1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
//! This example demonstrates text wrapping and use of the `LineBreakOn` property.

use argh::FromArgs;
use bevy::prelude::*;
use bevy::text::BreakLineOn;
use bevy::window::WindowResolution;
use bevy::winit::WinitSettings;

#[derive(FromArgs, Resource)]
/// `text_wrap_debug` demonstrates text wrapping and use of the `LineBreakOn` property
struct Args {
    #[argh(option)]
    /// window scale factor
    scale_factor: Option<f32>,

    #[argh(option, default = "1.")]
    /// ui scale factor
    ui_scale: f32,
}

fn main() {
    // `from_env` panics on the web
    #[cfg(not(target_arch = "wasm32"))]
    let args: Args = argh::from_env();
    #[cfg(target_arch = "wasm32")]
    let args = Args::from_args(&[], &[]).unwrap();

    let window = if let Some(scale_factor) = args.scale_factor {
        Window {
            resolution: WindowResolution::default().with_scale_factor_override(scale_factor),
            ..Default::default()
        }
    } else {
        Window::default()
    };

    App::new()
        .add_plugins(DefaultPlugins.set(WindowPlugin {
            primary_window: Some(window),
            ..Default::default()
        }))
        .insert_resource(WinitSettings::desktop_app())
        .insert_resource(UiScale(args.ui_scale))
        .add_systems(Startup, spawn)
        .run();
}

fn spawn(mut commands: Commands, asset_server: Res<AssetServer>) {
    commands.spawn(Camera2dBundle::default());

    let text_style = TextStyle {
        font: asset_server.load("fonts/FiraSans-Bold.ttf"),
        font_size: 14.0,
        ..default()
    };

    let root = commands
        .spawn(NodeBundle {
            style: Style {
                width: Val::Percent(100.),
                height: Val::Percent(100.),
                flex_direction: FlexDirection::Column,
                ..Default::default()
            },
            background_color: Color::BLACK.into(),
            ..Default::default()
        })
        .id();

    for linebreak_behavior in [
        BreakLineOn::AnyCharacter,
        BreakLineOn::WordBoundary,
        BreakLineOn::NoWrap,
    ] {
        let row_id = commands
            .spawn(NodeBundle {
                style: Style {
                    flex_direction: FlexDirection::Row,
                    justify_content: JustifyContent::SpaceAround,
                    align_items: AlignItems::Center,
                    width: Val::Percent(100.),
                    height: Val::Percent(50.),
                    ..Default::default()
                },
                ..Default::default()
            })
            .id();

        let justifications = vec![
            JustifyContent::Center,
            JustifyContent::FlexStart,
            JustifyContent::FlexEnd,
            JustifyContent::SpaceAround,
            JustifyContent::SpaceBetween,
            JustifyContent::SpaceEvenly,
        ];

        for (i, justification) in justifications.into_iter().enumerate() {
            let c = 0.3 + i as f32 * 0.1;
            let column_id = commands
                .spawn(NodeBundle {
                    style: Style {
                        justify_content: justification,
                        flex_direction: FlexDirection::Column,
                        width: Val::Percent(16.),
                        height: Val::Percent(95.),
                        overflow: Overflow::clip_x(),
                        ..Default::default()
                    },
                    background_color: Color::srgb(0.5, c, 1.0 - c).into(),
                    ..Default::default()
                })
                .id();

            let messages = [
                format!("JustifyContent::{justification:?}"),
                format!("LineBreakOn::{linebreak_behavior:?}"),
                "Line 1\nLine 2\nLine 3".to_string(),
                "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas auctor, nunc ac faucibus fringilla.".to_string(),
            ];

            for (j, message) in messages.into_iter().enumerate() {
                let text = Text {
                    sections: vec![TextSection {
                        value: message.clone(),
                        style: text_style.clone(),
                    }],
                    justify: JustifyText::Left,
                    linebreak_behavior,
                };
                let text_id = commands
                    .spawn(TextBundle {
                        text,
                        background_color: Color::srgb(0.8 - j as f32 * 0.2, 0., 0.).into(),
                        ..Default::default()
                    })
                    .id();
                commands.entity(column_id).add_child(text_id);
            }
            commands.entity(row_id).add_child(column_id);
        }
        commands.entity(root).add_child(row_id);
    }
}