Picking example (#177)

CHANGELOG.md

@@ -2,10 +2,11 @@
 
 ## [Unreleased]
 
-* Added `Hex::as_u64` and `Hex::from_u64`
+* Added `Hex::as_u64` and `Hex::from_u64` (#169)
 * Bumped `bevy` to 0.14.x (#173)
 * Bumped bevy ecosystem dependencies (#173)
 * Updated examples (#173)
+* Added a 3d picking exampe (#177)
 
 ## 0.17.0
 

Cargo.toml

@@ -45,20 +45,21 @@ optional = true
 [dev-dependencies.bevy]
 version = "0.14"
 features = [
-  "bevy_asset",
-  "bevy_winit",
-  "bevy_core_pipeline",
-  "bevy_pbr",
-  "bevy_render",
-  "bevy_sprite",
-  "bevy_text",
-  "default_font",
-  "png",
-  "x11",
-  "tonemapping_luts",
-  "bevy_gizmos",
-  # Faster compilation
-  "dynamic_linking",
+    "bevy_asset",
+    "bevy_winit",
+    "bevy_core_pipeline",
+    "bevy_pbr",
+    "bevy_render",
+    "bevy_sprite",
+    "bevy_text",
+    "default_font",
+    "png",
+    "x11",
+    "tonemapping_luts",
+    "bevy_gizmos",
+    "multi_threaded",
+    # Faster compilation
+    "dynamic_linking",
 ]
 default-features = false
 
@@ -104,6 +105,10 @@ path = "examples/field_of_movement.rs"
 name = "3d_columns"
 path = "examples/3d_columns.rs"
 
+[[example]]
+name = "3d_picking"
+path = "examples/3d_picking.rs"
+
 [[example]]
 name = "mesh_builder"
 path = "examples/mesh_builder.rs"

README.md

@@ -353,6 +353,14 @@ and how to use two layouts on the same grid.
  > `cargo run --example 3d_columns`
 
  This example showcases the 3d hexagon columns procedural generation
+
+### 3d picking 
+
+![picking](docs/3d_picking.png "3d picking example")
+
+ > `cargo run --example 3d_picking`
+ 
+This example showcases how to use the camera ray to detect hovered 3d columns
 
 ### Mesh builder
 

examples/3d_picking.rs

@@ -0,0 +1,139 @@
+use bevy::{
+    color::palettes::css::{WHITE, YELLOW},
+    prelude::*,
+    render::{mesh::Indices, render_asset::RenderAssetUsages, render_resource::PrimitiveTopology},
+    utils::HashMap,
+    window::PrimaryWindow,
+};
+use hexx::{shapes, *};
+use light_consts::lux;
+
+/// World size of the hexagons (outer radius)
+const HEX_SIZE: Vec2 = Vec2::splat(1.0);
+/// World space height of hex columns
+const COLUMN_HEIGHT: f32 = 10.0;
+/// Map radius
+const MAP_RADIUS: u32 = 20;
+
+pub fn main() {
+    App::new()
+        .insert_resource(AmbientLight {
+            brightness: lux::OFFICE,
+            ..default()
+        })
+        .add_plugins(DefaultPlugins)
+        .add_systems(Startup, (setup_camera, setup_grid))
+        .add_systems(Update, higlight_hovered)
+        .run();
+}
+
+#[derive(Debug, Resource)]
+struct Map {
+    layout: HexLayout,
+    entities: HashMap<Hex, Entity>,
+    highlighted_material: Handle<StandardMaterial>,
+    default_material: Handle<StandardMaterial>,
+}
+
+/// 3D Orthogrpahic camera setup
+fn setup_camera(mut commands: Commands) {
+    let transform = Transform::from_xyz(0.0, 60.0, 60.0).looking_at(Vec3::ZERO, Vec3::Y);
+    commands.spawn(Camera3dBundle {
+        transform,
+        ..default()
+    });
+    let transform = Transform::from_xyz(60.0, 60.0, 00.0).looking_at(Vec3::ZERO, Vec3::Y);
+    commands.spawn(DirectionalLightBundle {
+        transform,
+        ..default()
+    });
+}
+
+/// Hex grid setup
+fn setup_grid(
+    mut commands: Commands,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+) {
+    let layout = HexLayout {
+        hex_size: HEX_SIZE,
+        ..default()
+    };
+    // materials
+    let default_material = materials.add(Color::Srgba(WHITE));
+    let highlighted_material = materials.add(Color::Srgba(YELLOW));
+    // mesh
+    let mesh = hexagonal_column(&layout);
+    let mesh_handle = meshes.add(mesh);
+
+    let entities = shapes::hexagon(Hex::ZERO, MAP_RADIUS)
+        .map(|hex| {
+            let pos = layout.hex_to_world_pos(hex);
+            let id = commands
+                .spawn(PbrBundle {
+                    transform: Transform::from_xyz(pos.x, -COLUMN_HEIGHT, pos.y),
+                    mesh: mesh_handle.clone(),
+                    material: default_material.clone_weak(),
+                    ..default()
+                })
+                .id();
+            (hex, id)
+        })
+        .collect();
+    commands.insert_resource(Map {
+        layout,
+        entities,
+        highlighted_material,
+        default_material,
+    });
+}
+
+fn higlight_hovered(
+    mut commands: Commands,
+    map: Res<Map>,
+    mut highlighted: Local<Hex>,
+    cameras: Query<(&Camera, &GlobalTransform)>,
+    windows: Query<&Window, With<PrimaryWindow>>,
+) {
+    let window = windows.single();
+    let (camera, cam_transform) = cameras.single();
+    let Some(ray) = window
+        .cursor_position()
+        .and_then(|p| camera.viewport_to_world(cam_transform, p))
+    else {
+        return;
+    };
+    let Some(distance) = ray.intersect_plane(Vec3::ZERO, InfinitePlane3d::new(Dir3::Y)) else {
+        return;
+    };
+    let point = ray.origin + ray.direction * distance;
+    let coord = map.layout.world_pos_to_hex(point.xz());
+    if coord != *highlighted {
+        let Some(entity) = map.entities.get(&coord).copied() else {
+            return;
+        };
+        commands
+            .entity(entity)
+            .insert(map.highlighted_material.clone_weak());
+        commands
+            .entity(map.entities[&*highlighted])
+            .insert(map.default_material.clone_weak());
+        *highlighted = coord;
+    }
+}
+
+/// Compute a bevy mesh from the layout
+fn hexagonal_column(hex_layout: &HexLayout) -> Mesh {
+    let mesh_info = ColumnMeshBuilder::new(hex_layout, COLUMN_HEIGHT)
+        .without_bottom_face()
+        .center_aligned()
+        .build();
+    Mesh::new(
+        PrimitiveTopology::TriangleList,
+        RenderAssetUsages::RENDER_WORLD,
+    )
+    .with_inserted_attribute(Mesh::ATTRIBUTE_POSITION, mesh_info.vertices)
+    .with_inserted_attribute(Mesh::ATTRIBUTE_NORMAL, mesh_info.normals)
+    .with_inserted_attribute(Mesh::ATTRIBUTE_UV_0, mesh_info.uvs)
+    .with_inserted_indices(Indices::U16(mesh_info.indices))
+}

src/algorithms/pathfinding.rs

@@ -46,7 +46,7 @@ fn reconstruct_path(came_from: &HashMap<Hex, Hex>, end: Hex) -> Vec<Hex> {
 /// * `start` - start node
 /// * `end` - destination node
 /// * `cost` - cost function taking a node pair (`a` -> `b`) and returning the
-/// logical cost to go from `a` to `b`
+///   logical cost to go from `a` to `b`
 ///
 /// # Examples
 ///

src/hex/mod.rs

@@ -698,8 +698,7 @@ impl Hex {
     /// Find in which [`VertexDirection`] wedge `rhs` is relative to `self`.
     ///
     /// > This method can be innaccurate in case of a *tie* between directions,
-    /// > prefer
-    /// using [`Self::diagonal_way_to`] instead
+    /// > prefer using [`Self::diagonal_way_to`] instead
     pub fn main_diagonal_to(self, rhs: Self) -> VertexDirection {
         self.diagonal_way_to(rhs).unwrap()
     }
@@ -723,8 +722,7 @@ impl Hex {
     /// Find in which [`EdgeDirection`] wedge `rhs` is relative to `self`
     ///
     /// > This method can be innaccurate in case of a *tie* between directions,
-    /// > prefer
-    /// using [`Self::way_to`] for accuracy
+    /// > prefer using [`Self::way_to`] for accuracy
     #[must_use]
     pub fn main_direction_to(self, rhs: Self) -> EdgeDirection {
         self.way_to(rhs).unwrap()

src/mesh/utils.rs

@@ -108,8 +108,7 @@ impl<const VERTS: usize, const TRIS: usize> Face<VERTS, TRIS> {
     ///
     /// * `mode` - the insetting behaviour mode
     /// * `keep_inner_face` - If set to true the insetted face will be kept,
-    ///   otherwise
-    /// it will be removed
+    ///   otherwise it will be removed
     #[allow(clippy::cast_possible_truncation)]
     #[must_use]
     pub fn inset(self, mode: InsetScaleMode, scale: f32, keep_inner_face: bool) -> MeshInfo {