feat: debug text rendering of statistics, formatting with tests

Cargo.lock

@@ -316,6 +316,12 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "diff"
+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"
+
 [[package]]
 name = "disqualified"
 version = "1.0.0"
@@ -528,6 +534,12 @@ version = "2.7.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32a282da65faaf38286cf3be983213fcf1d2e2a58700e808f83f4ea9a4804bc0"
 
+[[package]]
+name = "micromap"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18c087666f377f857b49564f8791b481260c67825d6b337e1e38ddf54a985a88"
+
 [[package]]
 name = "nonmax"
 version = "0.5.5"
@@ -553,6 +565,12 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "num-width"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "faede9396d7883a8c9c989e0b53c984bf770defb5cb8ed6c345b4c0566cf32b9"
+
 [[package]]
 name = "once_cell"
 version = "1.21.3"
@@ -575,10 +593,14 @@ dependencies = [
  "glam 0.30.5",
  "lazy_static",
  "libc",
+ "micromap",
+ "num-width",
  "once_cell",
+ "parking_lot",
  "pathfinding",
  "phf",
- "rand 0.9.2",
+ "pretty_assertions",
+ "rand",
  "sdl2",
  "serde",
  "serde_json",
@@ -587,6 +609,7 @@ dependencies = [
  "strum",
  "strum_macros",
  "thiserror",
+ "thousands",
  "tracing",
  "tracing-error",
  "tracing-subscriber",
@@ -638,29 +661,30 @@ dependencies = [
 
 [[package]]
 name = "phf"
-version = "0.11.3"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1fd6780a80ae0c52cc120a26a1a42c1ae51b247a253e4e06113d23d2c2edd078"
+checksum = "913273894cec178f401a31ec4b656318d95473527be05c0752cc41cdc32be8b7"
 dependencies = [
  "phf_macros",
  "phf_shared",
+ "serde",
 ]
 
 [[package]]
 name = "phf_generator"
-version = "0.11.3"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c80231409c20246a13fddb31776fb942c38553c51e871f8cbd687a4cfb5843d"
+checksum = "2cbb1126afed61dd6368748dae63b1ee7dc480191c6262a3b4ff1e29d86a6c5b"
 dependencies = [
+ "fastrand",
  "phf_shared",
- "rand 0.8.5",
 ]
 
 [[package]]
 name = "phf_macros"
-version = "0.11.3"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f84ac04429c13a7ff43785d75ad27569f2951ce0ffd30a3321230db2fc727216"
+checksum = "d713258393a82f091ead52047ca779d37e5766226d009de21696c4e667044368"
 dependencies = [
  "phf_generator",
  "phf_shared",
@@ -671,9 +695,9 @@ dependencies = [
 
 [[package]]
 name = "phf_shared"
-version = "0.11.3"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67eabc2ef2a60eb7faa00097bd1ffdb5bd28e62bf39990626a582201b7a754e5"
+checksum = "06005508882fb681fd97892ecff4b7fd0fee13ef1aa569f8695dae7ab9099981"
 dependencies = [
  "siphasher",
 ]
@@ -699,6 +723,16 @@ dependencies = [
  "portable-atomic",
 ]
 
+[[package]]
+name = "pretty_assertions"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3ae130e2f271fbc2ac3a40fb1d07180839cdbbe443c7a27e1e3c13c5cac0116d"
+dependencies = [
+ "diff",
+ "yansi",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.95"
@@ -723,30 +757,15 @@ version = "5.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
 
-[[package]]
-name = "rand"
-version = "0.8.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
-dependencies = [
- "rand_core 0.6.4",
-]
-
 [[package]]
 name = "rand"
 version = "0.9.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6db2770f06117d490610c7488547d543617b21bfa07796d7a12f6f1bd53850d1"
 dependencies = [
- "rand_core 0.9.3",
+ "rand_core",
 ]
 
-[[package]]
-name = "rand_core"
-version = "0.6.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
-
 [[package]]
 name = "rand_core"
 version = "0.9.3"
@@ -987,24 +1006,30 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "2.0.12"
+version = "2.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "567b8a2dae586314f7be2a752ec7474332959c6460e02bde30d702a66d488708"
+checksum = "0b0949c3a6c842cbde3f1686d6eea5a010516deb7085f79db747562d4102f41e"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "2.0.12"
+version = "2.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f7cf42b4507d8ea322120659672cf1b9dbb93f8f2d4ecfd6e51350ff5b17a1d"
+checksum = "cc5b44b4ab9c2fdd0e0512e6bece8388e214c0749f5862b114cc5b7a25daf227"
 dependencies = [
  "proc-macro2",
  "quote",
  "syn",
 ]
 
+[[package]]
+name = "thousands"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3bf63baf9f5039dadc247375c29eb13706706cfde997d0330d05aa63a77d8820"
+
 [[package]]
 name = "thread_local"
 version = "1.1.7"
@@ -1428,3 +1453,9 @@ checksum = "6f42320e61fe2cfd34354ecb597f86f413484a798ba44a8ca1165c58d42da6c1"
 dependencies = [
  "bitflags 2.9.1",
 ]
+
+[[package]]
+name = "yansi"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfe53a6657fd280eaa890a3bc59152892ffa3e30101319d168b781ed6529b049"

Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-tracing = { version = "0.1.40", features = ["max_level_debug", "release_max_level_debug"]}
+tracing = { version = "0.1.41", features = ["max_level_debug", "release_max_level_debug"]}
 tracing-error = "0.2.0"
 tracing-subscriber = {version = "0.3.17", features = ["env-filter"]}
 lazy_static = "1.5.0"
@@ -15,17 +15,22 @@ spin_sleep = "1.3.2"
 rand = { version = "0.9.2", default-features = false, features = ["small_rng", "os_rng"] }
 pathfinding = "4.14"
 once_cell = "1.21.3"
-thiserror = "2.0"
+thiserror = "2.0.14"
 anyhow = "1.0"
-glam = { version = "0.30.5", features = [] }
+glam = "0.30.5"
 serde = { version = "1.0.219", features = ["derive"] }
 serde_json = "1.0.142"
 smallvec = "1.15.1"
 strum = "0.27.2"
 strum_macros = "0.27.2"
-phf = { version = "0.11", features = ["macros"] }
+phf = { version = "0.12.1", features = ["macros"] }
 bevy_ecs = "0.16.1"
 bitflags = "2.9.1"
+parking_lot = "0.12.3"
+micromap = "0.1.0"
+thousands = "0.2.0"
+pretty_assertions = "1.4.1"
+num-width = "0.1.0"
 
 [profile.release]
 lto = true
@@ -64,4 +69,4 @@ libc = "0.2.175"
 [build-dependencies]
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-phf = { version = "0.11", features = ["macros"] }
+phf = { version = "0.12.1", features = ["macros"] }

src/app.rs

@@ -5,7 +5,6 @@ use sdl2::render::TextureCreator;
 use sdl2::ttf::Sdl2TtfContext;
 use sdl2::video::WindowContext;
 use sdl2::{AudioSubsystem, EventPump, Sdl, VideoSubsystem};
-use tracing::warn;
 
 use crate::error::{GameError, GameResult};
 
@@ -50,7 +49,6 @@ impl App {
             window
                 .into_canvas()
                 .accelerated()
-                .present_vsync()
                 .build()
                 .map_err(|e| GameError::Sdl(e.to_string()))?,
         ));
@@ -64,12 +62,6 @@ impl App {
         let game = Game::new(canvas, texture_creator, event_pump)?;
         // game.audio.set_mute(cfg!(debug_assertions));
 
-        // Initial draw
-        // game.draw(&mut canvas, &mut backbuffer)
-        //     .map_err(|e| GameError::Sdl(e.to_string()))?;
-        // game.present_backbuffer(&mut canvas, &backbuffer, glam::Vec2::ZERO)
-        //     .map_err(|e| GameError::Sdl(e.to_string()))?;
-
         Ok(App {
             game,
             focused: true,
@@ -116,17 +108,12 @@ impl App {
                 return false;
             }
 
-            // if let Err(e) = self.game.draw(&mut self.canvas, &mut self.backbuffer) {
-            //     error!("Failed to draw game: {}", e);
-            // }
-
+            // Sleep if we still have time left
             if start.elapsed() < LOOP_TIME {
                 let time = LOOP_TIME.saturating_sub(start.elapsed());
                 if time != Duration::ZERO {
                     get_platform().sleep(time, self.focused);
                 }
-            } else {
-                warn!("Game loop behind schedule by: {:?}", start.elapsed() - LOOP_TIME);
             }
 
             true

src/entity/graph.rs

@@ -1,17 +1,21 @@
 use glam::Vec2;
 
-use crate::systems::components::NodeId;
+use crate::systems::movement::NodeId;
 
 use super::direction::Direction;
 
-/// Defines who can traverse a given edge.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
-pub enum EdgePermissions {
-    /// Anyone can use this edge.
-    #[default]
-    All,
-    /// Only ghosts can use this edge.
-    GhostsOnly,
+use bitflags::bitflags;
+
+bitflags! {
+    /// Defines who can traverse a given edge using flags for fast checking.
+    #[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+    pub struct TraversalFlags: u8 {
+        const PACMAN = 1 << 0;
+        const GHOST = 1 << 1;
+
+        /// Convenience flag for edges that all entities can use
+        const ALL = Self::PACMAN.bits() | Self::GHOST.bits();
+    }
 }
 
 /// Represents a directed edge from one node to another with a given weight (e.g., distance).
@@ -24,7 +28,7 @@ pub struct Edge {
     /// The cardinal direction of this edge.
     pub direction: Direction,
     /// Defines who is allowed to traverse this edge.
-    pub permissions: EdgePermissions,
+    pub traversal_flags: TraversalFlags,
 }
 
 /// Represents a node in the graph, defined by its position.
@@ -132,8 +136,8 @@ impl Graph {
             return Err("To node does not exist.");
         }
 
-        let edge_a = self.add_edge(from, to, replace, distance, direction, EdgePermissions::default());
-        let edge_b = self.add_edge(to, from, replace, distance, direction.opposite(), EdgePermissions::default());
+        let edge_a = self.add_edge(from, to, replace, distance, direction, TraversalFlags::ALL);
+        let edge_b = self.add_edge(to, from, replace, distance, direction.opposite(), TraversalFlags::ALL);
 
         if edge_a.is_err() && edge_b.is_err() {
             return Err("Failed to connect nodes in both directions.");
@@ -161,7 +165,7 @@ impl Graph {
         replace: bool,
         distance: Option<f32>,
         direction: Direction,
-        permissions: EdgePermissions,
+        traversal_flags: TraversalFlags,
     ) -> Result<(), &'static str> {
         let edge = Edge {
             target: to,
@@ -180,7 +184,7 @@ impl Graph {
                 }
             },
             direction,
-            permissions,
+            traversal_flags,
         };
 
         if from >= self.adjacency_list.len() {
@@ -219,6 +223,19 @@ impl Graph {
         self.nodes.len()
     }
 
+    /// Returns an iterator over all nodes in the graph.
+    pub fn nodes(&self) -> impl Iterator<Item = &Node> {
+        self.nodes.iter()
+    }
+
+    /// Returns an iterator over all edges in the graph.
+    pub fn edges(&self) -> impl Iterator<Item = (NodeId, Edge)> + '_ {
+        self.adjacency_list
+            .iter()
+            .enumerate()
+            .flat_map(|(node_id, intersection)| intersection.edges().map(move |edge| (node_id, 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)

src/game/mod.rs

@@ -8,21 +8,31 @@ use crate::error::{GameError, GameResult, TextureError};
 use crate::events::GameEvent;
 use crate::map::builder::Map;
 use crate::systems::blinking::Blinking;
+use crate::systems::movement::{Movable, MovementState, Position};
 use crate::systems::{
     blinking::blinking_system,
     collision::collision_system,
     components::{
         Collider, CollisionLayer, DeltaTime, DirectionalAnimated, EntityType, GlobalState, ItemBundle, ItemCollider,
-        PacmanCollider, PlayerBundle, PlayerControlled, Position, Renderable, Score, ScoreResource, Velocity,
+        PacmanCollider, PlayerBundle, PlayerControlled, RenderDirty, Renderable, Score, ScoreResource,
     },
     control::player_system,
+    debug::{debug_render_system, DebugState, DebugTextureResource},
     input::input_system,
     movement::movement_system,
-    render::{directional_render_system, render_system, BackbufferResource, MapTextureResource},
+    profiling::{profile, SystemTimings},
+    render::{directional_render_system, dirty_render_system, render_system, BackbufferResource, MapTextureResource},
 };
 use crate::texture::animated::AnimatedTexture;
 use bevy_ecs::schedule::IntoScheduleConfigs;
-use bevy_ecs::{event::EventRegistry, observer::Trigger, schedule::Schedule, system::ResMut, world::World};
+use bevy_ecs::system::NonSendMut;
+use bevy_ecs::{
+    event::EventRegistry,
+    observer::Trigger,
+    schedule::Schedule,
+    system::{Res, ResMut},
+    world::World,
+};
 use sdl2::image::LoadTexture;
 use sdl2::render::{Canvas, ScaleMode, TextureCreator};
 use sdl2::video::{Window, WindowContext};
@@ -70,6 +80,13 @@ impl Game {
             .map_err(|e| GameError::Sdl(e.to_string()))?;
         map_texture.set_scale_mode(ScaleMode::Nearest);
 
+        // Create debug texture at output resolution for crisp debug rendering
+        let output_size = canvas.output_size().unwrap();
+        let mut debug_texture = texture_creator
+            .create_texture_target(None, output_size.0, output_size.1)
+            .map_err(|e| GameError::Sdl(e.to_string()))?;
+        debug_texture.set_scale_mode(ScaleMode::Nearest);
+
         // Load atlas and create map texture
         let atlas_bytes = get_asset_bytes(Asset::Atlas)?;
         let atlas_texture = texture_creator.load_texture_bytes(&atlas_bytes).map_err(|e| {
@@ -98,7 +115,7 @@ impl Game {
         // Render map to texture
         canvas
             .with_texture_canvas(&mut map_texture, |map_canvas| {
-                MapRenderer::render_map(map_canvas, &mut atlas, &mut map_tiles);
+                MapRenderer::render_map(map_canvas, &mut atlas, &map_tiles);
             })
             .map_err(|e| GameError::Sdl(e.to_string()))?;
 
@@ -133,11 +150,15 @@ impl Game {
 
         let player = PlayerBundle {
             player: PlayerControlled,
-            position: Position::AtNode(pacman_start_node),
-            velocity: Velocity {
-                direction: Direction::Left,
-                next_direction: Some((Direction::Left, 90)),
+            position: Position {
+                node: pacman_start_node,
+                edge_progress: None,
+            },
+            movement_state: MovementState::Stopped,
+            movable: Movable {
                 speed: 1.15,
+                current_direction: Direction::Left,
+                requested_direction: Some(Direction::Left), // Start moving left immediately
             },
             sprite: Renderable {
                 sprite: SpriteAtlas::get_tile(&atlas, "pacman/full.png")
@@ -151,7 +172,7 @@ impl Game {
             },
             entity_type: EntityType::Player,
             collider: Collider {
-                size: constants::CELL_SIZE as f32 * 1.25,
+                size: constants::CELL_SIZE as f32 * 1.375,
                 layer: CollisionLayer::PACMAN,
             },
             pacman_collider: PacmanCollider,
@@ -162,38 +183,59 @@ impl Game {
         world.insert_non_send_resource(canvas);
         world.insert_non_send_resource(BackbufferResource(backbuffer));
         world.insert_non_send_resource(MapTextureResource(map_texture));
+        world.insert_non_send_resource(DebugTextureResource(debug_texture));
 
         world.insert_resource(map);
         world.insert_resource(GlobalState { exit: false });
         world.insert_resource(ScoreResource(0));
+        world.insert_resource(SystemTimings::default());
         world.insert_resource(Bindings::default());
         world.insert_resource(DeltaTime(0f32));
+        world.insert_resource(RenderDirty::default());
+        world.insert_resource(DebugState::default());
 
         world.add_observer(
-            |event: Trigger<GameEvent>, mut state: ResMut<GlobalState>, mut score: ResMut<ScoreResource>| match *event {
+            |event: Trigger<GameEvent>, mut state: ResMut<GlobalState>, _score: ResMut<ScoreResource>| match *event {
                 GameEvent::Command(command) => match command {
                     GameCommand::Exit => {
                         state.exit = true;
                     }
                     _ => {}
                 },
-                GameEvent::Collision(a, b) => {}
+                GameEvent::Collision(_a, _b) => {}
             },
         );
-
         schedule.add_systems(
             (
-                input_system,
-                player_system,
-                movement_system,
-                collision_system,
-                blinking_system,
-                directional_render_system,
-                render_system,
+                profile("input", input_system),
+                profile("player", player_system),
+                profile("movement", movement_system),
+                profile("collision", collision_system),
+                profile("blinking", blinking_system),
+                profile("directional_render", directional_render_system),
+                profile("dirty_render", dirty_render_system),
+                profile("render", render_system),
+                profile("debug_render", debug_render_system),
+                profile(
+                    "present",
+                    |mut canvas: NonSendMut<&mut Canvas<Window>>,
+                     backbuffer: NonSendMut<BackbufferResource>,
+                     debug_state: Res<DebugState>,
+                     mut dirty: ResMut<RenderDirty>| {
+                        if dirty.0 || *debug_state != DebugState::Off {
+                            // Only copy backbuffer to main canvas if debug rendering is off
+                            // (debug rendering draws directly to main canvas)
+                            if *debug_state == DebugState::Off {
+                                canvas.copy(&backbuffer.0, None, None).unwrap();
+                            }
+                            dirty.0 = false;
+                            canvas.present();
+                        }
+                    },
+                ),
             )
                 .chain(),
         );
-
         // Spawn player
         world.spawn(player);
 
@@ -207,18 +249,21 @@ impl Game {
 
         for (node_id, tile) in nodes {
             let (item_type, score, sprite, size) = match tile {
-                crate::constants::MapTile::Pellet => (EntityType::Pellet, 10, pellet_sprite, constants::CELL_SIZE as f32 * 0.2),
+                crate::constants::MapTile::Pellet => (EntityType::Pellet, 10, pellet_sprite, constants::CELL_SIZE as f32 * 0.4),
                 crate::constants::MapTile::PowerPellet => (
                     EntityType::PowerPellet,
                     50,
                     energizer_sprite,
-                    constants::CELL_SIZE as f32 * 0.9,
+                    constants::CELL_SIZE as f32 * 0.95,
                 ),
                 _ => continue,
             };
 
             let mut item = world.spawn(ItemBundle {
-                position: Position::AtNode(node_id),
+                position: Position {
+                    node: node_id,
+                    edge_progress: None,
+                },
                 sprite: Renderable {
                     sprite,
                     layer: 1,

src/map/builder.rs

@@ -1,11 +1,10 @@
 //! Map construction and building functionality.
-
 use crate::constants::{MapTile, BOARD_CELL_SIZE, CELL_SIZE};
 use crate::entity::direction::Direction;
-use crate::entity::graph::{EdgePermissions, Graph, Node};
+use crate::entity::graph::{Graph, Node, TraversalFlags};
 use crate::map::parser::MapTileParser;
 use crate::map::render::MapRenderer;
-use crate::systems::components::NodeId;
+use crate::systems::movement::NodeId;
 use crate::texture::sprite::SpriteAtlas;
 use bevy_ecs::resource::Resource;
 use glam::{IVec2, Vec2};
@@ -166,44 +165,6 @@ impl Map {
         })
     }
 
-    /// Generates Item entities for pellets and energizers from the parsed map.
-    // pub fn generate_items(&self, atlas: &SpriteAtlas) -> GameResult<Vec<Item>> {
-    //     // Pre-load sprites to avoid repeated texture lookups
-    //     let pellet_sprite = SpriteAtlas::get_tile(atlas, "maze/pellet.png")
-    //         .ok_or_else(|| MapError::InvalidConfig("Pellet texture not found".to_string()))?;
-    //     let energizer_sprite = SpriteAtlas::get_tile(atlas, "maze/energizer.png")
-    //         .ok_or_else(|| MapError::InvalidConfig("Energizer texture not found".to_string()))?;
-
-    //     // Pre-allocate with estimated capacity (typical Pac-Man maps have ~240 pellets + 4 energizers)
-    //     let mut items = Vec::with_capacity(250);
-
-    //     // Parse the raw board once
-    //     let parsed_map = MapTileParser::parse_board(RAW_BOARD)?;
-    //     let map = parsed_map.tiles;
-
-    //     // Iterate through the map and collect items more efficiently
-    //     for (x, row) in map.iter().enumerate() {
-    //         for (y, tile) in row.iter().enumerate() {
-    //             match tile {
-    //                 MapTile::Pellet | MapTile::PowerPellet => {
-    //                     let grid_pos = IVec2::new(x as i32, y as i32);
-    //                     if let Some(&node_id) = self.grid_to_node.get(&grid_pos) {
-    //                         let (item_type, sprite) = match tile {
-    //                             MapTile::Pellet => (ItemType::Pellet, Sprite::new(pellet_sprite)),
-    //                             MapTile::PowerPellet => (ItemType::Energizer, Sprite::new(energizer_sprite)),
-    //                             _ => unreachable!(), // We already filtered for these types
-    //                         };
-    //                         items.push(Item::new(node_id, item_type, sprite));
-    //                     }
-    //                 }
-    //                 _ => {}
-    //             }
-    //         }
-    //     }
-
-    //     Ok(items)
-    // }
-
     /// Renders a debug visualization with cursor-based highlighting.
     ///
     /// This function provides interactive debugging by highlighting the nearest node
@@ -304,7 +265,7 @@ impl Map {
                 false,
                 None,
                 Direction::Down,
-                EdgePermissions::GhostsOnly,
+                TraversalFlags::GHOST,
             )
             .map_err(|e| MapError::InvalidConfig(format!("Failed to create ghost-only entrance to house: {e}")))?;
 
@@ -315,7 +276,7 @@ impl Map {
                 false,
                 None,
                 Direction::Up,
-                EdgePermissions::GhostsOnly,
+                TraversalFlags::GHOST,
             )
             .map_err(|e| MapError::InvalidConfig(format!("Failed to create ghost-only exit from house: {e}")))?;
 

src/map/render.rs

@@ -19,7 +19,7 @@ impl MapRenderer {
     ///
     /// This function draws the static map texture to the screen at the correct
     /// position and scale.
-    pub fn render_map<T: RenderTarget>(canvas: &mut Canvas<T>, atlas: &mut SpriteAtlas, map_tiles: &mut [AtlasTile]) {
+    pub fn render_map<T: RenderTarget>(canvas: &mut Canvas<T>, atlas: &mut SpriteAtlas, map_tiles: &[AtlasTile]) {
         for (y, row) in TILE_MAP.iter().enumerate() {
             for (x, &tile_index) in row.iter().enumerate() {
                 let mut tile = map_tiles[tile_index];

src/systems/collision.rs

@@ -6,7 +6,8 @@ use bevy_ecs::system::{Query, Res};
 use crate::error::GameError;
 use crate::events::GameEvent;
 use crate::map::builder::Map;
-use crate::systems::components::{Collider, ItemCollider, PacmanCollider, Position};
+use crate::systems::components::{Collider, ItemCollider, PacmanCollider};
+use crate::systems::movement::Position;
 
 pub fn collision_system(
     map: Res<Map>,

src/systems/components.rs

@@ -1,10 +1,9 @@
 use bevy_ecs::{bundle::Bundle, component::Component, resource::Resource};
 use bitflags::bitflags;
-use glam::Vec2;
 
 use crate::{
-    entity::{direction::Direction, graph::Graph},
-    error::{EntityError, GameResult},
+    entity::graph::TraversalFlags,
+    systems::movement::{Movable, MovementState, Position},
     texture::{animated::AnimatedTexture, sprite::AtlasTile},
 };
 
@@ -19,7 +18,17 @@ pub enum EntityType {
     Ghost,
     Pellet,
     PowerPellet,
-    Wall,
+}
+
+impl EntityType {
+    /// Returns the traversal flags for this entity type.
+    pub fn traversal_flags(&self) -> TraversalFlags {
+        match self {
+            EntityType::Player => TraversalFlags::PACMAN,
+            EntityType::Ghost => TraversalFlags::GHOST,
+            _ => TraversalFlags::empty(), // Static entities don't traverse
+        }
+    }
 }
 
 /// A component for entities that have a sprite, with a layer for ordering.
@@ -39,103 +48,6 @@ pub struct DirectionalAnimated {
     pub stopped_textures: [Option<AnimatedTexture>; 4],
 }
 
-/// A unique identifier for a node, represented by its index in the graph's storage.
-pub type NodeId = usize;
-
-/// Represents the current position of an entity traversing the graph.
-///
-/// This enum allows for precise tracking of whether an entity is exactly at a node
-/// or moving along an edge between two nodes.
-#[derive(Component, Debug, Copy, Clone, PartialEq)]
-pub enum Position {
-    /// The traverser is located exactly at a node.
-    AtNode(NodeId),
-    /// The traverser is on an edge between two nodes.
-    BetweenNodes {
-        from: NodeId,
-        to: NodeId,
-        /// The floating-point distance traversed along the edge from the `from` node.
-        traversed: f32,
-    },
-}
-
-impl Position {
-    /// Calculates the current pixel position in the game world.
-    ///
-    /// Converts the graph position to screen coordinates, accounting for
-    /// the board offset and centering the sprite.
-    ///
-    /// # Errors
-    ///
-    /// Returns an `EntityError` if the node or edge is not found.
-    pub fn get_pixel_pos(&self, graph: &Graph) -> GameResult<Vec2> {
-        let pos = match self {
-            Position::AtNode(node_id) => {
-                let node = graph.get_node(*node_id).ok_or(EntityError::NodeNotFound(*node_id))?;
-                node.position
-            }
-            Position::BetweenNodes { from, to, traversed } => {
-                let from_node = graph.get_node(*from).ok_or(EntityError::NodeNotFound(*from))?;
-                let to_node = graph.get_node(*to).ok_or(EntityError::NodeNotFound(*to))?;
-                let edge = graph
-                    .find_edge(*from, *to)
-                    .ok_or(EntityError::EdgeNotFound { from: *from, to: *to })?;
-                from_node.position + (to_node.position - from_node.position) * (traversed / edge.distance)
-            }
-        };
-
-        Ok(Vec2::new(
-            pos.x + crate::constants::BOARD_PIXEL_OFFSET.x as f32,
-            pos.y + crate::constants::BOARD_PIXEL_OFFSET.y as f32,
-        ))
-    }
-}
-
-impl Default for Position {
-    fn default() -> Self {
-        Position::AtNode(0)
-    }
-}
-
-#[allow(dead_code)]
-impl Position {
-    /// Returns `true` if the position is exactly at a node.
-    pub fn is_at_node(&self) -> bool {
-        matches!(self, Position::AtNode(_))
-    }
-
-    /// Returns the `NodeId` of the current or most recently departed node.
-    #[allow(clippy::wrong_self_convention)]
-    pub fn from_node_id(&self) -> NodeId {
-        match self {
-            Position::AtNode(id) => *id,
-            Position::BetweenNodes { from, .. } => *from,
-        }
-    }
-
-    /// Returns the `NodeId` of the destination node, if currently on an edge.
-    #[allow(clippy::wrong_self_convention)]
-    pub fn to_node_id(&self) -> Option<NodeId> {
-        match self {
-            Position::AtNode(_) => None,
-            Position::BetweenNodes { to, .. } => Some(*to),
-        }
-    }
-
-    /// Returns `true` if the traverser is stopped at a node.
-    pub fn is_stopped(&self) -> bool {
-        matches!(self, Position::AtNode(_))
-    }
-}
-
-/// A component for entities that have a velocity, with a direction and speed.
-#[derive(Default, Component)]
-pub struct Velocity {
-    pub direction: Direction,
-    pub next_direction: Option<(Direction, u8)>,
-    pub speed: f32,
-}
-
 bitflags! {
     #[derive(Component, Default, Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
     pub struct CollisionLayer: u8 {
@@ -168,7 +80,8 @@ pub struct Score(pub u32);
 pub struct PlayerBundle {
     pub player: PlayerControlled,
     pub position: Position,
-    pub velocity: Velocity,
+    pub movement_state: MovementState,
+    pub movable: Movable,
     pub sprite: Renderable,
     pub directional_animated: DirectionalAnimated,
     pub entity_type: EntityType,
@@ -196,3 +109,6 @@ pub struct ScoreResource(pub u32);
 
 #[derive(Resource)]
 pub struct DeltaTime(pub f32);
+
+#[derive(Resource, Default)]
+pub struct RenderDirty(pub bool);

src/systems/control.rs

@@ -8,19 +8,22 @@ use bevy_ecs::{
 use crate::{
     error::GameError,
     events::{GameCommand, GameEvent},
-    systems::components::{GlobalState, PlayerControlled, Velocity},
+    systems::components::{GlobalState, PlayerControlled},
+    systems::debug::DebugState,
+    systems::movement::Movable,
 };
 
-// Handles
+// Handles player input and control
 pub fn player_system(
     mut events: EventReader<GameEvent>,
     mut state: ResMut<GlobalState>,
-    mut players: Query<&mut Velocity, With<PlayerControlled>>,
+    mut debug_state: ResMut<DebugState>,
+    mut players: Query<&mut Movable, With<PlayerControlled>>,
     mut errors: EventWriter<GameError>,
 ) {
-    // Get the player's velocity (handling to ensure there is only one player)
-    let mut velocity = match players.single_mut() {
-        Ok(velocity) => velocity,
+    // Get the player's movable component (ensuring there is only one player)
+    let mut movable = match players.single_mut() {
+        Ok(movable) => movable,
         Err(e) => {
             errors.write(GameError::InvalidState(format!("No/multiple entities queried for player system: {}", e)).into());
             return;
@@ -29,18 +32,18 @@ pub fn player_system(
 
     // Handle events
     for event in events.read() {
-        match event {
-            GameEvent::Command(command) => match command {
+        if let GameEvent::Command(command) = event {
+            match command {
                 GameCommand::MovePlayer(direction) => {
-                    velocity.next_direction = Some((*direction, 90));
+                    movable.requested_direction = Some(*direction);
                 }
                 GameCommand::Exit => {
                     state.exit = true;
                 }
+                GameCommand::ToggleDebug => {
+                    *debug_state = debug_state.next();
+                }
                 _ => {}
-            },
-            GameEvent::Collision(a, b) => {
-                tracing::info!("Collision between {:?} and {:?}", a, b);
             }
         }
     }

src/systems/debug.rs

@@ -0,0 +1,189 @@
+//! Debug rendering system
+use crate::constants::BOARD_PIXEL_OFFSET;
+use crate::map::builder::Map;
+use crate::systems::components::Collider;
+use crate::systems::movement::Position;
+use crate::systems::profiling::SystemTimings;
+use crate::systems::render::BackbufferResource;
+use bevy_ecs::prelude::*;
+use sdl2::pixels::Color;
+use sdl2::rect::Rect;
+use sdl2::render::{Canvas, Texture, TextureCreator};
+use sdl2::video::{Window, WindowContext};
+
+#[derive(Resource, Default, Debug, Copy, Clone, PartialEq)]
+pub enum DebugState {
+    #[default]
+    Off,
+    Graph,
+    Collision,
+}
+
+impl DebugState {
+    pub fn next(&self) -> Self {
+        match self {
+            DebugState::Off => DebugState::Graph,
+            DebugState::Graph => DebugState::Collision,
+            DebugState::Collision => DebugState::Off,
+        }
+    }
+}
+
+/// Resource to hold the debug texture for persistent rendering
+pub struct DebugTextureResource(pub Texture<'static>);
+
+/// Transforms a position from logical canvas coordinates to output canvas coordinates
+fn transform_position(pos: (f32, f32), output_size: (u32, u32), logical_size: (u32, u32)) -> (i32, i32) {
+    let scale_x = output_size.0 as f32 / logical_size.0 as f32;
+    let scale_y = output_size.1 as f32 / logical_size.1 as f32;
+    let scale = scale_x.min(scale_y); // Use the smaller scale to maintain aspect ratio
+
+    let x = (pos.0 * scale) as i32;
+    let y = (pos.1 * scale) as i32;
+    (x, y)
+}
+
+/// Transforms a position from logical canvas coordinates to output canvas coordinates (with board offset)
+fn transform_position_with_offset(pos: (f32, f32), output_size: (u32, u32), logical_size: (u32, u32)) -> (i32, i32) {
+    let scale_x = output_size.0 as f32 / logical_size.0 as f32;
+    let scale_y = output_size.1 as f32 / logical_size.1 as f32;
+    let scale = scale_x.min(scale_y); // Use the smaller scale to maintain aspect ratio
+
+    let x = ((pos.0 + BOARD_PIXEL_OFFSET.x as f32) * scale) as i32;
+    let y = ((pos.1 + BOARD_PIXEL_OFFSET.y as f32) * scale) as i32;
+    (x, y)
+}
+
+/// Transforms a size from logical canvas coordinates to output canvas coordinates
+fn transform_size(size: f32, output_size: (u32, u32), logical_size: (u32, u32)) -> u32 {
+    let scale_x = output_size.0 as f32 / logical_size.0 as f32;
+    let scale_y = output_size.1 as f32 / logical_size.1 as f32;
+    let scale = scale_x.min(scale_y); // Use the smaller scale to maintain aspect ratio
+
+    (size * scale) as u32
+}
+
+/// Renders timing information in the top-left corner of the screen
+fn render_timing_display(
+    canvas: &mut Canvas<Window>,
+    texture_creator: &mut TextureCreator<WindowContext>,
+    timings: &SystemTimings,
+) {
+    // Get TTF context
+    let ttf_context = sdl2::ttf::init().unwrap();
+
+    // Load font
+    let font = ttf_context.load_font("assets/site/TerminalVector.ttf", 12).unwrap();
+
+    // Format timing information using the formatting module
+    let timing_text = timings.format_timing_display();
+
+    // Split text by newlines and render each line separately
+    let lines: Vec<&str> = timing_text.lines().collect();
+    let line_height = 14; // Approximate line height for 12pt font
+    let padding = 10;
+
+    for (i, line) in lines.iter().enumerate() {
+        if line.is_empty() {
+            continue;
+        }
+
+        // Render each line
+        let surface = font.render(line).blended(Color::RGBA(255, 255, 255, 200)).unwrap();
+        let texture = texture_creator.create_texture_from_surface(&surface).unwrap();
+
+        // Position each line below the previous one
+        let y_pos = padding + (i * line_height) as i32;
+        let dest = Rect::new(padding, y_pos, texture.query().width, texture.query().height);
+        canvas.copy(&texture, None, dest).unwrap();
+    }
+}
+
+pub fn debug_render_system(
+    mut canvas: NonSendMut<&mut Canvas<Window>>,
+    backbuffer: NonSendMut<BackbufferResource>,
+    mut debug_texture: NonSendMut<DebugTextureResource>,
+    debug_state: Res<DebugState>,
+    timings: Res<SystemTimings>,
+    map: Res<Map>,
+    colliders: Query<(&Collider, &Position)>,
+) {
+    if *debug_state == DebugState::Off {
+        return;
+    }
+
+    // Get canvas sizes for coordinate transformation
+    let output_size = canvas.output_size().unwrap();
+    let logical_size = canvas.logical_size();
+
+    // Copy the current backbuffer to the debug texture
+    canvas
+        .with_texture_canvas(&mut debug_texture.0, |debug_canvas| {
+            // Clear the debug canvas
+            debug_canvas.set_draw_color(Color::BLACK);
+            debug_canvas.clear();
+
+            // Copy the backbuffer to the debug canvas
+            debug_canvas.copy(&backbuffer.0, None, None).unwrap();
+        })
+        .unwrap();
+
+    // Get texture creator before entering the closure to avoid borrowing conflicts
+    let mut texture_creator = canvas.texture_creator();
+
+    // Draw debug info on the high-resolution debug texture
+    canvas
+        .with_texture_canvas(&mut debug_texture.0, |debug_canvas| {
+            match *debug_state {
+                DebugState::Graph => {
+                    debug_canvas.set_draw_color(Color::RED);
+                    for (start_node, end_node) in map.graph.edges() {
+                        let start_node = map.graph.get_node(start_node).unwrap().position;
+                        let end_node = map.graph.get_node(end_node.target).unwrap().position;
+
+                        // Transform positions using common method
+                        let (start_x, start_y) =
+                            transform_position_with_offset((start_node.x, start_node.y), output_size, logical_size);
+                        let (end_x, end_y) = transform_position_with_offset((end_node.x, end_node.y), output_size, logical_size);
+
+                        debug_canvas.draw_line((start_x, start_y), (end_x, end_y)).unwrap();
+                    }
+
+                    debug_canvas.set_draw_color(Color::BLUE);
+                    for node in map.graph.nodes() {
+                        let pos = node.position;
+
+                        // Transform position using common method
+                        let (x, y) = transform_position_with_offset((pos.x, pos.y), output_size, logical_size);
+                        let size = transform_size(4.0, output_size, logical_size);
+
+                        debug_canvas
+                            .fill_rect(Rect::new(x - (size as i32 / 2), y - (size as i32 / 2), size, size))
+                            .unwrap();
+                    }
+                }
+                DebugState::Collision => {
+                    debug_canvas.set_draw_color(Color::GREEN);
+                    for (collider, position) in colliders.iter() {
+                        let pos = position.get_pixel_pos(&map.graph).unwrap();
+
+                        // Transform position and size using common methods
+                        let (x, y) = transform_position((pos.x, pos.y), output_size, logical_size);
+                        let size = transform_size(collider.size, output_size, logical_size);
+
+                        // Center the collision box on the entity
+                        let rect = Rect::new(x - (size as i32 / 2), y - (size as i32 / 2), size, size);
+                        debug_canvas.draw_rect(rect).unwrap();
+                    }
+                }
+                _ => {}
+            }
+
+            // Render timing information in the top-left corner
+            render_timing_display(debug_canvas, &mut texture_creator, &timings);
+        })
+        .unwrap();
+
+    // Draw the debug texture directly onto the main canvas at full resolution
+    canvas.copy(&debug_texture.0, None, None).unwrap();
+}

src/systems/formatting.rs

@@ -0,0 +1,151 @@
+use num_width::NumberWidth;
+use std::time::Duration;
+
+/// Formats timing data into a vector of strings with proper alignment
+pub fn format_timing_display(timing_data: Vec<(String, Duration, Duration)>) -> String {
+    if timing_data.is_empty() {
+        return String::new();
+    }
+
+    // Helper to split a duration into a integer, decimal, and unit
+    fn get_value(duration: &Duration) -> (u64, u32, &'static str) {
+        let (int, decimal, unit) = match duration {
+            // if greater than 1 second, return as seconds
+            n if n >= &Duration::from_secs(1) => {
+                let secs = n.as_secs();
+                let decimal = n.as_millis() as u64 % 1000;
+                (secs, decimal as u32, "s")
+            }
+            // if greater than 1 millisecond, return as milliseconds
+            n if n >= &Duration::from_millis(1) => {
+                let ms = n.as_millis() as u64;
+                let decimal = n.as_micros() as u64 % 1000;
+                (ms, decimal as u32, "ms")
+            }
+            // if greater than 1 microsecond, return as microseconds
+            n if n >= &Duration::from_micros(1) => {
+                let us = n.as_micros() as u64;
+                let decimal = n.as_nanos() as u64 % 1000;
+                (us, decimal as u32, "µs")
+            }
+            // otherwise, return as nanoseconds
+            n => {
+                let ns = n.as_nanos() as u64;
+                (ns, 0, "ns")
+            }
+        };
+
+        (int, decimal, unit)
+    }
+
+    struct Entry {
+        name: String,
+        avg_int: u64,
+        avg_decimal: u32,
+        avg_unit: &'static str,
+        std_int: u64,
+        std_decimal: u32,
+        std_unit: &'static str,
+    }
+
+    let entries = timing_data
+        .iter()
+        .map(|(name, avg, std_dev)| {
+            let (avg_int, avg_decimal, avg_unit) = get_value(&avg);
+            let (std_int, std_decimal, std_unit) = get_value(&std_dev);
+
+            Entry {
+                name: name.clone(),
+                avg_int,
+                avg_decimal,
+                avg_unit,
+                std_int,
+                std_decimal,
+                std_unit,
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let max_name_width = entries.iter().map(|e| e.name.len() as usize).max().unwrap_or(0);
+    let max_avg_int_width = entries.iter().map(|e| e.avg_int.width() as usize).max().unwrap_or(0);
+    let max_avg_decimal_width = entries
+        .iter()
+        .map(|e| e.avg_decimal.width() as usize)
+        .max()
+        .unwrap_or(0)
+        .max(3);
+    let max_std_int_width = entries.iter().map(|e| e.std_int.width() as usize).max().unwrap_or(0);
+    let max_std_decimal_width = entries
+        .iter()
+        .map(|e| e.std_decimal.width() as usize)
+        .max()
+        .unwrap_or(0)
+        .max(3);
+
+    let mut output_lines = Vec::new();
+
+    // Format each line using the calculated max widths for alignment
+    for Entry {
+        name,
+        avg_int,
+        avg_decimal,
+        avg_unit,
+        std_int,
+        std_decimal,
+        std_unit,
+    } in entries.iter()
+    {
+        // Add exactly 4 spaces of padding before each number
+        let avg_padding = " ".repeat(4);
+        let std_padding = " ".repeat(4);
+
+        output_lines.push(format!(
+            "{name:max_name_width$} : {avg_int:max_avg_int_width$}.{avg_decimal:<max_avg_decimal_width$}{avg_unit} ± {std_int:max_std_int_width$}.{std_decimal:<max_std_decimal_width$}{std_unit}"
+        ));
+    }
+
+    output_lines.join("\n")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use pretty_assertions::assert_eq;
+    use std::time::Duration;
+
+    #[test]
+    fn test_format_timing_display() {
+        let timing_data = vec![
+            ("total".to_string(), Duration::from_micros(1234), Duration::from_micros(570)),
+            ("input".to_string(), Duration::from_micros(120), Duration::from_micros(45)),
+            ("player".to_string(), Duration::from_micros(456), Duration::from_micros(123)),
+            ("movement".to_string(), Duration::from_micros(789), Duration::from_micros(234)),
+            ("render".to_string(), Duration::from_micros(12), Duration::from_micros(3)),
+            ("debug".to_string(), Duration::from_nanos(460), Duration::from_nanos(557)),
+        ];
+
+        let result = format_timing_display(timing_data);
+        let lines: Vec<&str> = result.lines().collect();
+
+        // Verify we have the expected number of lines
+        assert_eq!(lines.len(), 6);
+
+        let expected = r#"
+total    :   1.234ms ± 570.0  µs
+input    : 120.0  µs ±  45.0  µs
+player   : 456.0  µs ± 123.0  µs
+movement : 789.0  µs ± 234.0  µs
+render   :  12.0  µs ±   3.0  µs
+debug    : 460.0  ns ± 557.0  ns
+"#
+        .trim();
+
+        for (line, expected_line) in lines.iter().zip(expected.lines()) {
+            assert_eq!(*line, expected_line);
+        }
+
+        // Print the result for manual inspection
+        println!("Formatted output:");
+        println!("{}", result);
+    }
+}

src/systems/input.rs

@@ -48,7 +48,6 @@ pub fn input_system(bindings: Res<Bindings>, mut writer: EventWriter<GameEvent>,
             Event::KeyDown { keycode: Some(key), .. } => {
                 let command = bindings.key_bindings.get(&key).copied();
                 if let Some(command) = command {
-                    tracing::info!("triggering command: {:?}", command);
                     writer.write(GameEvent::Command(command));
                 }
             }

src/systems/mod.rs

@@ -7,6 +7,9 @@ pub mod blinking;
 pub mod collision;
 pub mod components;
 pub mod control;
+pub mod debug;
+pub mod formatting;
 pub mod input;
 pub mod movement;
+pub mod profiling;
 pub mod render;

src/systems/movement.rs

@@ -1,131 +1,270 @@
-use crate::entity::graph::{Edge, EdgePermissions};
-use crate::error::{EntityError, GameError};
+use crate::entity::graph::Graph;
+use crate::entity::{direction::Direction, graph::Edge};
+use crate::error::{EntityError, GameError, GameResult};
 use crate::map::builder::Map;
-use crate::systems::components::{DeltaTime, EntityType, Position, Velocity};
+use crate::systems::components::{DeltaTime, EntityType};
+use bevy_ecs::component::Component;
 use bevy_ecs::event::EventWriter;
 use bevy_ecs::system::{Query, Res};
+use glam::Vec2;
+
+/// A unique identifier for a node, represented by its index in the graph's storage.
+pub type NodeId = usize;
+
+/// Progress along an edge between two nodes.
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub struct EdgeProgress {
+    pub target_node: NodeId,
+    /// Progress from 0.0 (at source node) to 1.0 (at target node)
+    pub progress: f32,
+}
+
+/// Pure spatial position component - works for both static and dynamic entities.
+#[derive(Component, Debug, Copy, Clone, PartialEq)]
+pub struct Position {
+    /// The current/primary node this entity is at or traveling from
+    pub node: NodeId,
+    /// If Some, entity is traveling between nodes. If None, entity is stationary at node.
+    pub edge_progress: Option<EdgeProgress>,
+}
+
+/// Explicit movement state - only for entities that can move.
+#[derive(Component, Debug, Clone, Copy, PartialEq)]
+pub enum MovementState {
+    Stopped,
+    Moving { direction: Direction },
+}
+
+/// Movement capability and parameters - only for entities that can move.
+#[derive(Component, Debug, Clone, Copy)]
+pub struct Movable {
+    pub speed: f32,
+    pub current_direction: Direction,
+    pub requested_direction: Option<Direction>,
+}
+
+impl Position {
+    /// Calculates the current pixel position in the game world.
+    ///
+    /// Converts the graph position to screen coordinates, accounting for
+    /// the board offset and centering the sprite.
+    ///
+    /// # Errors
+    ///
+    /// Returns an `EntityError` if the node or edge is not found.
+    pub fn get_pixel_pos(&self, graph: &Graph) -> GameResult<Vec2> {
+        let pos = match &self.edge_progress {
+            None => {
+                // Entity is stationary at a node
+                let node = graph.get_node(self.node).ok_or(EntityError::NodeNotFound(self.node))?;
+                node.position
+            }
+            Some(edge_progress) => {
+                // Entity is traveling between nodes
+                let from_node = graph.get_node(self.node).ok_or(EntityError::NodeNotFound(self.node))?;
+                let to_node = graph
+                    .get_node(edge_progress.target_node)
+                    .ok_or(EntityError::NodeNotFound(edge_progress.target_node))?;
+
+                // For zero-distance edges (tunnels), progress >= 1.0 means we're at the target
+                if edge_progress.progress >= 1.0 {
+                    to_node.position
+                } else {
+                    // Interpolate position based on progress
+                    from_node.position + (to_node.position - from_node.position) * edge_progress.progress
+                }
+            }
+        };
+
+        Ok(Vec2::new(
+            pos.x + crate::constants::BOARD_PIXEL_OFFSET.x as f32,
+            pos.y + crate::constants::BOARD_PIXEL_OFFSET.y as f32,
+        ))
+    }
+}
+
+impl Default for Position {
+    fn default() -> Self {
+        Position {
+            node: 0,
+            edge_progress: None,
+        }
+    }
+}
+
+#[allow(dead_code)]
+impl Position {
+    /// Returns `true` if the position is exactly at a node (not traveling).
+    pub fn is_at_node(&self) -> bool {
+        self.edge_progress.is_none()
+    }
+
+    /// Returns the `NodeId` of the current node (source of travel if moving).
+    pub fn current_node(&self) -> NodeId {
+        self.node
+    }
+
+    /// Returns the `NodeId` of the destination node, if currently traveling.
+    pub fn target_node(&self) -> Option<NodeId> {
+        self.edge_progress.as_ref().map(|ep| ep.target_node)
+    }
+
+    /// Returns `true` if the entity is traveling between nodes.
+    pub fn is_moving(&self) -> bool {
+        self.edge_progress.is_some()
+    }
+}
 
 fn can_traverse(entity_type: EntityType, edge: Edge) -> bool {
-    match entity_type {
-        EntityType::Player => matches!(edge.permissions, EdgePermissions::All),
-        EntityType::Ghost => matches!(edge.permissions, EdgePermissions::All | EdgePermissions::GhostsOnly),
-        _ => matches!(edge.permissions, EdgePermissions::All),
-    }
+    let entity_flags = entity_type.traversal_flags();
+    edge.traversal_flags.contains(entity_flags)
 }
 
 pub fn movement_system(
     map: Res<Map>,
     delta_time: Res<DeltaTime>,
-    mut entities: Query<(&mut Velocity, &mut Position, &EntityType)>,
+    mut entities: Query<(&mut MovementState, &mut Movable, &mut Position, &EntityType)>,
     mut errors: EventWriter<GameError>,
 ) {
-    for (mut velocity, mut position, entity_type) in entities.iter_mut() {
-        let distance = velocity.speed * 60.0 * delta_time.0;
+    for (mut movement_state, mut movable, mut position, entity_type) in entities.iter_mut() {
+        let distance = movable.speed * 60.0 * delta_time.0;
 
-        // Decrement the remaining frames for the next direction
-        if let Some((direction, remaining)) = velocity.next_direction {
-            if remaining > 0 {
-                velocity.next_direction = Some((direction, remaining - 1));
-            } else {
-                velocity.next_direction = None;
-            }
-        }
-
-        match *position {
-            Position::AtNode(node_id) => {
-                // We're not moving, but a buffered direction is available.
-                if let Some((next_direction, _)) = velocity.next_direction {
-                    if let Some(edge) = map.graph.find_edge_in_direction(node_id, next_direction) {
+        match *movement_state {
+            MovementState::Stopped => {
+                // Check if we have a requested direction to start moving
+                if let Some(requested_direction) = movable.requested_direction {
+                    if let Some(edge) = map.graph.find_edge_in_direction(position.node, requested_direction) {
                         if can_traverse(*entity_type, edge) {
-                            // Start moving in that direction
-                            *position = Position::BetweenNodes {
-                                from: node_id,
-                                to: edge.target,
-                                traversed: distance,
+                            // Start moving in the requested direction
+                            let progress = if edge.distance > 0.0 {
+                                distance / edge.distance
+                            } else {
+                                // Zero-distance edge (tunnels) - immediately teleport
+                                tracing::debug!("Entity entering tunnel from node {} to node {}", position.node, edge.target);
+                                1.0
+                            };
+
+                            position.edge_progress = Some(EdgeProgress {
+                                target_node: edge.target,
+                                progress,
+                            });
+                            movable.current_direction = requested_direction;
+                            movable.requested_direction = None;
+                            *movement_state = MovementState::Moving {
+                                direction: requested_direction,
                             };
-                            velocity.direction = next_direction;
-                            velocity.next_direction = None;
                         }
                     } else {
                         errors.write(
                             EntityError::InvalidMovement(format!(
                                 "No edge found in direction {:?} from node {}",
-                                next_direction, node_id
+                                requested_direction, position.node
                             ))
                             .into(),
                         );
                     }
                 }
             }
-            Position::BetweenNodes { from, to, traversed } => {
-                // There is no point in any of the next logic if we don't travel at all
-                if distance <= 0.0 {
-                    return;
-                }
+            MovementState::Moving { direction } => {
+                // Continue moving or handle node transitions
+                let current_node = position.node;
+                if let Some(edge_progress) = &mut position.edge_progress {
+                    // Extract target node before mutable operations
+                    let target_node = edge_progress.target_node;
 
-                let edge = map
-                    .graph
-                    .find_edge(from, to)
-                    .ok_or_else(|| {
+                    // Get the current edge for distance calculation
+                    let edge = map.graph.find_edge(current_node, target_node);
+
+                    if let Some(edge) = edge {
+                        // Update progress along the edge
+                        if edge.distance > 0.0 {
+                            edge_progress.progress += distance / edge.distance;
+                        } else {
+                            // Zero-distance edge (tunnels) - immediately complete
+                            edge_progress.progress = 1.0;
+                        }
+
+                        if edge_progress.progress >= 1.0 {
+                            // Reached the target node
+                            let overflow = if edge.distance > 0.0 {
+                                (edge_progress.progress - 1.0) * edge.distance
+                            } else {
+                                // Zero-distance edge - use remaining distance for overflow
+                                distance
+                            };
+                            position.node = target_node;
+                            position.edge_progress = None;
+
+                            let mut continued_moving = false;
+
+                            // Try to use requested direction first
+                            if let Some(requested_direction) = movable.requested_direction {
+                                if let Some(next_edge) = map.graph.find_edge_in_direction(position.node, requested_direction) {
+                                    if can_traverse(*entity_type, next_edge) {
+                                        let next_progress = if next_edge.distance > 0.0 {
+                                            overflow / next_edge.distance
+                                        } else {
+                                            // Zero-distance edge - immediately complete
+                                            1.0
+                                        };
+
+                                        position.edge_progress = Some(EdgeProgress {
+                                            target_node: next_edge.target,
+                                            progress: next_progress,
+                                        });
+                                        movable.current_direction = requested_direction;
+                                        movable.requested_direction = None;
+                                        *movement_state = MovementState::Moving {
+                                            direction: requested_direction,
+                                        };
+                                        continued_moving = true;
+                                    }
+                                }
+                            }
+
+                            // If no requested direction or it failed, try to continue in current direction
+                            if !continued_moving {
+                                if let Some(next_edge) = map.graph.find_edge_in_direction(position.node, direction) {
+                                    if can_traverse(*entity_type, next_edge) {
+                                        let next_progress = if next_edge.distance > 0.0 {
+                                            overflow / next_edge.distance
+                                        } else {
+                                            // Zero-distance edge - immediately complete
+                                            1.0
+                                        };
+
+                                        position.edge_progress = Some(EdgeProgress {
+                                            target_node: next_edge.target,
+                                            progress: next_progress,
+                                        });
+                                        // Keep current direction and movement state
+                                        continued_moving = true;
+                                    }
+                                }
+                            }
+
+                            // If we couldn't continue moving, stop
+                            if !continued_moving {
+                                *movement_state = MovementState::Stopped;
+                                movable.requested_direction = None;
+                            }
+                        }
+                    } else {
+                        // Edge not found - this is an inconsistent state
                         errors.write(
                             EntityError::InvalidMovement(format!(
-                                "Inconsistent state: Traverser is on a non-existent edge from {} to {}.",
-                                from, to
+                                "Inconsistent state: Moving on non-existent edge from {} to {}",
+                                current_node, target_node
                             ))
                             .into(),
                         );
-                        return;
-                    })
-                    .unwrap();
-
-                let new_traversed = traversed + distance;
-
-                if new_traversed < edge.distance {
-                    // Still on the same edge, just update the distance.
-                    *position = Position::BetweenNodes {
-                        from,
-                        to,
-                        traversed: new_traversed,
-                    };
+                        *movement_state = MovementState::Stopped;
+                        position.edge_progress = None;
+                    }
                 } else {
-                    let overflow = new_traversed - edge.distance;
-                    let mut moved = false;
-
-                    // If we buffered a direction, try to find an edge in that direction
-                    if let Some((next_dir, _)) = velocity.next_direction {
-                        if let Some(edge) = map.graph.find_edge_in_direction(to, next_dir) {
-                            if can_traverse(*entity_type, edge) {
-                                *position = Position::BetweenNodes {
-                                    from: to,
-                                    to: edge.target,
-                                    traversed: overflow,
-                                };
-
-                                velocity.direction = next_dir; // Remember our new direction
-                                velocity.next_direction = None; // Consume the buffered direction
-                                moved = true;
-                            }
-                        }
-                    }
-
-                    // If we didn't move, try to continue in the current direction
-                    if !moved {
-                        if let Some(edge) = map.graph.find_edge_in_direction(to, velocity.direction) {
-                            if can_traverse(*entity_type, edge) {
-                                *position = Position::BetweenNodes {
-                                    from: to,
-                                    to: edge.target,
-                                    traversed: overflow,
-                                };
-                            } else {
-                                *position = Position::AtNode(to);
-                                velocity.next_direction = None;
-                            }
-                        } else {
-                            *position = Position::AtNode(to);
-                            velocity.next_direction = None;
-                        }
-                    }
+                    // Movement state says moving but no edge progress - this shouldn't happen
+                    errors.write(EntityError::InvalidMovement("Entity in Moving state but no edge progress".to_string()).into());
+                    *movement_state = MovementState::Stopped;
                 }
             }
         }

src/systems/profiling.rs

@@ -0,0 +1,131 @@
+use bevy_ecs::prelude::Resource;
+use bevy_ecs::system::{IntoSystem, System};
+use micromap::Map;
+use parking_lot::Mutex;
+use std::collections::VecDeque;
+use std::time::Duration;
+use thousands::Separable;
+
+const TIMING_WINDOW_SIZE: usize = 30;
+
+#[derive(Resource, Default, Debug)]
+pub struct SystemTimings {
+    pub timings: Mutex<Map<&'static str, VecDeque<Duration>, 15>>,
+}
+
+impl SystemTimings {
+    pub fn add_timing(&self, name: &'static str, duration: Duration) {
+        let mut timings = self.timings.lock();
+        let queue = timings.entry(name).or_insert_with(VecDeque::new);
+
+        queue.push_back(duration);
+        if queue.len() > TIMING_WINDOW_SIZE {
+            queue.pop_front();
+        }
+    }
+
+    pub fn get_stats(&self) -> Map<&'static str, (Duration, Duration), 10> {
+        let timings = self.timings.lock();
+        let mut stats = Map::new();
+
+        for (name, queue) in timings.iter() {
+            if queue.is_empty() {
+                continue;
+            }
+
+            let durations: Vec<f64> = queue.iter().map(|d| d.as_secs_f64() * 1000.0).collect();
+            let count = durations.len() as f64;
+
+            let sum: f64 = durations.iter().sum();
+            let mean = sum / count;
+
+            let variance = durations.iter().map(|x| (x - mean).powi(2)).sum::<f64>() / count;
+            let std_dev = variance.sqrt();
+
+            stats.insert(
+                *name,
+                (
+                    Duration::from_secs_f64(mean / 1000.0),
+                    Duration::from_secs_f64(std_dev / 1000.0),
+                ),
+            );
+        }
+
+        stats
+    }
+
+    pub fn get_total_stats(&self) -> (Duration, Duration) {
+        let timings = self.timings.lock();
+        let mut all_durations = Vec::new();
+
+        for queue in timings.values() {
+            all_durations.extend(queue.iter().map(|d| d.as_secs_f64() * 1000.0));
+        }
+
+        if all_durations.is_empty() {
+            return (Duration::ZERO, Duration::ZERO);
+        }
+
+        let count = all_durations.len() as f64;
+        let sum: f64 = all_durations.iter().sum();
+        let mean = sum / count;
+
+        let variance = all_durations.iter().map(|x| (x - mean).powi(2)).sum::<f64>() / count;
+        let std_dev = variance.sqrt();
+
+        (
+            Duration::from_secs_f64(mean / 1000.0),
+            Duration::from_secs_f64(std_dev / 1000.0),
+        )
+    }
+
+    pub fn format_timing_display(&self) -> String {
+        let stats = self.get_stats();
+        let (total_avg, total_std) = self.get_total_stats();
+
+        let effective_fps = match 1.0 / total_avg.as_secs_f64() {
+            f if f > 100.0 => (f as u32).separate_with_commas(),
+            f if f < 10.0 => format!("{:.1} FPS", f),
+            f => format!("{:.0} FPS", f),
+        };
+
+        // Collect timing data for formatting
+        let mut timing_data = Vec::new();
+
+        // Add total stats
+        timing_data.push((effective_fps, total_avg, total_std));
+
+        // Add top 5 most expensive systems
+        let mut sorted_stats: Vec<_> = stats.iter().collect();
+        sorted_stats.sort_by(|a, b| b.1 .0.cmp(&a.1 .0));
+
+        for (name, (avg, std_dev)) in sorted_stats.iter().take(5) {
+            timing_data.push((name.to_string(), *avg, *std_dev));
+        }
+
+        // Use the formatting module to format the data
+        crate::systems::formatting::format_timing_display(timing_data)
+    }
+}
+
+pub fn profile<S, M>(name: &'static str, system: S) -> impl FnMut(&mut bevy_ecs::world::World)
+where
+    S: IntoSystem<(), (), M> + 'static,
+{
+    let mut system: S::System = IntoSystem::into_system(system);
+    let mut is_initialized = false;
+    move |world: &mut bevy_ecs::world::World| {
+        if !is_initialized {
+            system.initialize(world);
+            is_initialized = true;
+        }
+
+        let start = std::time::Instant::now();
+        system.run((), world);
+        let duration = start.elapsed();
+
+        if let Some(timings) = world.get_resource::<SystemTimings>() {
+            timings.add_timing(name, duration);
+        }
+    }
+}

src/systems/render.rs

@@ -1,34 +1,51 @@
 use crate::error::{GameError, TextureError};
 use crate::map::builder::Map;
-use crate::systems::components::{DeltaTime, DirectionalAnimated, Position, Renderable, Velocity};
+use crate::systems::components::{DeltaTime, DirectionalAnimated, RenderDirty, Renderable};
+use crate::systems::movement::{Movable, MovementState, Position};
 use crate::texture::sprite::SpriteAtlas;
 use bevy_ecs::entity::Entity;
 use bevy_ecs::event::EventWriter;
-use bevy_ecs::system::{NonSendMut, Query, Res};
+use bevy_ecs::prelude::{Changed, Or, RemovedComponents};
+use bevy_ecs::system::{NonSendMut, Query, Res, ResMut};
 use sdl2::render::{Canvas, Texture};
 use sdl2::video::Window;
 
+pub fn dirty_render_system(
+    mut dirty: ResMut<RenderDirty>,
+    changed_renderables: Query<(), Or<(Changed<Renderable>, Changed<Position>)>>,
+    removed_renderables: RemovedComponents<Renderable>,
+) {
+    if !changed_renderables.is_empty() || !removed_renderables.is_empty() {
+        dirty.0 = true;
+    }
+}
+
 /// Updates the directional animated texture of an entity.
 ///
 /// This runs before the render system so it can update the sprite based on the current direction of travel, as well as whether the entity is moving.
 pub fn directional_render_system(
     dt: Res<DeltaTime>,
-    mut renderables: Query<(&Velocity, &mut DirectionalAnimated, &mut Renderable, &Position)>,
+    mut renderables: Query<(&MovementState, &Movable, &mut DirectionalAnimated, &mut Renderable)>,
     mut errors: EventWriter<GameError>,
 ) {
-    for (velocity, mut texture, mut renderable, position) in renderables.iter_mut() {
-        let stopped = matches!(position, Position::AtNode(_));
+    for (movement_state, movable, mut texture, mut renderable) in renderables.iter_mut() {
+        let stopped = matches!(movement_state, MovementState::Stopped);
+        let current_direction = movable.current_direction;
+
         let texture = if stopped {
-            texture.stopped_textures[velocity.direction.as_usize()].as_mut()
+            texture.stopped_textures[current_direction.as_usize()].as_mut()
         } else {
-            texture.textures[velocity.direction.as_usize()].as_mut()
+            texture.textures[current_direction.as_usize()].as_mut()
         };
 
         if let Some(texture) = texture {
             if !stopped {
                 texture.tick(dt.0);
             }
-            renderable.sprite = *texture.current_tile();
+            let new_tile = *texture.current_tile();
+            if renderable.sprite != new_tile {
+                renderable.sprite = new_tile;
+            }
         } else {
             errors.write(TextureError::RenderFailed(format!("Entity has no texture")).into());
             continue;
@@ -48,13 +65,13 @@ pub fn render_system(
     mut backbuffer: NonSendMut<BackbufferResource>,
     mut atlas: NonSendMut<SpriteAtlas>,
     map: Res<Map>,
-    renderables: Query<(Entity, &mut Renderable, &Position)>,
+    dirty: Res<RenderDirty>,
+    renderables: Query<(Entity, &Renderable, &Position)>,
     mut errors: EventWriter<GameError>,
 ) {
-    // Clear the main canvas first
-    canvas.set_draw_color(sdl2::pixels::Color::BLACK);
-    canvas.clear();
-
+    if !dirty.0 {
+        return;
+    }
     // Render to backbuffer
     canvas
         .with_texture_canvas(&mut backbuffer.0, |backbuffer_canvas| {
@@ -63,17 +80,16 @@ pub fn render_system(
             backbuffer_canvas.clear();
 
             // Copy the pre-rendered map texture to the backbuffer
-            backbuffer_canvas
-                .copy(&map_texture.0, None, None)
-                .err()
-                .map(|e| errors.write(TextureError::RenderFailed(e.to_string()).into()));
+            if let Err(e) = backbuffer_canvas.copy(&map_texture.0, None, None) {
+                errors.write(TextureError::RenderFailed(e.to_string()).into());
+            }
 
             // Render all entities to the backbuffer
-            for (_, mut renderable, position) in renderables
-            // .iter_mut()
-            // .sort_by_key::<&mut Renderable, _, _>(|(renderable, renderable, renderable)| renderable.layer)
-            // .collect()
-            {
+            for (_, renderable, position) in renderables.iter() {
+                if !renderable.visible {
+                    continue;
+                }
+
                 let pos = position.get_pixel_pos(&map.graph);
                 match pos {
                     Ok(pos) => {
@@ -96,12 +112,4 @@ pub fn render_system(
         })
         .err()
         .map(|e| errors.write(TextureError::RenderFailed(e.to_string()).into()));
-
-    // Copy backbuffer to main canvas and present
-    canvas
-        .copy(&backbuffer.0, None, None)
-        .err()
-        .map(|e| errors.write(TextureError::RenderFailed(e.to_string()).into()));
-
-    canvas.present();
 }

src/texture/sprite.rs

@@ -21,7 +21,7 @@ pub struct MapperFrame {
     pub height: u16,
 }
 
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, PartialEq)]
 pub struct AtlasTile {
     pub pos: U16Vec2,
     pub size: U16Vec2,
@@ -30,7 +30,7 @@ pub struct AtlasTile {
 
 impl AtlasTile {
     pub fn render<C: RenderTarget>(
-        &mut self,
+        &self,
         canvas: &mut Canvas<C>,
         atlas: &mut SpriteAtlas,
         dest: Rect,
@@ -41,7 +41,7 @@ impl AtlasTile {
     }
 
     pub fn render_with_color<C: RenderTarget>(
-        &mut self,
+        &self,
         canvas: &mut Canvas<C>,
         atlas: &mut SpriteAtlas,
         dest: Rect,

src/texture/text.rs

@@ -103,9 +103,9 @@ impl TextTexture {
         &self.char_map
     }
 
-    pub fn get_tile(&mut self, c: char, atlas: &mut SpriteAtlas) -> Result<Option<&mut AtlasTile>> {
+    pub fn get_tile(&mut self, c: char, atlas: &mut SpriteAtlas) -> Result<Option<&AtlasTile>> {
         if self.char_map.contains_key(&c) {
-            return Ok(self.char_map.get_mut(&c));
+            return Ok(self.char_map.get(&c));
         }
 
         if let Some(tile_name) = char_to_tile_name(c) {
@@ -113,7 +113,7 @@ impl TextTexture {
                 .get_tile(&tile_name)
                 .ok_or(GameError::Texture(TextureError::AtlasTileNotFound(tile_name)))?;
             self.char_map.insert(c, tile);
-            Ok(self.char_map.get_mut(&c))
+            Ok(self.char_map.get(&c))
         } else {
             Ok(None)
         }

tests/formatting.rs

@@ -0,0 +1,135 @@
+use pacman::systems::formatting::format_timing_display;
+use std::time::Duration;
+
+#[test]
+fn test_basic_formatting() {
+    let timing_data = vec![
+        ("60 FPS".to_string(), Duration::from_micros(1234), Duration::from_micros(567)),
+        ("input".to_string(), Duration::from_micros(123), Duration::from_micros(45)),
+        ("player".to_string(), Duration::from_micros(456), Duration::from_micros(123)),
+        ("movement".to_string(), Duration::from_micros(789), Duration::from_micros(234)),
+        ("render".to_string(), Duration::from_micros(12), Duration::from_micros(3)),
+        ("debug".to_string(), Duration::from_nanos(1000000), Duration::from_nanos(1000)),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Basic formatting test:");
+    println!("{}", result);
+    println!();
+}
+
+#[test]
+fn test_desired_format() {
+    // This test represents the exact format you want to achieve
+    let timing_data = vec![
+        ("total".to_string(), Duration::from_micros(1230), Duration::from_micros(570)),
+        ("input".to_string(), Duration::from_micros(120), Duration::from_micros(50)),
+        ("player".to_string(), Duration::from_micros(460), Duration::from_micros(120)),
+        ("movement".to_string(), Duration::from_micros(790), Duration::from_micros(230)),
+        ("render".to_string(), Duration::from_micros(10), Duration::from_micros(3)),
+        ("debug".to_string(), Duration::from_nanos(1000000), Duration::from_nanos(1000)),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Desired format test:");
+    println!("{}", result);
+    println!();
+
+    // Expected output should look like:
+    // total    :    1.23 ms ±    0.57 ms
+    // input    :    0.12 ms ±    0.05 ms
+    // player   :    0.46 ms ±    0.12 ms
+    // movement :    0.79 ms ±    0.23 ms
+    // render   :    0.01 ms ±    0.003ms
+    // debug    :    0.001ms ±    0.000ms
+}
+
+#[test]
+fn test_mixed_units() {
+    let timing_data = vec![
+        ("60 FPS".to_string(), Duration::from_millis(16), Duration::from_micros(500)),
+        (
+            "fast_system".to_string(),
+            Duration::from_nanos(500000),
+            Duration::from_nanos(100000),
+        ),
+        (
+            "medium_system".to_string(),
+            Duration::from_micros(2500),
+            Duration::from_micros(500),
+        ),
+        ("slow_system".to_string(), Duration::from_millis(5), Duration::from_millis(1)),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Mixed units test:");
+    println!("{}", result);
+    println!();
+}
+
+#[test]
+fn test_trailing_zeros() {
+    let timing_data = vec![
+        ("60 FPS".to_string(), Duration::from_micros(1000), Duration::from_micros(500)),
+        ("exact_ms".to_string(), Duration::from_millis(1), Duration::from_micros(100)),
+        ("exact_us".to_string(), Duration::from_micros(1), Duration::from_nanos(100000)),
+        ("exact_ns".to_string(), Duration::from_nanos(1000), Duration::from_nanos(100)),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Trailing zeros test:");
+    println!("{}", result);
+    println!();
+}
+
+#[test]
+fn test_edge_cases() {
+    let timing_data = vec![
+        ("60 FPS".to_string(), Duration::from_nanos(1), Duration::from_nanos(1)),
+        ("very_small".to_string(), Duration::from_nanos(100), Duration::from_nanos(50)),
+        ("very_large".to_string(), Duration::from_secs(1), Duration::from_millis(100)),
+        ("zero_time".to_string(), Duration::ZERO, Duration::ZERO),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Edge cases test:");
+    println!("{}", result);
+    println!();
+}
+
+#[test]
+fn test_variable_name_lengths() {
+    let timing_data = vec![
+        ("60 FPS".to_string(), Duration::from_micros(1234), Duration::from_micros(567)),
+        ("a".to_string(), Duration::from_micros(123), Duration::from_micros(45)),
+        (
+            "very_long_system_name".to_string(),
+            Duration::from_micros(456),
+            Duration::from_micros(123),
+        ),
+        ("medium".to_string(), Duration::from_micros(789), Duration::from_micros(234)),
+    ];
+
+    let result = format_timing_display(timing_data);
+    println!("Variable name lengths test:");
+    println!("{}", result);
+    println!();
+}
+
+#[test]
+fn test_empty_input() {
+    let timing_data = vec![];
+    let result = format_timing_display(timing_data);
+    assert_eq!(result, "");
+    println!("Empty input test: PASS");
+}
+
+#[test]
+fn test_single_entry() {
+    let timing_data = vec![("60 FPS".to_string(), Duration::from_micros(1234), Duration::from_micros(567))];
+
+    let result = format_timing_display(timing_data);
+    println!("Single entry test:");
+    println!("{}", result);
+    println!();
+}

tests/graph.rs

@@ -1,5 +1,5 @@
 use pacman::entity::direction::Direction;
-use pacman::entity::graph::{EdgePermissions, Graph, Node};
+use pacman::entity::graph::{Graph, Node, TraversalFlags};
 
 fn create_test_graph() -> Graph {
     let mut graph = Graph::new();
@@ -78,11 +78,11 @@ fn test_graph_edge_permissions() {
     });
 
     graph
-        .add_edge(node1, node2, false, None, Direction::Right, EdgePermissions::GhostsOnly)
+        .add_edge(node1, node2, false, None, Direction::Right, TraversalFlags::GHOST)
         .unwrap();
 
     let edge = graph.find_edge_in_direction(node1, Direction::Right).unwrap();
-    assert_eq!(edge.permissions, EdgePermissions::GhostsOnly);
+    assert_eq!(edge.traversal_flags, TraversalFlags::GHOST);
 }
 
 #[test]
@@ -118,21 +118,21 @@ fn should_error_on_negative_edge_distance() {
         position: glam::Vec2::new(16.0, 0.0),
     });
 
-    let result = graph.add_edge(node1, node2, false, Some(-1.0), Direction::Right, EdgePermissions::All);
+    let result = graph.add_edge(node1, node2, false, Some(-1.0), Direction::Right, TraversalFlags::ALL);
     assert!(result.is_err());
 }
 
 #[test]
 fn should_error_on_duplicate_edge_without_replace() {
     let mut graph = create_test_graph();
-    let result = graph.add_edge(0, 1, false, None, Direction::Right, EdgePermissions::All);
+    let result = graph.add_edge(0, 1, false, None, Direction::Right, TraversalFlags::ALL);
     assert!(result.is_err());
 }
 
 #[test]
 fn should_allow_replacing_an_edge() {
     let mut graph = create_test_graph();
-    let result = graph.add_edge(0, 1, true, Some(42.0), Direction::Right, EdgePermissions::All);
+    let result = graph.add_edge(0, 1, true, Some(42.0), Direction::Right, TraversalFlags::ALL);
     assert!(result.is_ok());
 
     let edge = graph.find_edge(0, 1).unwrap();

tests/profiling.rs

@@ -0,0 +1,40 @@
+use pacman::systems::profiling::SystemTimings;
+use std::time::Duration;
+
+#[test]
+fn test_timing_statistics() {
+    let timings = SystemTimings::default();
+
+    // Add some test data
+    timings.add_timing("test_system", Duration::from_millis(10));
+    timings.add_timing("test_system", Duration::from_millis(12));
+    timings.add_timing("test_system", Duration::from_millis(8));
+
+    let stats = timings.get_stats();
+    let (avg, std_dev) = stats.get("test_system").unwrap();
+
+    // Average should be 10ms, standard deviation should be small
+    assert!((avg.as_millis() as f64 - 10.0).abs() < 1.0);
+    assert!(std_dev.as_millis() > 0);
+
+    let (total_avg, total_std) = timings.get_total_stats();
+    assert!((total_avg.as_millis() as f64 - 10.0).abs() < 1.0);
+    assert!(total_std.as_millis() > 0);
+}
+
+// #[test]
+// fn test_window_size_limit() {
+//     let timings = SystemTimings::default();
+
+//     // Add more than 90 timings to test window size limit
+//     for i in 0..100 {
+//         timings.add_timing("test_system", Duration::from_millis(i));
+//     }
+
+//     let stats = timings.get_stats();
+//     let (avg, _) = stats.get("test_system").unwrap();
+
+//     // Should only keep the last 90 values, so average should be around 55ms
+//     // (average of 10-99)
+//     assert!((avg.as_millis() as f64 - 55.0).abs() < 5.0);
+// }