feat: Camera control

src/camera.rs

@@ -0,0 +1,108 @@
+use bevy::{input::mouse::{AccumulatedMouseMotion, AccumulatedMouseScroll}, prelude::*};
+use crate::grid::Grid;
+use std::{f32::consts::FRAC_PI_2,ops::Range};
+
+pub struct GameCameraPlugin;
+
+impl Plugin for GameCameraPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(Startup, scene.spawn())
+            .add_systems(Update, orbit);
+    }
+}
+
+#[derive(Clone,Component)]
+pub struct CameraOrbit {
+    pub distance: f32,
+    pub pitch_speed: f32,
+    pub pitch_range: Range<f32>,
+    pub yaw_speed: f32,
+    pub center_offset: Vec3,
+    pub vertical_offset_speed: f32,
+    pub horizontal_offset_speed: f32,
+}
+
+impl Default for CameraOrbit {
+    fn default() -> Self {
+        let limit = FRAC_PI_2 - 0.01;
+        Self {
+            distance: 20.,
+            yaw_speed: 0.004,
+            pitch_speed: 0.004,
+            pitch_range: -limit..limit,
+            center_offset: Vec3::ZERO,
+            vertical_offset_speed: 0.05,
+            horizontal_offset_speed: 0.05,
+        }
+    }
+}
+
+pub fn scene() -> impl SceneList {
+    bsn_list![
+        camera(),
+        sun()
+    ]
+}
+
+pub fn camera() -> impl Scene {
+    bsn! {
+        Camera3d
+        template(
+            |ctx| {
+                let grid = ctx.resource::<Grid>();
+                let center = grid.size.as_vec3() * 0.5;
+                Ok(Transform::from_xyz(
+                        center.x + grid.size.x as f32 * 1.2, 
+                        grid.size.y as f32 * 1.2, 
+                        center.z + grid.size.z as f32 * 1.2).looking_at(center, Vec3::Y))
+            }
+        )
+        CameraOrbit
+    }
+}
+
+pub fn sun() -> impl Scene {
+    bsn!{
+        DirectionalLight {
+            illuminance: 8_000.0,
+            shadow_maps_enabled: false,
+        }
+        template_value(Transform::from_xyz(10.0, 30.0, 10.0).looking_at(Vec3::ZERO, Vec3::Y))
+    }
+}
+
+pub fn orbit(
+    camera: Single<(&mut Transform,&mut CameraOrbit)>,
+    mouse_buttons: Res<ButtonInput<MouseButton>>,
+    mouse_motion: Res<AccumulatedMouseMotion>,
+    mouse_scroll: Res<AccumulatedMouseScroll>,
+    grid: Res<Grid>) {
+    
+    let (mut transform, mut orbit) = camera.into_inner();
+
+    if mouse_buttons.pressed(MouseButton::Right) {
+        let delta = mouse_motion.delta;
+        let (yaw, pitch, roll) = transform.rotation.to_euler(EulerRot::YXZ);
+        
+        let pitch = (pitch - delta.y * orbit.pitch_speed).clamp(orbit.pitch_range.start, orbit.pitch_range.end);
+        let yaw = yaw - delta.x * orbit.yaw_speed;
+
+        transform.rotation = Quat::from_euler(EulerRot::YXZ, yaw, pitch, roll);
+    }
+    if mouse_buttons.pressed(MouseButton::Middle) {
+        let delta = mouse_motion.delta;
+
+        let new_offset = transform.up() * delta.y * orbit.vertical_offset_speed - transform.right() * delta.x * orbit.horizontal_offset_speed;
+        orbit.center_offset += new_offset;
+    }
+
+    let center = grid.size.as_vec3() * 0.5;
+    let min_distance = vec3(
+            center.x + grid.size.x as f32 * 1.2, 
+            grid.size.y as f32 * 1.2, 
+            center.z + grid.size.z as f32 * 1.2).length();
+
+    orbit.distance = (orbit.distance-mouse_scroll.delta.y).max(min_distance);
+
+    transform.translation = center + orbit.center_offset -transform.forward() * orbit.distance;
+}

src/main.rs

@@ -1,4 +1,5 @@
 use bevy::prelude::*;
+use crate::camera::GameCameraPlugin;
 use crate::grid::Grid;
 use crate::simulation::SimulationPlugin;
 
@@ -7,12 +8,12 @@ use crate::view::ViewPlugin;
 pub mod simulation;
 pub mod view;
 pub mod grid;
+pub mod camera;
 
 fn main() {
     App::new()
         .add_plugins(DefaultPlugins)
-        .add_plugins(ViewPlugin)
-        .add_plugins(SimulationPlugin)
+        .add_plugins((ViewPlugin,SimulationPlugin,GameCameraPlugin))
         .insert_resource(Grid::cube(16))
         .run();
 }

src/view/game.rs

@@ -11,7 +11,7 @@ impl Plugin for GameViewPlugin {
         app.add_systems(PreStartup, debug_setup_grid)
             .init_resource::<CubeStages>()
             .init_resource::<TileMaterials>()
-            .add_systems(Startup, (setup_view_cubes, scene.spawn()))
+            .add_systems(Startup, setup_view_cubes)
             .add_systems(Update, update_cubes);
     }
 }
@@ -84,38 +84,6 @@ pub fn setup_view_cubes(
     }
 }
 
-pub fn scene() -> impl SceneList {
-    bsn_list![
-        camera(),
-        sun()
-    ]
-}
-
-pub fn camera() -> impl Scene {
-    bsn! {
-        Camera3d
-        template(
-            |ctx| {
-                let grid = ctx.resource::<Grid>();
-                let center = grid.size.as_vec3() * 0.5;
-                Ok(Transform::from_xyz(
-                        center.x + grid.size.x as f32 * 1.5, 
-                        grid.size.y as f32 * 1.5, 
-                        center.z + grid.size.z as f32 * 1.5).looking_at(center, Vec3::Y))
-            }
-        )
-    }
-}
-
-pub fn sun() -> impl Scene {
-    bsn!{
-        DirectionalLight {
-            illuminance: 8_000.0,
-            shadow_maps_enabled: false,
-        }
-        template_value(Transform::from_xyz(10.0, 30.0, 10.0).looking_at(Vec3::ZERO, Vec3::Y))
-    }
-}
 
 
 pub fn cube(position: Vec3,index: usize,mesh: Handle<Mesh>) -> impl Scene {