bevy/examples/picking/simple_picking.rs
ickshonpe 6f7d0e5725
split up TextStyle (#15857)
# Objective

Currently text is recomputed unnecessarily on any changes to its color,
which is extremely expensive.

## Solution
Split up `TextStyle` into two separate components `TextFont` and
`TextColor`.

## Testing

I added this system to `many_buttons`:
```rust
fn set_text_colors_changed(mut colors: Query<&mut TextColor>) {
    for mut text_color in colors.iter_mut() {
        text_color.set_changed();
    }
}
```

reports ~4fps on main, ~50fps with this PR.

## Migration Guide
`TextStyle` has been renamed to `TextFont` and its `color` field has
been moved to a separate component named `TextColor` which newtypes
`Color`.
2024-10-13 17:06:22 +00:00

75 lines
2.3 KiB
Rust

//! A simple scene to demonstrate picking events
use bevy::{color::palettes::tailwind::CYAN_400, prelude::*};
fn main() {
let mut app = App::new();
app.add_plugins(DefaultPlugins);
app.add_systems(Startup, setup);
app.run();
}
/// set up a simple 3D scene
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
commands
.spawn((
Text::new("Click Me to get a box"),
Style {
position_type: PositionType::Absolute,
top: Val::Percent(12.0),
left: Val::Percent(12.0),
..default()
},
))
.observe(
|_click: Trigger<Pointer<Click>>,
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
mut num: Local<usize>| {
commands.spawn((
Mesh3d(meshes.add(Cuboid::new(1.0, 1.0, 1.0))),
MeshMaterial3d(materials.add(Color::srgb_u8(124, 144, 255))),
Transform::from_xyz(0.0, 0.5 + 1.1 * *num as f32, 0.0),
));
*num += 1;
},
)
.observe(
|evt: Trigger<Pointer<Out>>, mut texts: Query<&mut TextColor>| {
let mut color = texts.get_mut(evt.entity()).unwrap();
color.0 = Color::WHITE;
},
)
.observe(
|evt: Trigger<Pointer<Over>>, mut texts: Query<&mut TextColor>| {
let mut color = texts.get_mut(evt.entity()).unwrap();
color.0 = CYAN_400.into();
},
);
// circular base
commands.spawn((
Mesh3d(meshes.add(Circle::new(4.0))),
MeshMaterial3d(materials.add(Color::WHITE)),
Transform::from_rotation(Quat::from_rotation_x(-std::f32::consts::FRAC_PI_2)),
));
// light
commands.spawn((
PointLight {
shadows_enabled: true,
..default()
},
Transform::from_xyz(4.0, 8.0, 4.0),
));
// camera
commands.spawn((
Camera3d::default(),
Transform::from_xyz(-2.5, 4.5, 9.0).looking_at(Vec3::ZERO, Vec3::Y),
));
}