text_wrap_debug/
text_wrap_debug.rs

1//! This example demonstrates text wrapping and use of the `LineBreakOn` property.
2
3use argh::FromArgs;
4use bevy::{prelude::*, text::LineBreak, window::WindowResolution, winit::WinitSettings};
5
6#[derive(FromArgs, Resource)]
7/// `text_wrap_debug` demonstrates text wrapping and use of the `LineBreakOn` property
8struct Args {
9    #[argh(option)]
10    /// window scale factor
11    scale_factor: Option<f32>,
12
13    #[argh(option, default = "1.")]
14    /// ui scale factor
15    ui_scale: f32,
16}
17
18fn main() {
19    // `from_env` panics on the web
20    #[cfg(not(target_arch = "wasm32"))]
21    let args: Args = argh::from_env();
22    #[cfg(target_arch = "wasm32")]
23    let args = Args::from_args(&[], &[]).unwrap();
24
25    let window = if let Some(scale_factor) = args.scale_factor {
26        Window {
27            resolution: WindowResolution::default().with_scale_factor_override(scale_factor),
28            ..Default::default()
29        }
30    } else {
31        Window::default()
32    };
33
34    App::new()
35        .add_plugins(DefaultPlugins.set(WindowPlugin {
36            primary_window: Some(window),
37            ..Default::default()
38        }))
39        .insert_resource(WinitSettings::desktop_app())
40        .insert_resource(UiScale(args.ui_scale))
41        .add_systems(Startup, spawn)
42        .run();
43}
44
45fn spawn(mut commands: Commands, asset_server: Res<AssetServer>) {
46    commands.spawn(Camera2d);
47
48    let text_font = TextFont {
49        font: asset_server.load("fonts/FiraSans-Bold.ttf"),
50        font_size: 12.0,
51        ..default()
52    };
53
54    let root = commands
55        .spawn((
56            Node {
57                width: Val::Percent(100.),
58                height: Val::Percent(100.),
59                flex_direction: FlexDirection::Column,
60                ..default()
61            },
62            BackgroundColor(Color::BLACK),
63        ))
64        .id();
65
66    for linebreak in [
67        LineBreak::AnyCharacter,
68        LineBreak::WordBoundary,
69        LineBreak::WordOrCharacter,
70        LineBreak::NoWrap,
71    ] {
72        let row_id = commands
73            .spawn(Node {
74                flex_direction: FlexDirection::Row,
75                justify_content: JustifyContent::SpaceAround,
76                align_items: AlignItems::Center,
77                width: Val::Percent(100.),
78                height: Val::Percent(50.),
79                ..default()
80            })
81            .id();
82
83        let justifications = vec![
84            JustifyContent::Center,
85            JustifyContent::FlexStart,
86            JustifyContent::FlexEnd,
87            JustifyContent::SpaceAround,
88            JustifyContent::SpaceBetween,
89            JustifyContent::SpaceEvenly,
90        ];
91
92        for (i, justification) in justifications.into_iter().enumerate() {
93            let c = 0.3 + i as f32 * 0.1;
94            let column_id = commands
95                .spawn((
96                    Node {
97                        justify_content: justification,
98                        flex_direction: FlexDirection::Column,
99                        width: Val::Percent(16.),
100                        height: Val::Percent(95.),
101                        overflow: Overflow::clip_x(),
102                        ..default()
103                    },
104                    BackgroundColor(Color::srgb(0.5, c, 1.0 - c)),
105                ))
106                .id();
107
108            let messages = [
109                format!("JustifyContent::{justification:?}"),
110                format!("LineBreakOn::{linebreak:?}"),
111                "Line 1\nLine 2".to_string(),
112                "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas auctor, nunc ac faucibus fringilla.".to_string(),
113                "pneumonoultramicroscopicsilicovolcanoconiosis".to_string()
114            ];
115
116            for (j, message) in messages.into_iter().enumerate() {
117                commands.entity(column_id).with_child((
118                    Text(message.clone()),
119                    text_font.clone(),
120                    TextLayout::new(JustifyText::Left, linebreak),
121                    BackgroundColor(Color::srgb(0.8 - j as f32 * 0.2, 0., 0.)),
122                ));
123            }
124            commands.entity(row_id).add_child(column_id);
125        }
126        commands.entity(root).add_child(row_id);
127    }
128}
text_wrap_debug/text_wrap_debug.rs

text_wrap_debug/
text_wrap_debug.rs
