bevy/examples/stress_tests/many_glyphs.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

96 lines
2.8 KiB
Rust

//! Simple text rendering benchmark.
//!
//! Creates a text block with a single span containing `100_000` glyphs,
//! and renders it with the UI in a white color and with Text2d in a red color.
//!
//! To recompute all text each frame run
//! `cargo run --example many_glyphs --release recompute-text`
use bevy::{
color::palettes::basic::RED,
diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
prelude::*,
text::{LineBreak, TextBounds},
window::{PresentMode, WindowResolution},
winit::{UpdateMode, WinitSettings},
};
fn main() {
let mut app = App::new();
app.add_plugins((
DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
present_mode: PresentMode::AutoNoVsync,
resolution: WindowResolution::new(1920.0, 1080.0).with_scale_factor_override(1.0),
..default()
}),
..default()
}),
FrameTimeDiagnosticsPlugin,
LogDiagnosticsPlugin::default(),
))
.insert_resource(WinitSettings {
focused_mode: UpdateMode::Continuous,
unfocused_mode: UpdateMode::Continuous,
})
.add_systems(Startup, setup);
if std::env::args().any(|arg| arg == "recompute-text") {
app.add_systems(Update, force_text_recomputation);
}
app.run();
}
fn setup(mut commands: Commands) {
warn!(include_str!("warning_string.txt"));
commands.spawn(Camera2d);
let text_string = "0123456789".repeat(10_000);
let text_style = TextStyle {
font_size: 4.,
..Default::default()
};
let text_block = TextBlock {
justify: JustifyText::Left,
linebreak: LineBreak::AnyCharacter,
};
commands
.spawn(NodeBundle {
style: Style {
width: Val::Percent(100.),
align_items: AlignItems::Center,
justify_content: JustifyContent::Center,
..default()
},
..default()
})
.with_children(|commands| {
commands
.spawn(NodeBundle {
style: Style {
width: Val::Px(1000.),
..Default::default()
},
..Default::default()
})
.with_child((Text(text_string.clone()), text_style.clone(), text_block));
});
commands.spawn((
Text2d::new(text_string),
TextStyle {
color: RED.into(),
..text_style
},
bevy::sprite::Anchor::Center,
TextBounds::new_horizontal(1000.),
text_block,
));
}
fn force_text_recomputation(mut text_query: Query<&mut TextBlock>) {
for mut block in &mut text_query {
block.set_changed();
}
}