network code and stuff

Cargo.toml

@@ -1,3 +1,3 @@
 [workspace]
 resolver = "2"
-members = ["client", "server"]
+members = ["client", "server", "shared"]

client/Cargo.toml

@@ -5,6 +5,11 @@ edition = "2021"
 
 [dependencies]
 bevy = "0.8"
+bevy_renet = "0.0.5"
+bevy_egui = "0.15.0"
+renet_visualizer = "0.0.2"
+bincode = "1.3.1"
+daggmask-shared = { path = "../shared" }
 
 # Enable a small amount of optimization in debug mode
 [profile.dev]

client/src/main.rs

@@ -1,59 +1,246 @@
-use bevy::prelude::*;
+use std::{collections::HashMap, net::UdpSocket, time::SystemTime};
 
-fn main() {
-    App::new()
-        .add_plugins(DefaultPlugins)
-        .add_startup_system(setup)
-        .add_startup_system(spawn_player)
-        .add_system(move_player)
-        .run();
+use bevy::{
+    diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
+    prelude::*,
+};
+
+use bevy_egui::{EguiContext, EguiPlugin};
+use bevy_renet::{
+    renet::{ClientAuthentication, RenetClient, RenetError},
+    run_if_client_connected, RenetClientPlugin,
+};
+
+use daggmask_shared::{
+    client_connection_config, setup_level, ClientChannel, NetworkFrame, PlayerCommand, PlayerInput,
+    ServerChannel, ServerMessages, PROTOCOL_ID,
+};
+
+use renet_visualizer::{RenetClientVisualizer, RenetVisualizerStyle};
+
+#[derive(Component)]
+struct ControlledPlayer;
+
+#[derive(Default)]
+struct NetworkMapping(HashMap<Entity, Entity>);
+
+#[derive(Debug)]
+struct PlayerInfo {
+    client_entity: Entity,
+    server_entity: Entity,
 }
 
-fn setup(mut commands: Commands) {
-    info!("hehe");
-    let mut camera_bundle = Camera2dBundle::default();
-    camera_bundle.projection.scale = 1. / 50.;
-    commands.spawn_bundle(camera_bundle);
+#[derive(Debug, Default)]
+struct ClientLobby {
+    players: HashMap<u64, PlayerInfo>,
+}
+
+#[derive(Debug)]
+struct MostRecentTick(Option<u32>);
+
+fn new_renet_client() -> RenetClient {
+    let server_addr = "127.0.0.1:5000".parse().unwrap();
+    let socket = UdpSocket::bind("127.0.0.1:0").unwrap();
+    let connection_config = client_connection_config();
+    let current_time = SystemTime::now()
+        .duration_since(SystemTime::UNIX_EPOCH)
+        .unwrap();
+    let client_id = current_time.as_millis() as u64;
+    let authentication = ClientAuthentication::Unsecure {
+        client_id,
+        protocol_id: PROTOCOL_ID,
+        server_addr,
+        user_data: None,
+    };
+
+    RenetClient::new(current_time, socket, 1, connection_config, authentication).unwrap()
+}
+
+fn main() {
+    let mut app = App::new();
+    app.add_plugins(DefaultPlugins);
+    app.add_plugin(RenetClientPlugin);
+    app.add_plugin(TransformPlugin);
+    app.add_plugin(FrameTimeDiagnosticsPlugin::default());
+    app.add_plugin(LogDiagnosticsPlugin::default());
+    app.add_plugin(EguiPlugin);
+
+    app.add_event::<PlayerCommand>();
+
+    app.insert_resource(ClientLobby::default());
+    app.insert_resource(PlayerInput::default());
+    app.insert_resource(MostRecentTick(None));
+    app.insert_resource(new_renet_client());
+    app.insert_resource(RenetClientVisualizer::<200>::new(
+        RenetVisualizerStyle::default(),
+    ));
+    app.insert_resource(NetworkMapping::default());
+
+    app.add_system(player_input);
+    app.add_system(client_send_input.with_run_criteria(run_if_client_connected));
+    app.add_system(client_send_player_commands.with_run_criteria(run_if_client_connected));
+    app.add_system(client_sync_players.with_run_criteria(run_if_client_connected));
+    app.add_system(update_visulizer_system);
+
+    app.add_startup_system(setup_level);
+    app.add_system(panic_on_error_system);
+
+    app.run();
+}
+
+// If any error is found we just panic
+fn panic_on_error_system(mut renet_error: EventReader<RenetError>) {
+    for e in renet_error.iter() {
+        panic!("{}", e);
+    }
+}
+
+fn update_visulizer_system(
+    mut egui_context: ResMut<EguiContext>,
+    mut visualizer: ResMut<RenetClientVisualizer<200>>,
+    client: Res<RenetClient>,
+    mut show_visualizer: Local<bool>,
+    keyboard_input: Res<Input<KeyCode>>,
+) {
+    visualizer.add_network_info(client.network_info());
+    if keyboard_input.just_pressed(KeyCode::F1) {
+        *show_visualizer = !*show_visualizer;
+    }
+    if *show_visualizer {
+        visualizer.show_window(egui_context.ctx_mut());
+    }
+}
+
+fn player_input(
+    keyboard_input: Res<Input<KeyCode>>,
+    mut player_input: ResMut<PlayerInput>,
+    mouse_button_input: Res<Input<MouseButton>>,
+    target_query: Query<&Transform, With<Target>>,
+    mut player_commands: EventWriter<PlayerCommand>,
+    most_recent_tick: Res<MostRecentTick>,
+) {
+    player_input.left = keyboard_input.pressed(KeyCode::A) || keyboard_input.pressed(KeyCode::Left);
+    player_input.right =
+        keyboard_input.pressed(KeyCode::D) || keyboard_input.pressed(KeyCode::Right);
+    player_input.up = keyboard_input.pressed(KeyCode::W) || keyboard_input.pressed(KeyCode::Up);
+    player_input.down = keyboard_input.pressed(KeyCode::S) || keyboard_input.pressed(KeyCode::Down);
+    player_input.most_recent_tick = most_recent_tick.0;
+
+    if mouse_button_input.just_pressed(MouseButton::Left) {
+        player_commands.send(PlayerCommand::BasicAttack {
+            cast_at: Vec2::default(), // TODO: spawn projectiles correctly
+        });
+    }
+}
+
+fn client_send_input(player_input: Res<PlayerInput>, mut client: ResMut<RenetClient>) {
+    let input_message = bincode::serialize(&*player_input).unwrap();
+
+    client.send_message(ClientChannel::Input.id(), input_message);
+}
+
+fn client_send_player_commands(
+    mut player_commands: EventReader<PlayerCommand>,
+    mut client: ResMut<RenetClient>,
+) {
+    for command in player_commands.iter() {
+        let command_message = bincode::serialize(command).unwrap();
+        client.send_message(ClientChannel::Command.id(), command_message);
+    }
+}
+
+fn client_sync_players(
+    mut commands: Commands,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+    mut client: ResMut<RenetClient>,
+    mut lobby: ResMut<ClientLobby>,
+    mut network_mapping: ResMut<NetworkMapping>,
+    mut most_recent_tick: ResMut<MostRecentTick>,
+) {
+    let client_id = client.client_id();
+    while let Some(message) = client.receive_message(ServerChannel::ServerMessages.id()) {
+        let server_message = bincode::deserialize(&message).unwrap();
+        match server_message {
+            ServerMessages::PlayerCreate {
+                id,
+                translation,
+                entity,
+            } => {
+                println!("Player {} connected.", id);
+                let mut client_entity = commands.spawn_bundle(PbrBundle {
+                    mesh: meshes.add(Mesh::from(shape::Capsule::default())),
+                    material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()),
+                    transform: Transform::from_xyz(translation[0], translation[1], translation[2]),
+                    ..Default::default()
+                });
+
+                if client_id == id {
+                    client_entity.insert(ControlledPlayer);
+                }
+
+                let player_info = PlayerInfo {
+                    server_entity: entity,
+                    client_entity: client_entity.id(),
+                };
+                lobby.players.insert(id, player_info);
+                network_mapping.0.insert(entity, client_entity.id());
+            }
+            ServerMessages::PlayerRemove { id } => {
+                println!("Player {} disconnected.", id);
+                if let Some(PlayerInfo {
+                    server_entity,
+                    client_entity,
+                }) = lobby.players.remove(&id)
+                {
+                    commands.entity(client_entity).despawn();
+                    network_mapping.0.remove(&server_entity);
+                }
+            }
+            ServerMessages::SpawnProjectile {
+                entity,
+                location,
+                direction,
+            } => {
+                let projectile_entity = commands.spawn_bundle(SpriteBundle {
+                    sprite: Sprite {
+                        color: Color::rgb(0.25, 0.25, 0.75),
+                        custom_size: Some(Vec2::new(50.0, 100.0)),
+                        ..default()
+                    },
+                    ..default()
+                });
+
+                network_mapping.0.insert(entity, projectile_entity.id());
+            }
+            ServerMessages::DespawnProjectile { entity } => {
+                if let Some(entity) = network_mapping.0.remove(&entity) {
+                    commands.entity(entity).despawn();
+                }
+            }
+        }
+    }
+
+    while let Some(message) = client.receive_message(ServerChannel::NetworkFrame.id()) {
+        let frame: NetworkFrame = bincode::deserialize(&message).unwrap();
+        match most_recent_tick.0 {
+            None => most_recent_tick.0 = Some(frame.tick),
+            Some(tick) if tick < frame.tick => most_recent_tick.0 = Some(frame.tick),
+            _ => continue,
+        }
+
+        for i in 0..frame.entities.entities.len() {
+            if let Some(entity) = network_mapping.0.get(&frame.entities.entities[i]) {
+                let translation = frame.entities.translations[i].into();
+                let transform = Transform {
+                    translation,
+                    ..Default::default()
+                };
+                commands.entity(*entity).insert(transform);
+            }
+        }
+    }
 }
 
 #[derive(Component)]
-struct Player;
-
-fn spawn_player(mut commands: Commands) {
-    commands
-        .spawn_bundle(SpriteBundle {
-            sprite: Sprite {
-                color: Color::rgb(0., 0.47, 1.),
-                custom_size: Some(Vec2::new(1., 1.)),
-                ..Default::default()
-            },
-            ..Default::default()
-        })
-        .insert(Player);
-}
-
-fn move_player(keys: Res<Input<KeyCode>>, mut player_query: Query<&mut Transform, With<Player>>) {
-    let mut direction = Vec2::ZERO;
-    if keys.any_pressed([KeyCode::Up, KeyCode::W]) {
-        direction.y += 1.;
-    }
-    if keys.any_pressed([KeyCode::Down, KeyCode::S]) {
-        direction.y -= 1.;
-    }
-    if keys.any_pressed([KeyCode::Right, KeyCode::D]) {
-        direction.x += 1.;
-    }
-    if keys.any_pressed([KeyCode::Left, KeyCode::A]) {
-        direction.x -= 1.;
-    }
-    if direction == Vec2::ZERO {
-        return;
-    }
-
-    let move_speed = 0.13;
-    let move_delta = (direction * move_speed).extend(0.);
-
-    for mut transform in player_query.iter_mut() {
-        transform.translation += move_delta;
-    }
-}
+struct Target;

server/Cargo.toml

@@ -3,5 +3,12 @@ name = "daggmask-server"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[dependencies]
+bevy = "0.8.0"
+bevy_renet = "0.0.5"
+bevy_egui = "0.15.0"
+bevy_rapier2d = "0.16.0"
+renet_visualizer = "0.0.2"
+bincode = "1.3.1"
 
+daggmask-shared = { path = "../shared" }

server/src/main.rs

@@ -1,45 +1,291 @@
-use std::net::UdpSocket;
+use std::{collections::HashMap, net::UdpSocket, time::SystemTime};
 
-fn main() -> std::io::Result<()> {
-    // replace xxxx with your desired port
-    // replace S.S.S.S with your server address
-    let socket = UdpSocket::bind("S.S.S.S:xxxx")?;
-    let mut peers: Vec<String> = vec![];
+use bevy::{
+    diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
+    prelude::*,
+};
 
-    loop {
-        let mut buf = [0; 1024];
-        let (_, src) = socket.recv_from(&mut buf)?;
-        let stringified_buff = String::from_utf8(buf.to_vec()).unwrap();
-        let stringified_buff = stringified_buff.trim_matches(char::from(0));
+use bevy_egui::{EguiContext, EguiPlugin};
+use bevy_rapier2d::prelude::*;
+use bevy_renet::{
+    renet::{RenetServer, ServerAuthentication, ServerConfig, ServerEvent},
+    RenetServerPlugin,
+};
 
-        println!("[NEW MESSAGE]{:?} => {:?}", src, stringified_buff);
+use daggmask_shared::{
+    server_connection_config, setup_level, spawn_projectile, ClientChannel, NetworkFrame, Player,
+    PlayerCommand, PlayerInput, Projectile, ServerChannel, ServerMessages, PROTOCOL_ID,
+};
 
-        if stringified_buff != "register" {
-            continue;
+use renet_visualizer::RenetServerVisualizer;
+
+#[derive(Debug, Default)]
+pub struct ServerLobby {
+    pub players: HashMap<u64, Entity>,
+}
+
+#[derive(Debug, Default)]
+struct NetworkTick(u32);
+
+// Clients last received ticks
+#[derive(Debug, Default)]
+struct ClientTicks(HashMap<u64, Option<u32>>);
+
+const PLAYER_MOVE_SPEED: f32 = 5.0;
+
+fn new_renet_server() -> RenetServer {
+    let server_addr = "127.0.0.1:5000".parse().unwrap();
+    let socket = UdpSocket::bind(server_addr).unwrap();
+    let connection_config = server_connection_config();
+    let server_config =
+        ServerConfig::new(64, PROTOCOL_ID, server_addr, ServerAuthentication::Unsecure);
+    let current_time = SystemTime::now()
+        .duration_since(SystemTime::UNIX_EPOCH)
+        .unwrap();
+    RenetServer::new(current_time, server_config, connection_config, socket).unwrap()
+}
+
+fn main() {
+    let mut app = App::new();
+    app.add_plugins(DefaultPlugins);
+
+    app.add_plugin(RenetServerPlugin);
+    app.add_plugin(RapierPhysicsPlugin::<NoUserData>::default());
+    app.add_plugin(RapierDebugRenderPlugin::default());
+    app.add_plugin(FrameTimeDiagnosticsPlugin::default());
+    app.add_plugin(LogDiagnosticsPlugin::default());
+    app.add_plugin(EguiPlugin);
+
+    app.insert_resource(ServerLobby::default());
+    app.insert_resource(NetworkTick(0));
+    app.insert_resource(ClientTicks::default());
+    app.insert_resource(new_renet_server());
+    app.insert_resource(RenetServerVisualizer::<200>::default());
+
+    app.add_system(server_update_system);
+    app.add_system(server_network_sync);
+    app.add_system(move_players_system);
+    app.add_system(update_projectiles_system);
+    app.add_system(update_visulizer_system);
+    app.add_system(despawn_projectile_system);
+    app.add_system_to_stage(CoreStage::PostUpdate, projectile_on_removal_system);
+
+    app.add_startup_system(setup_level);
+    app.add_startup_system(setup_simple_camera);
+
+    app.run();
+}
+
+#[allow(clippy::too_many_arguments)]
+fn server_update_system(
+    mut server_events: EventReader<ServerEvent>,
+    mut commands: Commands,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+    mut lobby: ResMut<ServerLobby>,
+    mut server: ResMut<RenetServer>,
+    mut visualizer: ResMut<RenetServerVisualizer<200>>,
+    mut client_ticks: ResMut<ClientTicks>,
+    players: Query<(Entity, &Player, &Transform)>,
+) {
+    for event in server_events.iter() {
+        match event {
+            ServerEvent::ClientConnected(id, _) => {
+                println!("Player {} connected.", id);
+                visualizer.add_client(*id);
+
+                // Initialize other players for this new client
+                for (entity, player, transform) in players.iter() {
+                    let translation: [f32; 3] = transform.translation.into();
+                    let message = bincode::serialize(&ServerMessages::PlayerCreate {
+                        id: player.id,
+                        entity,
+                        translation,
+                    })
+                    .unwrap();
+                    server.send_message(*id, ServerChannel::ServerMessages.id(), message);
                 }
 
-        if !peers.contains(&format!("{}", src)) {
-            peers.push(format!("{}", src));
+                // Spawn new player
+                let transform = Transform::from_xyz(0., 0.51, 0.);
+                let player_entity = commands
+                    .spawn_bundle(PbrBundle {
+                        mesh: meshes.add(Mesh::from(shape::Capsule::default())),
+                        material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()),
+                        transform,
+                        ..Default::default()
+                    })
+                    .insert(RigidBody::Dynamic)
+                    .insert(LockedAxes::ROTATION_LOCKED | LockedAxes::TRANSLATION_LOCKED_Y)
+                    .insert(Collider::capsule_y(0.5, 0.5))
+                    .insert(PlayerInput::default())
+                    .insert(Velocity::default())
+                    .insert(Player {
+                        id: *id,
+                        location: Vec2::new(10., 10.),
+                    })
+                    .id();
+
+                lobby.players.insert(*id, player_entity);
+
+                let translation: [f32; 3] = transform.translation.into();
+                let message = bincode::serialize(&ServerMessages::PlayerCreate {
+                    id: *id,
+                    entity: player_entity,
+                    translation,
+                })
+                .unwrap();
+
+                server.broadcast_message(ServerChannel::ServerMessages.id(), message);
+            }
+            ServerEvent::ClientDisconnected(id) => {
+                println!("Player {} disconnected.", id);
+                visualizer.remove_client(*id);
+                client_ticks.0.remove(id);
+                if let Some(player_entity) = lobby.players.remove(id) {
+                    commands.entity(player_entity).despawn();
                 }
 
-        for p in &peers {
-            let filtered_peers = filter_peers(&peers, p);
+                let message =
+                    bincode::serialize(&ServerMessages::PlayerRemove { id: *id }).unwrap();
+                server.broadcast_message(ServerChannel::ServerMessages.id(), message);
+            }
+        }
+    }
 
-            if !filtered_peers.is_empty() {
-                socket.send_to(filtered_peers.join(",").as_bytes(), p)?;
+    for client_id in server.clients_id().into_iter() {
+        while let Some(message) = server.receive_message(client_id, ClientChannel::Command.id()) {
+            let command: PlayerCommand = bincode::deserialize(&message).unwrap();
+            match command {
+                PlayerCommand::BasicAttack { mut cast_at } => {
+                    println!(
+                        "Received basic attack from client {}: {:?}",
+                        client_id, cast_at
+                    );
+
+                    if let Some(player_entity) = lobby.players.get(&client_id) {
+                        if let Ok((_, _, player_transform)) = players.get(*player_entity) {
+                            cast_at[1] = player_transform.translation[1];
+
+                            let projectile_entity =
+                                spawn_projectile(&mut commands, cast_at, cast_at);
+
+                            let message = ServerMessages::SpawnProjectile {
+                                entity: projectile_entity,
+                                location: cast_at,
+                                direction: cast_at,
+                            };
+
+                            let message = bincode::serialize(&message).unwrap();
+                            server.broadcast_message(ServerChannel::ServerMessages.id(), message);
+                        }
+                    }
+                }
+            }
+        }
+
+        while let Some(message) = server.receive_message(client_id, ClientChannel::Input.id()) {
+            let input: PlayerInput = bincode::deserialize(&message).unwrap();
+            client_ticks.0.insert(client_id, input.most_recent_tick);
+
+            if let Some(player_entity) = lobby.players.get(&client_id) {
+                commands.entity(*player_entity).insert(input);
             }
         }
     }
 }
 
-fn filter_peers(peers: &Vec<String>, filter: &String) -> Vec<String> {
-    let mut new_peers: Vec<String> = vec![];
+fn update_projectiles_system(
+    mut commands: Commands,
+    mut projectiles: Query<(Entity, &mut Projectile)>,
+    time: Res<Time>,
+) {
+    for (entity, mut projectile) in projectiles.iter_mut() {
+        projectile.duration.tick(time.delta());
 
-    for p in peers {
-        if p != filter {
-            new_peers.push(String::from(p));
+        if projectile.duration.finished() {
+            commands.entity(entity).despawn();
         }
     }
-
-    new_peers
+}
+
+fn update_visulizer_system(
+    mut egui_context: ResMut<EguiContext>,
+    mut visualizer: ResMut<RenetServerVisualizer<200>>,
+    server: Res<RenetServer>,
+) {
+    visualizer.update(&server);
+    visualizer.show_window(egui_context.ctx_mut());
+}
+
+#[allow(clippy::type_complexity)]
+fn server_network_sync(
+    mut tick: ResMut<NetworkTick>,
+    mut server: ResMut<RenetServer>,
+    networked_entities: Query<(Entity, &Transform), Or<(With<Player>, With<Projectile>)>>,
+) {
+    let mut frame = NetworkFrame::default();
+
+    for (entity, transform) in networked_entities.iter() {
+        frame.entities.entities.push(entity);
+        frame
+            .entities
+            .translations
+            .push(transform.translation.into());
+    }
+
+    frame.tick = tick.0;
+    tick.0 += 1;
+
+    let sync_message = bincode::serialize(&frame).unwrap();
+
+    server.broadcast_message(ServerChannel::NetworkFrame.id(), sync_message);
+}
+
+fn move_players_system(mut query: Query<(&mut Velocity, &PlayerInput)>) {
+    for (mut velocity, input) in query.iter_mut() {
+        let x = (input.right as i8 - input.left as i8) as f32;
+        let y = (input.down as i8 - input.up as i8) as f32;
+        let direction = Vec2::new(x, y).normalize_or_zero();
+        velocity.linvel.x = direction.x * PLAYER_MOVE_SPEED;
+        velocity.linvel.y = direction.y * PLAYER_MOVE_SPEED;
+    }
+}
+
+pub fn setup_simple_camera(mut commands: Commands) {
+    // camera
+    commands.spawn_bundle(Camera3dBundle {
+        transform: Transform::from_xyz(-5.5, 5.0, 5.5).looking_at(Vec3::ZERO, Vec3::Y),
+        ..Default::default()
+    });
+}
+
+fn despawn_projectile_system(
+    mut commands: Commands,
+    mut collision_events: EventReader<CollisionEvent>,
+    projectile_query: Query<Option<&Projectile>>,
+) {
+    for collision_event in collision_events.iter() {
+        if let CollisionEvent::Started(entity1, entity2, _) = collision_event {
+            if let Ok(Some(_)) = projectile_query.get(*entity1) {
+                commands.entity(*entity1).despawn();
+            }
+
+            if let Ok(Some(_)) = projectile_query.get(*entity2) {
+                commands.entity(*entity2).despawn();
+            }
+        }
+    }
+}
+
+fn projectile_on_removal_system(
+    mut server: ResMut<RenetServer>,
+    removed_projectiles: RemovedComponents<Projectile>,
+) {
+    for entity in removed_projectiles.iter() {
+        let message = ServerMessages::DespawnProjectile { entity };
+        let message = bincode::serialize(&message).unwrap();
+
+        server.broadcast_message(ServerChannel::ServerMessages.id(), message);
+    }
 }

shared/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "daggmask-shared"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+bevy = "0.8.0"
+bevy_renet = "0.0.5"
+bevy_egui = "0.15.0"
+bevy_rapier2d = "0.16.0"
+serde = { version = "1.0", features = [ "derive" ] }

shared/src/lib.rs

@@ -0,0 +1,170 @@
+use std::time::Duration;
+
+use bevy::prelude::*;
+use bevy_renet::renet::{
+    ChannelConfig, ReliableChannelConfig, RenetConnectionConfig, UnreliableChannelConfig,
+    NETCODE_KEY_BYTES,
+};
+
+use bevy_rapier2d::geometry::Collider;
+use bevy_rapier2d::prelude::*;
+
+use serde::{Deserialize, Serialize};
+
+pub const PRIVATE_KEY: &[u8; NETCODE_KEY_BYTES] = b"en grisars katt hund hemlis key."; // 32-bytes
+pub const PROTOCOL_ID: u64 = 7;
+
+#[derive(Debug, Component)]
+pub struct Player {
+    pub id: u64,
+    pub location: Vec2,
+}
+
+#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize, Component)]
+pub struct PlayerInput {
+    pub most_recent_tick: Option<u32>,
+    pub up: bool,
+    pub down: bool,
+    pub left: bool,
+    pub right: bool,
+}
+
+#[derive(Debug, Serialize, Deserialize, Component)]
+pub enum PlayerCommand {
+    BasicAttack { cast_at: Vec2 },
+}
+
+pub enum ClientChannel {
+    Input,
+    Command,
+}
+
+pub enum ServerChannel {
+    ServerMessages,
+    NetworkFrame,
+}
+
+#[derive(Debug, Serialize, Deserialize, Component)]
+pub enum ServerMessages {
+    PlayerCreate {
+        entity: Entity,
+        id: u64,
+        translation: [f32; 3],
+    },
+    PlayerRemove {
+        id: u64,
+    },
+    SpawnProjectile {
+        entity: Entity,
+        location: Vec2,
+        direction: Vec2,
+    },
+    DespawnProjectile {
+        entity: Entity,
+    },
+}
+
+#[derive(Debug, Serialize, Deserialize, Default)]
+pub struct NetworkedEntities {
+    pub entities: Vec<Entity>,
+    pub translations: Vec<[f32; 3]>,
+}
+
+#[derive(Debug, Serialize, Deserialize, Default)]
+pub struct NetworkFrame {
+    pub tick: u32,
+    pub entities: NetworkedEntities,
+}
+
+impl ClientChannel {
+    pub fn id(&self) -> u8 {
+        match self {
+            Self::Input => 0,
+            Self::Command => 1,
+        }
+    }
+
+    pub fn channels_config() -> Vec<ChannelConfig> {
+        vec![
+            ReliableChannelConfig {
+                channel_id: Self::Input.id(),
+                message_resend_time: Duration::ZERO,
+                ..Default::default()
+            }
+            .into(),
+            ReliableChannelConfig {
+                channel_id: Self::Command.id(),
+                message_resend_time: Duration::ZERO,
+                ..Default::default()
+            }
+            .into(),
+        ]
+    }
+}
+
+impl ServerChannel {
+    pub fn id(&self) -> u8 {
+        match self {
+            Self::NetworkFrame => 0,
+            Self::ServerMessages => 1,
+        }
+    }
+
+    pub fn channels_config() -> Vec<ChannelConfig> {
+        vec![
+            UnreliableChannelConfig {
+                channel_id: Self::NetworkFrame.id(),
+                ..Default::default()
+            }
+            .into(),
+            ReliableChannelConfig {
+                channel_id: Self::ServerMessages.id(),
+                message_resend_time: Duration::from_millis(200),
+                ..Default::default()
+            }
+            .into(),
+        ]
+    }
+}
+
+pub fn client_connection_config() -> RenetConnectionConfig {
+    RenetConnectionConfig {
+        send_channels_config: ClientChannel::channels_config(),
+        receive_channels_config: ServerChannel::channels_config(),
+        ..Default::default()
+    }
+}
+
+pub fn server_connection_config() -> RenetConnectionConfig {
+    RenetConnectionConfig {
+        send_channels_config: ServerChannel::channels_config(),
+        receive_channels_config: ClientChannel::channels_config(),
+        ..Default::default()
+    }
+}
+
+/// set up the level
+pub fn setup_level(mut _commands: Commands) {
+    info!("bygger level...");
+}
+
+pub fn spawn_projectile(commands: &mut Commands, location: Vec2, direction: Vec2) -> Entity {
+    commands
+        .spawn()
+        .insert(Collider::ball(0.1))
+        .insert(Velocity::linear(direction * 10.))
+        .insert(ActiveEvents::COLLISION_EVENTS)
+        .insert(Projectile {
+            duration: Timer::from_seconds(1.5, false),
+            location,
+            direction,
+        })
+        .id()
+}
+
+#[derive(Debug, Component)]
+pub struct Projectile {
+    pub duration: Timer,
+    pub location: Vec2,
+    pub direction: Vec2,
+}