bevy/examples/window/multiple_windows.rs
UkoeHB c2c19e5ae4
Text rework (#15591)
**Ready for review. Examples migration progress: 100%.**

# Objective

- Implement https://github.com/bevyengine/bevy/discussions/15014

## Solution

This implements [cart's
proposal](https://github.com/bevyengine/bevy/discussions/15014#discussioncomment-10574459)
faithfully except for one change. I separated `TextSpan` from
`TextSpan2d` because `TextSpan` needs to require the `GhostNode`
component, which is a `bevy_ui` component only usable by UI.

Extra changes:
- Added `EntityCommands::commands_mut` that returns a mutable reference.
This is a blocker for extension methods that return something other than
`self`. Note that `sickle_ui`'s `UiBuilder::commands` returns a mutable
reference for this reason.

## Testing

- [x] Text examples all work.

---

## Showcase

TODO: showcase-worthy

## Migration Guide

TODO: very breaking

### Accessing text spans by index

Text sections are now text sections on different entities in a
hierarchy, Use the new `TextReader` and `TextWriter` system parameters
to access spans by index.

Before:
```rust
fn refresh_text(mut query: Query<&mut Text, With<TimeText>>, time: Res<Time>) {
    let text = query.single_mut();
    text.sections[1].value = format_time(time.elapsed());
}
```

After:
```rust
fn refresh_text(
    query: Query<Entity, With<TimeText>>,
    mut writer: UiTextWriter,
    time: Res<Time>
) {
    let entity = query.single();
    *writer.text(entity, 1) = format_time(time.elapsed());
}
```

### Iterating text spans

Text spans are now entities in a hierarchy, so the new `UiTextReader`
and `UiTextWriter` system parameters provide ways to iterate that
hierarchy. The `UiTextReader::iter` method will give you a normal
iterator over spans, and `UiTextWriter::for_each` lets you visit each of
the spans.

---------

Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2024-10-09 18:35:36 +00:00

57 lines
1.8 KiB
Rust

//! Uses two windows to visualize a 3D model from different angles.
use bevy::{prelude::*, render::camera::RenderTarget, window::WindowRef};
fn main() {
App::new()
// By default, a primary window gets spawned by `WindowPlugin`, contained in `DefaultPlugins`
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup_scene)
.run();
}
fn setup_scene(mut commands: Commands, asset_server: Res<AssetServer>) {
// add entities to the world
commands.spawn(SceneRoot(
asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/torus/torus.gltf")),
));
// light
commands.spawn((
DirectionalLight::default(),
Transform::from_xyz(3.0, 3.0, 3.0).looking_at(Vec3::ZERO, Vec3::Y),
));
let first_window_camera = commands
.spawn((
Camera3d::default(),
Transform::from_xyz(0.0, 0.0, 6.0).looking_at(Vec3::ZERO, Vec3::Y),
))
.id();
// Spawn a second window
let second_window = commands
.spawn(Window {
title: "Second window".to_owned(),
..default()
})
.id();
let second_window_camera = commands
.spawn((
Camera3d::default(),
Transform::from_xyz(6.0, 0.0, 0.0).looking_at(Vec3::ZERO, Vec3::Y),
Camera {
target: RenderTarget::Window(WindowRef::Entity(second_window)),
..default()
},
))
.id();
// Since we are using multiple cameras, we need to specify which camera UI should be rendered to
commands
.spawn((NodeBundle::default(), TargetCamera(first_window_camera)))
.with_child(Text::new("First window"));
commands
.spawn((NodeBundle::default(), TargetCamera(second_window_camera)))
.with_child(Text::new("Second window"));
}