Bevy 0.13 adding Aabb to Text2d

many_texts.rs

//! Renders a lot of `Text2dBundle`s and adds `Aabb`s so they get automatically culled when out of view.

use bevy::{
    diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
    math::Vec3A,
    prelude::*,
    render::primitives::Aabb,
    text::TextLayoutInfo,
};

use rand::Rng;

const CAMERA_SPEED: f32 = 1000.0;

fn main() {
    App::new()
        .add_plugins((
            FrameTimeDiagnosticsPlugin,
            LogDiagnosticsPlugin::default(),
            DefaultPlugins,
        ))
        .add_systems(Startup, setup)
        .add_systems(
            Update,
            (
                update_text_aabb,
                print_sprite_count,
                move_camera.after(print_sprite_count),
            ),
        )
        .run();
}

fn setup(mut commands: Commands) {
    let mut rng = rand::thread_rng();

    let tile_size = Vec2::splat(64.0);
    let map_size = Vec2::splat(320.0);

    let half_x = (map_size.x / 4.0) as i32;
    let half_y = (map_size.y / 4.0) as i32;

    // Spawns the camera

    commands.spawn(Camera2dBundle::default());

    let text_style = TextStyle {
        font_size: 60.0,
        color: Color::WHITE,
        ..default()
    };

    // Builds and spawns the sprites
    let mut sprites = vec![];
    for y in -half_y..half_y {
        for x in -half_x..half_x {
            let position = Vec2::new(x as f32, y as f32);
            let translation = (position * tile_size).extend(rng.gen::<f32>());
            let rotation = Quat::from_rotation_z(rng.gen::<f32>());
            let scale = Vec3::splat(rng.gen::<f32>() * 2.0);

            sprites.push(Text2dBundle {
                text: Text::from_section("test", text_style.clone()),
                transform: Transform {
                    translation,
                    rotation,
                    scale,
                },
                ..default()
            });
        }
    }
    commands.spawn_batch(sprites);
}

// System for rotating and translating the camera
fn move_camera(time: Res<Time>, mut camera_query: Query<&mut Transform, With<Camera>>) {
    let mut camera_transform = camera_query.single_mut();
    camera_transform.rotate_z(time.delta_seconds() * 0.5);
    *camera_transform = *camera_transform
        * Transform::from_translation(Vec3::X * CAMERA_SPEED * time.delta_seconds());
}

#[derive(Deref, DerefMut)]
struct PrintingTimer(Timer);

impl Default for PrintingTimer {
    fn default() -> Self {
        Self(Timer::from_seconds(1.0, TimerMode::Repeating))
    }
}

// System for printing the number of texts on every tick of the timer
fn print_sprite_count(
    time: Res<Time>,
    mut timer: Local<PrintingTimer>,
    texts: Query<&ViewVisibility, With<Text>>,
) {
    timer.tick(time.delta());

    if timer.just_finished() {
        let visible_texts = texts.iter().filter(|visibility| visibility.get()).count();

        info!("Texts: {} Visible: {}", texts.iter().count(), visible_texts);
    }
}

fn update_text_aabb(
    mut commands: Commands,
    query: Query<(Entity, &TextLayoutInfo), Changed<TextLayoutInfo>>,
) {
    for (entity, info) in query.iter() {
        commands.entity(entity).insert(Aabb {
            center: Vec3A::ZERO,
            half_extents: (info.logical_size / 2.).extend(0.).into(),
        });
    }
}