auto aim

src/aim.rs

@@ -0,0 +1,131 @@
+use crate::{
+    billboards::Billboard,
+    player::{Player, PlayerHead},
+    tb_entities::EnemySpawn,
+};
+use bevy::prelude::*;
+use bevy_sprite3d::{Sprite3dBuilder, Sprite3dParams};
+use std::f32::consts::PI;
+
+#[derive(Resource, Reflect)]
+#[reflect(Resource)]
+struct AimState {
+    pub target: Option<Entity>,
+    pub range: f32,
+    pub angle: f32,
+}
+
+impl Default for AimState {
+    fn default() -> Self {
+        Self {
+            target: None,
+            range: 40.,
+            angle: PI / 10.,
+        }
+    }
+}
+
+#[derive(Component, Reflect)]
+#[reflect(Component)]
+struct Marker;
+
+#[derive(Event)]
+enum MarkerEvent {
+    Spawn(Entity),
+    Despawn,
+}
+
+pub fn plugin(app: &mut App) {
+    app.init_resource::<AimState>();
+    app.add_systems(Update, update);
+    app.add_observer(marker_event);
+}
+
+fn marker_event(
+    trigger: Trigger<MarkerEvent>,
+    mut commands: Commands,
+    asset_server: Res<AssetServer>,
+    mut sprite_params: Sprite3dParams,
+    marker: Query<Entity, With<Marker>>,
+) {
+    for m in marker.iter() {
+        commands.entity(m).despawn_recursive();
+    }
+
+    let MarkerEvent::Spawn(target) = trigger.event() else {
+        return;
+    };
+
+    let selector = asset_server.load("ui/selector.png");
+
+    let id = commands
+        .spawn((
+            Name::new("aim-marker"),
+            Billboard,
+            Marker,
+            Transform::from_translation(Vec3::new(0., 3., 0.)),
+            Sprite3dBuilder {
+                image: selector,
+                pixels_per_metre: 30.,
+                alpha_mode: AlphaMode::Blend,
+                unlit: true,
+                ..default()
+            }
+            .bundle(&mut sprite_params),
+        ))
+        .id();
+
+    commands.entity(*target).add_child(id);
+}
+
+fn update(
+    mut commands: Commands,
+    mut state: ResMut<AimState>,
+    query: Query<(Entity, &Transform), With<EnemySpawn>>,
+    player_pos: Query<&Transform, With<Player>>,
+    player_rot: Query<&Transform, With<PlayerHead>>,
+) {
+    let Some(player_pos) = player_pos.iter().next().map(|t| t.translation) else {
+        return;
+    };
+
+    let Some(player_forward) = player_rot.iter().next().map(|t| t.forward()) else {
+        return;
+    };
+
+    let mut new_target = None;
+    let mut target_distance = f32::MAX;
+
+    for (e, t) in query.iter() {
+        let delta = player_pos - t.translation;
+
+        let distance = delta.length();
+
+        if distance > state.range {
+            continue;
+        }
+
+        let angle = player_forward.angle_between(delta.normalize());
+
+        if angle < state.angle && distance < target_distance {
+            new_target = Some(e);
+            target_distance = distance;
+        }
+    }
+
+    if let Some(e) = state.target {
+        if commands.get_entity(e).is_none() {
+            state.target = None;
+            return;
+        }
+    }
+
+    if new_target != state.target {
+        if let Some(target) = new_target {
+            commands.trigger(MarkerEvent::Spawn(target));
+        } else {
+            commands.trigger(MarkerEvent::Despawn);
+        }
+        state.target = new_target;
+    }
+}

src/main.rs

@@ -1,3 +1,4 @@
+mod aim;
 mod alien;
 mod billboards;
 mod camera;
@@ -74,6 +75,7 @@ fn main() {
     app.add_plugins(platforms::plugin);
     app.add_plugins(movables::plugin);
     app.add_plugins(billboards::plugin);
+    app.add_plugins(aim::plugin);
 
     app.insert_resource(AmbientLight {
         color: Color::WHITE,

src/player.rs

@@ -3,7 +3,6 @@ use std::{f32::consts::PI, time::Duration};
 use crate::{
     DebugVisuals,
     alien::{ALIEN_ASSET_PATH, Animations},
-    billboards::Billboard,
     camera::GameCameraRig,
     cash::{Cash, CashCollectEvent},
     heads_ui::HeadChanged,
@@ -16,7 +15,6 @@ use bevy::{
     window::{CursorGrabMode, PrimaryWindow},
 };
 use bevy_dolly::prelude::Rig;
-use bevy_sprite3d::{Sprite3dBuilder, Sprite3dParams};
 use bevy_tnua::{TnuaUserControlsSystemSet, prelude::*};
 use bevy_tnua_avian3d::TnuaAvian3dSensorShape;
 
@@ -27,10 +25,10 @@ pub struct Player;
 struct PlayerAnimations;
 
 #[derive(Component, Default)]
-struct PlayerHead;
+pub struct PlayerHead;
 
 #[derive(Component, Default)]
-struct PlayerRig;
+pub struct PlayerRig;
 
 #[derive(Resource, Default)]
 struct PlayerSpawned {
@@ -51,7 +49,7 @@ pub fn plugin(app: &mut App) {
         (
             spawn,
             update_camera,
-            cursor_events,
+            mouse_rotate,
             collect_cash,
             toggle_animation,
             setup_animations_marker_for_player,
@@ -70,7 +68,6 @@ fn spawn(
     asset_server: Res<AssetServer>,
     query: Query<&Transform, With<SpawnPoint>>,
     mut player_spawned: ResMut<PlayerSpawned>,
-    mut sprite_params: Sprite3dParams,
 ) {
     if player_spawned.spawned {
         return;
@@ -84,7 +81,6 @@ fn spawn(
 
     let mesh = asset_server
         .load(GltfAssetLabel::Scene(0).from_asset("models/heads/angry demonstrator.glb"));
-    let selector = asset_server.load("ui/selector.png");
 
     commands
         .spawn((
@@ -113,18 +109,6 @@ fn spawn(
                 .with_rotation(Quat::from_rotation_y(std::f32::consts::PI))
                 .with_scale(Vec3::splat(1.5)),
             SceneRoot(asset_server.load(GltfAssetLabel::Scene(0).from_asset(ALIEN_ASSET_PATH))),
-        ))
-        .with_child((
-            Billboard,
-            Transform::from_translation(Vec3::new(0., 1.5, 0.)),
-            Sprite3dBuilder {
-                image: selector,
-                pixels_per_metre: 40.,
-                alpha_mode: AlphaMode::Blend,
-                unlit: true,
-                ..default()
-            }
-            .bundle(&mut sprite_params),
         ));
 
     commands.spawn((
@@ -135,7 +119,7 @@ fn spawn(
     player_spawned.spawned = true;
 }
 
-fn cursor_events(
+fn mouse_rotate(
     mut mouse: EventReader<MouseMotion>,
     // todo: Put the player head as a child of the rig to avoid this mess:
     mut player: Query<&mut Transform, Or<(With<PlayerRig>, With<PlayerHead>)>>,

src/tb_entities.rs

@@ -94,6 +94,14 @@ impl EnemySpawn {
         };
 
         let this = world.get_entity(entity).unwrap().get::<Self>().unwrap();
+        let this_transform = world
+            .get_entity(entity)
+            .unwrap()
+            .get::<Transform>()
+            .unwrap();
+
+        let mut this_transform = *this_transform;
+        this_transform.translation += Vec3::new(0., 1., 0.);
 
         let mesh = asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/alien_naked.glb"));
 
@@ -103,23 +111,23 @@ impl EnemySpawn {
         world
             .commands()
             .entity(entity)
-            .insert((Name::from("Enemy"), Visibility::default()))
-            .with_children(|parent| {
-                parent
-                    .spawn((
+            .insert((
+                this_transform,
+                Name::from("Enemy"),
                 Visibility::default(),
                 RigidBody::Dynamic,
                 Collider::capsule(0.4, 2.),
                 LockedAxes::new().lock_rotation_z().lock_rotation_x(),
-                        Transform::from_translation(Vec3::new(0., 1.0, 0.)),
             ))
-                    .with_child((
+            .with_children(|parent| {
+                parent
+                    .spawn((
                         Transform::from_translation(Vec3::new(0., 1., 0.)),
                         SceneRoot(head_mesh),
                     ))
                     .with_child((
                         Visibility::default(),
-                        Transform::from_translation(Vec3::new(0., -1.4, 0.))
+                        Transform::from_translation(Vec3::new(0., -2.4, 0.))
                             .with_scale(Vec3::splat(1.5)),
                         SceneRoot(mesh),
                     ));