::DIRECTIONS {
                 // If the node doesn't have an edge in this direction, look for a neighbor in that direction
-                if graph.adjacency_list[node_id].get(dir).is_none() {
+                if graph.adjacency_list[node_id as usize].get(dir).is_none() {
                     let neighbor = grid_pos + dir.as_ivec2();
                     // If the neighbor exists, connect the node to it
                     if let Some(&neighbor_id) = grid_to_node.get(&neighbor) {
@@ -199,9 +199,9 @@ impl Map {
     /// representing the four key positions within the ghost house structure.
     fn build_house(
         graph: &mut Graph,
-        grid_to_node: &HashMap<IVec2, NodeId>,
+        grid_to_node: &HashMap<I8Vec2, NodeId>,
-        house_door: &[Option<IVec2>; 2],
+        house_door: &[Option<I8Vec2>; 2],
-    ) -> GameResult<(usize, usize, usize, usize)> {
+    ) -> GameResult<(NodeId, NodeId, NodeId, NodeId)> {
         // Calculate the position of the house entrance node
         let (house_entrance_node_id, house_entrance_node_position) = {
             // Translate the grid positions to the actual node ids
@@ -222,10 +222,13 @@ impl Map {
 
             // Calculate the position of the house node
             let (node_id, node_position) = {
-                let left_pos = graph.get_node(*left_node).ok_or(MapError::NodeNotFound(*left_node))?.position;
+                let left_pos = graph
+                    .get_node(*left_node)
+                    .ok_or(MapError::NodeNotFound(*left_node as usize))?
+                    .position;
                 let right_pos = graph
                     .get_node(*right_node)
-                    .ok_or(MapError::NodeNotFound(*right_node))?
+                    .ok_or(MapError::NodeNotFound(*right_node as usize))?
                     .position;
                 let house_node = graph.add_node(Node {
                     position: left_pos.lerp(right_pos, 0.5),
@@ -249,10 +252,10 @@ impl Map {
             // Place the nodes at, above, and below the center position
             let center_node_id = graph.add_node(Node { position: center_pos });
             let top_node_id = graph.add_node(Node {
-                position: center_pos + (Direction::Up.as_ivec2() * (CELL_SIZE as i32 / 2)).as_vec2(),
+                position: center_pos + IVec2::from(Direction::Up.as_ivec2()).as_vec2() * (CELL_SIZE as f32 / 2.0),
             });
             let bottom_node_id = graph.add_node(Node {
-                position: center_pos + (Direction::Down.as_ivec2() * (CELL_SIZE as i32 / 2)).as_vec2(),
+                position: center_pos + IVec2::from(Direction::Down.as_ivec2()).as_vec2() * (CELL_SIZE as f32 / 2.0),
             });
 
             // Connect the center node to the top and bottom nodes
@@ -268,7 +271,7 @@ impl Map {
 
         // Calculate the position of the center line's center node
         let center_line_center_position =
-            house_entrance_node_position + (Direction::Down.as_ivec2() * (3 * CELL_SIZE as i32)).as_vec2();
+            house_entrance_node_position + IVec2::from(Direction::Down.as_ivec2()).as_vec2() * (3.0 * CELL_SIZE as f32);
 
         // Create the center line
         let (center_center_node_id, center_top_node_id) = create_house_line(graph, center_line_center_position)?;
@@ -300,13 +303,13 @@ impl Map {
         // Create the left line
         let (left_center_node_id, _) = create_house_line(
             graph,
-            center_line_center_position + (Direction::Left.as_ivec2() * (CELL_SIZE as i32 * 2)).as_vec2(),
+            center_line_center_position + IVec2::from(Direction::Left.as_ivec2()).as_vec2() * (CELL_SIZE as f32 * 2.0),
         )?;
 
         // Create the right line
         let (right_center_node_id, _) = create_house_line(
             graph,
-            center_line_center_position + (Direction::Right.as_ivec2() * (CELL_SIZE as i32 * 2)).as_vec2(),
+            center_line_center_position + IVec2::from(Direction::Right.as_ivec2()).as_vec2() * (CELL_SIZE as f32 * 2.0),
         )?;
 
         debug!("Left center node id: {left_center_node_id}");
@@ -336,8 +339,8 @@ impl Map {
     /// Creates hidden intermediate nodes beyond the visible tunnel entrances and connects them with zero-distance edges for instantaneous traversal.
     fn build_tunnels(
         graph: &mut Graph,
-        grid_to_node: &HashMap<IVec2, NodeId>,
+        grid_to_node: &HashMap<I8Vec2, NodeId>,
-        tunnel_ends: &[Option<IVec2>; 2],
+        tunnel_ends: &[Option<I8Vec2>; 2],
     ) -> GameResult<()> {
         // Create the hidden tunnel nodes
         let left_tunnel_hidden_node_id = {
@@ -353,7 +356,7 @@ impl Map {
                     Direction::Left,
                     Node {
                         position: left_tunnel_entrance_node.position
-                            + (Direction::Left.as_ivec2() * (CELL_SIZE as i32 * 2)).as_vec2(),
+                            + IVec2::from(Direction::Left.as_ivec2()).as_vec2() * (CELL_SIZE as f32 * 2.0),
                     },
                 )
                 .map_err(|e| {
@@ -378,7 +381,7 @@ impl Map {
                     Direction::Right,
                     Node {
                         position: right_tunnel_entrance_node.position
-                            + (Direction::Right.as_ivec2() * (CELL_SIZE as i32 * 2)).as_vec2(),
+                            + IVec2::from(Direction::Right.as_ivec2()).as_vec2() * (CELL_SIZE as f32 * 2.0),
                     },
                 )
                 .map_err(|e| {

src/map/direction.rs

@@ -1,4 +1,4 @@
-use glam::IVec2;
+use glam::I8Vec2;
 use strum_macros::AsRefStr;
 
 /// The four cardinal directions.
@@ -28,8 +28,8 @@ impl Direction {
         }
     }
 
-    /// Returns the direction as an IVec2.
+    /// Returns the direction as an I8Vec2.
-    pub fn as_ivec2(self) -> IVec2 {
+    pub fn as_ivec2(self) -> I8Vec2 {
         self.into()
     }
 
@@ -45,13 +45,13 @@ impl Direction {
     }
 }
 
-impl From<Direction> for IVec2 {
+impl From<Direction> for I8Vec2 {
     fn from(dir: Direction) -> Self {
         match dir {
-            Direction::Up => -IVec2::Y,
+            Direction::Up => -I8Vec2::Y,
-            Direction::Down => IVec2::Y,
+            Direction::Down => I8Vec2::Y,
-            Direction::Left => -IVec2::X,
+            Direction::Left => -I8Vec2::X,
-            Direction::Right => IVec2::X,
+            Direction::Right => I8Vec2::X,
         }
     }
 }

src/map/graph.rs

@@ -107,7 +107,7 @@ impl Graph {
 
     /// Adds a new node with the given data to the graph and returns its ID.
     pub fn add_node(&mut self, data: Node) -> NodeId {
-        let id = self.nodes.len();
+        let id = self.nodes.len() as NodeId;
         self.nodes.push(data);
         self.adjacency_list.push(Intersection::default());
         id
@@ -129,10 +129,10 @@ impl Graph {
         distance: Option<f32>,
         direction: Direction,
     ) -> Result<(), &'static str> {
-        if from >= self.adjacency_list.len() {
+        if from as usize >= self.adjacency_list.len() {
             return Err("From node does not exist.");
         }
-        if to >= self.adjacency_list.len() {
+        if to as usize >= self.adjacency_list.len() {
             return Err("To node does not exist.");
         }
 
@@ -178,8 +178,8 @@ impl Graph {
                 }
                 None => {
                     // If no distance is provided, calculate it based on the positions of the nodes
-                    let from_pos = self.nodes[from].position;
+                    let from_pos = self.nodes[from as usize].position;
-                    let to_pos = self.nodes[to].position;
+                    let to_pos = self.nodes[to as usize].position;
                     from_pos.distance(to_pos)
                 }
             },
@@ -187,11 +187,11 @@ impl Graph {
             traversal_flags,
         };
 
-        if from >= self.adjacency_list.len() {
+        if from as usize >= self.adjacency_list.len() {
             return Err("From node does not exist.");
         }
 
-        let adjacency_list = &mut self.adjacency_list[from];
+        let adjacency_list = &mut self.adjacency_list[from as usize];
 
         // Check if the edge already exists in this direction or to the same target
         if let Some(err) = adjacency_list.edges().find_map(|e| {
@@ -215,7 +215,7 @@ impl Graph {
 
     /// Retrieves an immutable reference to a node's data.
     pub fn get_node(&self, id: NodeId) -> Option<&Node> {
-        self.nodes.get(id)
+        self.nodes.get(id as usize)
     }
 
     /// Returns an iterator over all nodes in the graph.
@@ -228,17 +228,17 @@ impl Graph {
         self.adjacency_list
             .iter()
             .enumerate()
-            .flat_map(|(node_id, intersection)| intersection.edges().map(move |edge| (node_id, edge)))
+            .flat_map(|(node_id, intersection)| intersection.edges().map(move |edge| (node_id as NodeId, edge)))
     }
 
     /// Finds a specific edge from a source node to a target node.
     pub fn find_edge(&self, from: NodeId, to: NodeId) -> Option<Edge> {
-        self.adjacency_list.get(from)?.edges().find(|edge| edge.target == to)
+        self.adjacency_list.get(from as usize)?.edges().find(|edge| edge.target == to)
     }
 
     /// Finds an edge originating from a given node that follows a specific direction.
     pub fn find_edge_in_direction(&self, from: NodeId, direction: Direction) -> Option<Edge> {
-        self.adjacency_list.get(from)?.get(direction)
+        self.adjacency_list.get(from as usize)?.get(direction)
     }
 }
 

src/map/parser.rs

@@ -2,7 +2,7 @@
 
 use crate::constants::{MapTile, BOARD_CELL_SIZE};
 use crate::error::ParseError;
-use glam::IVec2;
+use glam::I8Vec2;
 
 /// Structured representation of parsed ASCII board layout with extracted special positions.
 ///
@@ -15,11 +15,11 @@ pub struct ParsedMap {
     /// 2D array of tiles converted from ASCII characters
     pub tiles: [[MapTile; BOARD_CELL_SIZE.y as usize]; BOARD_CELL_SIZE.x as usize],
     /// Two positions marking the ghost house entrance (represented by '=' characters)
-    pub house_door: [Option<IVec2>; 2],
+    pub house_door: [Option<I8Vec2>; 2],
     /// Two positions marking tunnel portals for wraparound teleportation ('T' characters)
-    pub tunnel_ends: [Option<IVec2>; 2],
+    pub tunnel_ends: [Option<I8Vec2>; 2],
     /// Starting position for Pac-Man (marked by 'X' character in the layout)
-    pub pacman_start: Option<IVec2>,
+    pub pacman_start: Option<I8Vec2>,
 }
 
 /// Parser for converting raw board layouts into structured map data.
@@ -88,7 +88,7 @@ impl MapTileParser {
         let mut tiles = [[MapTile::Empty; BOARD_CELL_SIZE.y as usize]; BOARD_CELL_SIZE.x as usize];
         let mut house_door = [None; 2];
         let mut tunnel_ends = [None; 2];
-        let mut pacman_start: Option<IVec2> = None;
+        let mut pacman_start: Option<I8Vec2> = None;
 
         for (y, line) in raw_board.iter().enumerate().take(BOARD_CELL_SIZE.y as usize) {
             for (x, character) in line.chars().enumerate().take(BOARD_CELL_SIZE.x as usize) {
@@ -98,16 +98,16 @@ impl MapTileParser {
                 match tile {
                     MapTile::Tunnel => {
                         if tunnel_ends[0].is_none() {
-                            tunnel_ends[0] = Some(IVec2::new(x as i32, y as i32));
+                            tunnel_ends[0] = Some(I8Vec2::new(x as i8, y as i8));
                         } else {
-                            tunnel_ends[1] = Some(IVec2::new(x as i32, y as i32));
+                            tunnel_ends[1] = Some(I8Vec2::new(x as i8, y as i8));
                         }
                     }
                     MapTile::Wall if character == '=' => {
                         if house_door[0].is_none() {
-                            house_door[0] = Some(IVec2::new(x as i32, y as i32));
+                            house_door[0] = Some(I8Vec2::new(x as i8, y as i8));
                         } else {
-                            house_door[1] = Some(IVec2::new(x as i32, y as i32));
+                            house_door[1] = Some(I8Vec2::new(x as i8, y as i8));
                         }
                     }
                     _ => {}
@@ -115,7 +115,7 @@ impl MapTileParser {
 
                 // Track Pac-Man's starting position
                 if character == 'X' {
-                    pacman_start = Some(IVec2::new(x as i32, y as i32));
+                    pacman_start = Some(I8Vec2::new(x as i8, y as i8));
                 }
 
                 tiles[x][y] = tile;

src/systems/debug.rs

@@ -3,7 +3,7 @@ use std::cmp::Ordering;
 
 use crate::constants::BOARD_PIXEL_OFFSET;
 use crate::map::builder::Map;
-use crate::systems::{Collider, CursorPosition, Position, SystemTimings};
+use crate::systems::{Collider, CursorPosition, NodeId, Position, SystemTimings};
 use bevy_ecs::resource::Resource;
 use bevy_ecs::system::{NonSendMut, Query, Res};
 use glam::{IVec2, UVec2, Vec2};
@@ -185,7 +185,7 @@ pub fn debug_render_system(
 
             // Render node ID if a node is highlighted
             if let Some(closest_node_id) = closest_node {
-                let node = map.graph.get_node(closest_node_id).unwrap();
+                let node = map.graph.get_node(closest_node_id as NodeId).unwrap();
                 let pos = transform_position_with_offset(node.position, scale);
 
                 let surface = font

src/systems/ghost.rs

@@ -36,7 +36,7 @@ pub fn ghost_movement_system(
         loop {
             match *position {
                 Position::Stopped { node: current_node } => {
-                    let intersection = &map.graph.adjacency_list[current_node];
+                    let intersection = &map.graph.adjacency_list[current_node as usize];
                     let opposite = velocity.direction.opposite();
 
                     let mut non_opposite_options: SmallVec<[Edge; 3]> = SmallVec::new();
@@ -159,8 +159,11 @@ pub fn eaten_ghost_system(
                     velocity.direction = direction;
                     *position = Position::Moving {
                         from: current_node,
-                        to: map.graph.adjacency_list[current_node].get(direction).unwrap().target,
+                        to: map.graph.adjacency_list[current_node as usize].get(direction).unwrap().target,
-                        remaining_distance: map.graph.adjacency_list[current_node].get(direction).unwrap().distance,
+                        remaining_distance: map.graph.adjacency_list[current_node as usize]
+                            .get(direction)
+                            .unwrap()
+                            .distance,
                     };
                 }
             }
@@ -186,8 +189,8 @@ pub fn eaten_ghost_system(
                             velocity.direction = next_direction;
                             *position = Position::Moving {
                                 from: to,
-                                to: map.graph.adjacency_list[to].get(next_direction).unwrap().target,
+                                to: map.graph.adjacency_list[to as usize].get(next_direction).unwrap().target,
-                                remaining_distance: map.graph.adjacency_list[to].get(next_direction).unwrap().distance,
+                                remaining_distance: map.graph.adjacency_list[to as usize].get(next_direction).unwrap().distance,
                             };
                         }
                     }
@@ -202,7 +205,11 @@ pub fn eaten_ghost_system(
 
 /// Helper function to find the direction from a node towards a target node.
 /// Uses simple greedy pathfinding - prefers straight lines when possible.
-fn find_direction_to_target(map: &Map, from_node: usize, target_node: usize) -> Option<Direction> {
+fn find_direction_to_target(
+    map: &Map,
+    from_node: crate::systems::movement::NodeId,
+    target_node: crate::systems::movement::NodeId,
+) -> Option<Direction> {
     let from_pos = map.graph.get_node(from_node).unwrap().position;
     let target_pos = map.graph.get_node(target_node).unwrap().position;
 
@@ -224,7 +231,7 @@ fn find_direction_to_target(map: &Map, from_node: usize, target_node: usize) ->
 
     // Return first available direction towards target
     for direction in preferred_dirs {
-        if let Some(edge) = map.graph.adjacency_list[from_node].get(direction) {
+        if let Some(edge) = map.graph.adjacency_list[from_node as usize].get(direction) {
             if edge.traversal_flags.contains(TraversalFlags::GHOST) {
                 return Some(direction);
             }

src/systems/movement.rs

@@ -8,7 +8,7 @@ use glam::Vec2;
 ///
 /// Nodes represent discrete movement targets in the maze. The index directly corresponds to the node's position in the
 /// graph's internal storage arrays.
-pub type NodeId = usize;
+pub type NodeId = u16;
 
 /// A component that represents the speed and cardinal direction of an entity.
 /// Speed is static, only applied when the entity has an edge to traverse.
@@ -57,7 +57,7 @@ impl Position {
         let pos = match &self {
             Position::Stopped { node } => {
                 // Entity is stationary at a node
-                let node = graph.get_node(*node).ok_or(EntityError::NodeNotFound(*node))?;
+                let node = graph.get_node(*node).ok_or(EntityError::NodeNotFound(*node as usize))?;
                 node.position
             }
             Position::Moving {
@@ -66,11 +66,12 @@ impl Position {
                 remaining_distance,
             } => {
                 // Entity is traveling between nodes
-                let from_node = graph.get_node(*from).ok_or(EntityError::NodeNotFound(*from))?;
+                let from_node = graph.get_node(*from).ok_or(EntityError::NodeNotFound(*from as usize))?;
-                let to_node = graph.get_node(*to).ok_or(EntityError::NodeNotFound(*to))?;
+                let to_node = graph.get_node(*to).ok_or(EntityError::NodeNotFound(*to as usize))?;
-                let edge = graph
+                let edge = graph.find_edge(*from, *to).ok_or(EntityError::EdgeNotFound {
-                    .find_edge(*from, *to)
+                    from: *from as usize,
-                    .ok_or(EntityError::EdgeNotFound { from: *from, to: *to })?;
+                    to: *to as usize,
+                })?;
 
                 // For zero-distance edges (tunnels), progress >= 1.0 means we're at the target
                 if edge.distance == 0.0 {

tests/collision.rs

@@ -5,7 +5,8 @@ use pacman::{
     events::GameEvent,
     map::builder::Map,
     systems::{
-        check_collision, collision_system, Collider, EntityType, Ghost, GhostCollider, ItemCollider, PacmanCollider, Position,
+        check_collision, collision_system, Collider, EntityType, Ghost, GhostCollider, ItemCollider, NodeId, PacmanCollider,
+        Position,
     },
 };
 
@@ -59,7 +60,7 @@ fn spawn_test_ghost(world: &mut World) -> Entity {
 fn spawn_test_ghost_at_node(world: &mut World, node: usize) -> Entity {
     world
         .spawn((
-            Position::Stopped { node },
+            Position::Stopped { node: node as NodeId },
             Collider { size: 12.0 },
             GhostCollider,
             Ghost::Blinky,

tests/direction.rs

@@ -1,4 +1,4 @@
-use glam::IVec2;
+use glam::I8Vec2;
 use pacman::map::direction::*;
 
 #[test]
@@ -18,14 +18,14 @@ fn test_direction_opposite() {
 #[test]
 fn test_direction_as_ivec2() {
     let test_cases = [
-        (Direction::Up, -IVec2::Y),
+        (Direction::Up, -I8Vec2::Y),
-        (Direction::Down, IVec2::Y),
+        (Direction::Down, I8Vec2::Y),
-        (Direction::Left, -IVec2::X),
+        (Direction::Left, -I8Vec2::X),
-        (Direction::Right, IVec2::X),
+        (Direction::Right, I8Vec2::X),
     ];
 
     for (dir, expected) in test_cases {
         assert_eq!(dir.as_ivec2(), expected);
-        assert_eq!(IVec2::from(dir), expected);
+        assert_eq!(I8Vec2::from(dir), expected);
     }
 }

tests/map_builder.rs

@@ -26,8 +26,10 @@ fn test_map_node_positions() {
 
     for (grid_pos, &node_id) in &map.grid_to_node {
         let node = map.graph.get_node(node_id).unwrap();
-        let expected_pos = Vec2::new((grid_pos.x * CELL_SIZE as i32) as f32, (grid_pos.y * CELL_SIZE as i32) as f32)
+        let expected_pos = Vec2::new(
-            + Vec2::splat(CELL_SIZE as f32 / 2.0);
+            (grid_pos.x as i32 * CELL_SIZE as i32) as f32,
+            (grid_pos.y as i32 * CELL_SIZE as i32) as f32,
+        ) + Vec2::splat(CELL_SIZE as f32 / 2.0);
 
         assert_eq!(node.position, expected_pos);
     }