From 1c787d17ff920c21fc32161e13b78bfa36e7b057 Mon Sep 17 00:00:00 2001
From: Daniel Flanagan <daniel@lyte.dev>
Date: Wed, 20 Dec 2023 13:36:34 -0600
Subject: [PATCH] WIP movement

---
 src/main.rs     |  2 ++
 src/movement.rs | 40 ++++++++++++++++++++++++++++++++++
 src/player.rs   | 57 +++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 99 insertions(+)
 create mode 100644 src/movement.rs
 create mode 100644 src/player.rs

diff --git a/src/main.rs b/src/main.rs
index 9b6dcd8..4110b9c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,6 +2,8 @@ use bevy::prelude::*;
 
 mod assets;
 mod camera;
+mod movement;
+mod player;
 
 fn main() {
     let mut app = App::new();
diff --git a/src/movement.rs b/src/movement.rs
new file mode 100644
index 0000000..a70dece
--- /dev/null
+++ b/src/movement.rs
@@ -0,0 +1,40 @@
+use bevy::prelude::*;
+
+pub struct MovementPlugin;
+
+#[derive(Component, Debug, Default)]
+pub struct Velocity(Vec2);
+
+#[derive(Component, Debug, Default)]
+pub struct Heading(Vec2);
+
+#[derive(Component, Debug, Default)]
+pub struct Speed(f32);
+
+impl Velocity {
+    pub fn from_speed_heading(heading: Vec2, speed: f32) -> Self {
+        Self(heading.normalize_or_zero() * speed)
+    }
+
+    pub fn new(x: f32, y: f32) -> Self {
+        Self(Vec2::new(x, y))
+    }
+}
+
+#[derive(Bundle, Debug, Default)]
+pub struct MovementBundle {
+    pub velocity: Velocity,
+}
+
+impl Plugin for MovementPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(Update, update_position);
+    }
+}
+
+fn update_position(mut query: Query<(&Velocity, &mut Transform)>, time: Res<Time>) {
+    for (velocity, mut transform) in query.iter_mut() {
+        // TODO: convert vec2 to vec3 with a zero Z value?
+        transform.translation += velocity.0 * time.delta_seconds();
+    }
+}
diff --git a/src/player.rs b/src/player.rs
new file mode 100644
index 0000000..fc4058c
--- /dev/null
+++ b/src/player.rs
@@ -0,0 +1,57 @@
+use bevy::prelude::*;
+
+use crate::{
+    assets::Assets,
+    movement::{MovementBundle, Velocity},
+};
+
+const PLAYER_SPEED: f32 = 50.;
+
+pub struct PlayerPlugin;
+
+impl Plugin for PlayerPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(PostStartup, spawn_player)
+            .add_systems(Update, player_movement);
+    }
+}
+
+#[derive(Component, Debug)]
+pub struct Player;
+
+fn spawn_player(mut commands: Commands, sprite_assets: Res<SpriteAssets>) {
+    commands.spawn((
+        Player,
+        SpriteBundle {
+            texture: sprite_assets.knight.clone(),
+            transform: Transform::from_xyz(0., 0., 0.),
+            ..Default::default()
+        },
+        MovementBundle {
+            velocity: Velocity::new(0., 0.),
+        },
+    ));
+}
+
+fn player_movement(mut query: Query<&mut Velocity, With<Player>>, input: Res<Input<KeyCode>>) {
+    let mut direction = Vec3::ZERO;
+    for key in input.get_pressed() {
+        match key {
+            KeyCode::W | KeyCode::Up => {
+                direction += Vec3::Y;
+            }
+            KeyCode::A | KeyCode::Left => {
+                direction += Vec3::NEG_X;
+            }
+            KeyCode::S | KeyCode::Down => {
+                direction += Vec3::NEG_Y;
+            }
+            KeyCode::D | KeyCode::Right => {
+                direction += Vec3::X;
+            }
+            _ => {}
+        }
+    }
+    let mut velocity = query.single_mut();
+    velocity.change_direction_speed(direction, PLAYER_SPEED);
+}