[Bug]: Incorrect normals when ray-casting using `cast_shape`

[AntonPieper]

I am trying to write a character controller using rapier. To control when I can jump, I want to use cast_shape to check whether I am currently grounded. This leads to a problem: the resulting normal is always Vec2(-0.0, 1.0) wven if I hit walls.

The relevant code of the system:

fn jump_controller(
    mut players: Query<(Entity, &mut Velocity, &Transform, &Collider), With<PlayerTag>>,
    keys: Res<Input<KeyCode>>,
    physics: Res<RapierContext>,
) {
    for (entity, mut velocity, transform, collider) in &mut players {
        let grounded = physics
            .cast_shape(
                transform.translation.truncate(),
                0.,
                Vec2::NEG_Y,
                collider,
                0.01,
                QueryFilter::new().exclude_collider(entity),
            )
            .is_some_and(|(_, collisions)| {
                println!("{:?}", collisions);
                (0.9..1.1).contains(&collisions.normal2.dot(Vec2::NEG_Y))
            });
        let mut movement = Vec2::default();
        if keys.pressed(KeyCode::Space) && grounded {
            movement.y += 200.;
        }
        velocity.linvel += movement;
    }
}

Full code (main.rs)

Here is my example code (important parts at lines 101 - 114 in the `jump_controller` function): ```rs use bevy::prelude::*; use bevy_rapier2d::prelude::*; use rand::prelude::*; #[derive(Bundle)] struct Enemy { #[bundle] sprite: SpriteBundle, collider: Collider, } #[derive(Component)] struct PlayerTag; #[derive(Component)] struct EnemyTag; const START_X: i32 = -10; const START_Y: i32 = 5; const END_Y: i32 = 20; const END_X: i32 = 10; fn create_player(mut commands: Commands) { commands .spawn(RigidBody::Dynamic) .insert(Collider::cuboid(5., 5.)) .insert(SpriteBundle { sprite: Sprite { color: Color::rgb(0.25, 0.25, 0.75), custom_size: Some(Vec2::new(10., 10.)), ..default() }, ..default() }) .insert(Velocity::default()) .insert(LockedAxes::ROTATION_LOCKED) .insert(GravityScale(1.)) .insert(Ccd::enabled()) .insert(PlayerTag {}); } fn create_camera(mut commands: Commands) { commands.spawn(Camera2dBundle::default()); } fn create_enemies(mut commands: Commands) { for y in START_Y..END_Y { for x in START_X..END_X { commands .spawn(SpriteBundle { transform: Transform::from_translation(Vec3::new( x as f32 * 21., y as f32 * 21., 0., )) .with_scale(Vec3::new(20., 20., 1.)), sprite: Sprite { color: Color::hsl(rand::thread_rng().gen_range(0. ..=360.), 1., 0.5), ..default() }, ..default() }) .insert(Collider::cuboid(0.5, 0.5)) .insert(EnemyTag {}); } } } fn create_ground(mut commands: Commands) { commands .spawn(SpriteBundle { sprite: Sprite { color: Color::Rgba { red: 0.5, green: 0.5, blue: 0.5, alpha: 1., }, ..default() }, transform: Transform::from_translation(Vec3::new(0., -100., 0.)) .with_scale(Vec3::new(1000., 100., 1.)), ..default() }) .insert(Collider::cuboid(0.5, 0.5)); } fn walk_controller(mut players: Query<&mut Velocity, With>, keys: Res>) { for mut velocity in &mut players { let mut movement = Vec2::default(); movement.x -= if keys.pressed(KeyCode::A) { 1. } else { 0. }; movement.x += if keys.pressed(KeyCode::D) { 1. } else { 0. }; movement = movement.normalize_or_zero(); velocity.linvel += movement; } } fn jump_controller( mut players: Query<(Entity, &mut Velocity, &Transform, &Collider), With>, keys: Res>, physics: Res, ) { for (entity, mut velocity, transform, collider) in &mut players { let grounded = physics .cast_shape( transform.translation.truncate(), 0., Vec2::NEG_Y, collider, 0.01, QueryFilter::new().exclude_collider(entity), ) .is_some_and(|(_, collisions)| { println!("{:?}", collisions); (0.9..1.1).contains(&collisions.normal2.dot(Vec2::NEG_Y)) }); let mut movement = Vec2::default(); if keys.pressed(KeyCode::Space) && grounded { movement.y += 200.; } velocity.linvel += movement; } } fn camera_controller( mut query: Query<&mut Transform, (With, Without)>, player: Query<&Transform, With>, ) { for mut camera_transform in &mut query { camera_transform.translation = player.single().translation; } } pub struct GamePlugin; impl Plugin for GamePlugin { fn build(&self, app: &mut App) { app.add_startup_systems((create_enemies, create_player, create_camera, create_ground)) .add_systems(( walk_controller, jump_controller, camera_controller.after(jump_controller), )); } } fn main() { App::new() .add_plugins(DefaultPlugins) .add_plugin(RapierPhysicsPlugin::::pixels_per_meter(100.0)) .add_plugin(RapierDebugRenderPlugin::default()) .add_plugin(GamePlugin) .run(); } ```

My Cargo config

**Cargo.toml** ```toml [package] name = "animation-programming" version = "0.1.0" edition = "2021" # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html [dependencies] bevy = { version = "0.10.1" } rand = "0.8.5" bevy_rapier2d = { version = "0.21.0", features = [ "simd-nightly", "debug-render-2d" ] } # Enable a small amount of optimization in debug mode [profile.dev] # opt-level = 1 [profile.release] lto = "thin" # Enable high optimizations for dependencies (incl. Bevy), but not for our code: [profile.dev.package."*"] opt-level = 3 ``` **rust-toolchain.toml** ```toml [toolchain] channel = "nightly" ```

[Aceeri]

Be careful to check the toi.status for TOIStatus::Penetrating here, the results are currently undefined if it is. Ideally I think we hide the Toi stuff behind an enum so you have to check the status, but that's on my TODO list currently.

[Aceeri]

Also be careful to check the normal1 vs normal2 of the Toi, I'm not entirely sure if normal2 is actually the hit collider.

[Vrixyz]

@AntonPieper Is that still an issue for you with the information provided by Aceeri ?

[AntonPieper]

I have moved on since then and haven't yet started another project again using bevy, so I don't know.

I can check this again this weekend though. Thanks for the valuable information!