2d_gizmos/
2d_gizmos.rs

1//! This example demonstrates Bevy's immediate mode drawing API intended for visual debugging.
2
3use std::f32::consts::{FRAC_PI_2, PI, TAU};
4
5use bevy::{color::palettes::css::*, math::Isometry2d, prelude::*};
6
7fn main() {
8    App::new()
9        .add_plugins(DefaultPlugins)
10        .init_gizmo_group::<MyRoundGizmos>()
11        .add_systems(Startup, setup)
12        .add_systems(Update, (draw_example_collection, update_config))
13        .run();
14}
15
16// We can create our own gizmo config group!
17#[derive(Default, Reflect, GizmoConfigGroup)]
18struct MyRoundGizmos {}
19
20fn setup(mut commands: Commands) {
21    commands.spawn(Camera2d);
22    // text
23    commands.spawn((
24        Text::new(
25            "Hold 'Left' or 'Right' to change the line width of straight gizmos\n\
26        Hold 'Up' or 'Down' to change the line width of round gizmos\n\
27        Press '1' / '2' to toggle the visibility of straight / round gizmos\n\
28        Press 'U' / 'I' to cycle through line styles\n\
29        Press 'J' / 'K' to cycle through line joins\n\
30        Press 'Spacebar' to toggle pause",
31        ),
32        Node {
33            position_type: PositionType::Absolute,
34            top: px(12),
35            left: px(12),
36            ..default()
37        },
38    ));
39}
40
41fn draw_example_collection(
42    mut gizmos: Gizmos,
43    mut my_gizmos: Gizmos<MyRoundGizmos>,
44    time: Res<Time>,
45) {
46    let sin_t_scaled = ops::sin(time.elapsed_secs()) * 50.;
47    gizmos.line_2d(Vec2::Y * -sin_t_scaled, Vec2::splat(-80.), RED);
48    gizmos.ray_2d(Vec2::Y * sin_t_scaled, Vec2::splat(80.), LIME);
49
50    gizmos
51        .grid_2d(
52            Isometry2d::IDENTITY,
53            UVec2::new(16, 9),
54            Vec2::new(80., 80.),
55            // Dark gray
56            LinearRgba::gray(0.05),
57        )
58        .outer_edges();
59
60    // Triangle
61    gizmos.linestrip_gradient_2d([
62        (Vec2::Y * 300., BLUE),
63        (Vec2::new(-255., -155.), RED),
64        (Vec2::new(255., -155.), LIME),
65        (Vec2::Y * 300., BLUE),
66    ]);
67
68    gizmos.rect_2d(Isometry2d::IDENTITY, Vec2::splat(650.), BLACK);
69
70    gizmos.cross_2d(Vec2::new(-160., 120.), 12., FUCHSIA);
71
72    let domain = Interval::EVERYWHERE;
73    let curve = FunctionCurve::new(domain, |t| Vec2::new(t, ops::sin(t / 25.0) * 100.0));
74    let resolution = ((ops::sin(time.elapsed_secs()) + 1.0) * 50.0) as usize;
75    let times_and_colors = (0..=resolution)
76        .map(|n| n as f32 / resolution as f32)
77        .map(|t| (t - 0.5) * 600.0)
78        .map(|t| (t, TEAL.mix(&HOT_PINK, (t + 300.0) / 600.0)));
79    gizmos.curve_gradient_2d(curve, times_and_colors);
80
81    my_gizmos
82        .rounded_rect_2d(Isometry2d::IDENTITY, Vec2::splat(630.), BLACK)
83        .corner_radius(ops::cos(time.elapsed_secs() / 3.) * 100.);
84
85    // Circles have 32 line-segments by default.
86    // You may want to increase this for larger circles.
87    my_gizmos
88        .circle_2d(Isometry2d::IDENTITY, 300., NAVY)
89        .resolution(64);
90
91    my_gizmos.ellipse_2d(
92        Rot2::radians(time.elapsed_secs() % TAU),
93        Vec2::new(100., 200.),
94        YELLOW_GREEN,
95    );
96
97    // Arcs default resolution is linearly interpolated between
98    // 1 and 32, using the arc length as scalar.
99    my_gizmos.arc_2d(
100        Rot2::radians(sin_t_scaled / 10.),
101        FRAC_PI_2,
102        310.,
103        ORANGE_RED,
104    );
105    my_gizmos.arc_2d(Isometry2d::IDENTITY, FRAC_PI_2, 80.0, ORANGE_RED);
106    my_gizmos.long_arc_2d_between(Vec2::ZERO, Vec2::X * 20.0, Vec2::Y * 20.0, ORANGE_RED);
107    my_gizmos.short_arc_2d_between(Vec2::ZERO, Vec2::X * 40.0, Vec2::Y * 40.0, ORANGE_RED);
108
109    gizmos.arrow_2d(
110        Vec2::ZERO,
111        Vec2::from_angle(sin_t_scaled / -10. + PI / 2.) * 50.,
112        YELLOW,
113    );
114
115    // You can create more complex arrows using the arrow builder.
116    gizmos
117        .arrow_2d(
118            Vec2::ZERO,
119            Vec2::from_angle(sin_t_scaled / -10.) * 50.,
120            GREEN,
121        )
122        .with_double_end()
123        .with_tip_length(10.);
124}
125
126fn update_config(
127    mut config_store: ResMut<GizmoConfigStore>,
128    keyboard: Res<ButtonInput<KeyCode>>,
129    real_time: Res<Time<Real>>,
130    mut virtual_time: ResMut<Time<Virtual>>,
131) {
132    let (config, _) = config_store.config_mut::<DefaultGizmoConfigGroup>();
133    if keyboard.pressed(KeyCode::ArrowRight) {
134        config.line.width += 5. * real_time.delta_secs();
135        config.line.width = config.line.width.clamp(0., 50.);
136    }
137    if keyboard.pressed(KeyCode::ArrowLeft) {
138        config.line.width -= 5. * real_time.delta_secs();
139        config.line.width = config.line.width.clamp(0., 50.);
140    }
141    if keyboard.just_pressed(KeyCode::Digit1) {
142        config.enabled ^= true;
143    }
144    if keyboard.just_pressed(KeyCode::KeyU) {
145        config.line.style = match config.line.style {
146            GizmoLineStyle::Solid => GizmoLineStyle::Dotted,
147            GizmoLineStyle::Dotted => GizmoLineStyle::Dashed {
148                gap_scale: 3.0,
149                line_scale: 5.0,
150            },
151            _ => GizmoLineStyle::Solid,
152        };
153    }
154    if keyboard.just_pressed(KeyCode::KeyI) {
155        config.line.style = match config.line.style {
156            GizmoLineStyle::Solid => GizmoLineStyle::Dashed {
157                gap_scale: 3.0,
158                line_scale: 5.0,
159            },
160            GizmoLineStyle::Dotted => GizmoLineStyle::Solid,
161            _ => GizmoLineStyle::Dotted,
162        };
163    }
164    if keyboard.just_pressed(KeyCode::KeyJ) {
165        config.line.joints = match config.line.joints {
166            GizmoLineJoint::Bevel => GizmoLineJoint::Miter,
167            GizmoLineJoint::Miter => GizmoLineJoint::Round(4),
168            GizmoLineJoint::Round(_) => GizmoLineJoint::None,
169            GizmoLineJoint::None => GizmoLineJoint::Bevel,
170        };
171    }
172
173    if keyboard.just_pressed(KeyCode::KeyK) {
174        config.line.joints = match config.line.joints {
175            GizmoLineJoint::Bevel => GizmoLineJoint::None,
176            GizmoLineJoint::Miter => GizmoLineJoint::Bevel,
177            GizmoLineJoint::Round(_) => GizmoLineJoint::Miter,
178            GizmoLineJoint::None => GizmoLineJoint::Round(4),
179        };
180    }
181
182    let (my_config, _) = config_store.config_mut::<MyRoundGizmos>();
183    if keyboard.pressed(KeyCode::ArrowUp) {
184        my_config.line.width += 5. * real_time.delta_secs();
185        my_config.line.width = my_config.line.width.clamp(0., 50.);
186    }
187    if keyboard.pressed(KeyCode::ArrowDown) {
188        my_config.line.width -= 5. * real_time.delta_secs();
189        my_config.line.width = my_config.line.width.clamp(0., 50.);
190    }
191    if keyboard.just_pressed(KeyCode::Digit2) {
192        my_config.enabled ^= true;
193    }
194    if keyboard.just_pressed(KeyCode::KeyI) {
195        my_config.line.style = match my_config.line.style {
196            GizmoLineStyle::Solid => GizmoLineStyle::Dotted,
197            GizmoLineStyle::Dotted => GizmoLineStyle::Dashed {
198                gap_scale: 3.0,
199                line_scale: 5.0,
200            },
201            _ => GizmoLineStyle::Solid,
202        };
203    }
204    if keyboard.just_pressed(KeyCode::KeyK) {
205        my_config.line.joints = match my_config.line.joints {
206            GizmoLineJoint::Bevel => GizmoLineJoint::Miter,
207            GizmoLineJoint::Miter => GizmoLineJoint::Round(4),
208            GizmoLineJoint::Round(_) => GizmoLineJoint::None,
209            GizmoLineJoint::None => GizmoLineJoint::Bevel,
210        };
211    }
212    if keyboard.just_pressed(KeyCode::Space) {
213        virtual_time.toggle();
214    }
215}
2d_gizmos/2d_gizmos.rs

2d_gizmos/
2d_gizmos.rs
