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(
13            Update,
14            (
15                draw_example_collection,
16                update_config,
17                drive_gizmos_animation,
18            ),
19        )
20        .run();
21}
22
23// We can create our own gizmo config group!
24#[derive(Default, Reflect, GizmoConfigGroup)]
25struct MyRoundGizmos {}
26
27fn setup(mut commands: Commands) {
28    commands.spawn(Camera2d);
29    // text
30    commands.spawn((
31        Text::new(
32            "Hold 'Left' or 'Right' to change the line width of straight gizmos\n\
33        Hold 'Up' or 'Down' to change the line width of round gizmos\n\
34        Press '1' / '2' to toggle the visibility of straight / round gizmos\n\
35        Press 'U' / 'I' to cycle through line styles\n\
36        Press 'J' / 'K' to cycle through line joins\n\
37        Press 'L' to cycle through gizmos animations (only for dotted/dashed round gizmos)\n\
38        Press 'Spacebar' to toggle pause",
39        ),
40        Node {
41            position_type: PositionType::Absolute,
42            top: px(12),
43            left: px(12),
44            ..default()
45        },
46    ));
47}
48
49fn draw_example_collection(
50    mut gizmos: Gizmos,
51    mut my_gizmos: Gizmos<MyRoundGizmos>,
52    time: Res<Time>,
53) {
54    let sin_t_scaled = ops::sin(time.elapsed_secs()) * 50.;
55    gizmos.line_2d(Vec2::Y * -sin_t_scaled, Vec2::splat(-80.), RED);
56    gizmos.ray_2d(Vec2::Y * sin_t_scaled, Vec2::splat(80.), LIME);
57
58    gizmos
59        .grid_2d(
60            Isometry2d::IDENTITY,
61            UVec2::new(16, 9),
62            Vec2::new(80., 80.),
63            // Dark gray
64            LinearRgba::gray(0.05),
65        )
66        .outer_edges();
67
68    // Triangle
69    gizmos.linestrip_gradient_2d([
70        (Vec2::Y * 300., BLUE),
71        (Vec2::new(-255., -155.), RED),
72        (Vec2::new(255., -155.), LIME),
73        (Vec2::Y * 300., BLUE),
74    ]);
75
76    gizmos.rect_2d(Isometry2d::IDENTITY, Vec2::splat(650.), BLACK);
77
78    gizmos.cross_2d(Vec2::new(-160., 120.), 12., FUCHSIA);
79
80    let domain = Interval::EVERYWHERE;
81    let curve = FunctionCurve::new(domain, |t| Vec2::new(t, ops::sin(t / 25.0) * 100.0));
82    let resolution = ((ops::sin(time.elapsed_secs()) + 1.0) * 50.0) as usize;
83    let times_and_colors = (0..=resolution)
84        .map(|n| n as f32 / resolution as f32)
85        .map(|t| (t - 0.5) * 600.0)
86        .map(|t| (t, TEAL.mix(&HOT_PINK, (t + 300.0) / 600.0)));
87    gizmos.curve_gradient_2d(curve, times_and_colors);
88
89    my_gizmos
90        .rounded_rect_2d(Isometry2d::IDENTITY, Vec2::splat(630.), BLACK)
91        .corner_radius(ops::cos(time.elapsed_secs() / 3.) * 100.);
92
93    // Circles have 32 line-segments by default.
94    // You may want to increase this for larger circles.
95    my_gizmos
96        .circle_2d(Isometry2d::IDENTITY, 300., NAVY)
97        .resolution(64);
98
99    my_gizmos.ellipse_2d(
100        Rot2::radians(time.elapsed_secs() % TAU),
101        Vec2::new(100., 200.),
102        YELLOW_GREEN,
103    );
104
105    // Arcs default resolution is linearly interpolated between
106    // 1 and 32, using the arc length as scalar.
107    my_gizmos.arc_2d(
108        Rot2::radians(sin_t_scaled / 10.),
109        FRAC_PI_2,
110        310.,
111        ORANGE_RED,
112    );
113    my_gizmos.arc_2d(Isometry2d::IDENTITY, FRAC_PI_2, 80.0, ORANGE_RED);
114    my_gizmos.long_arc_2d_between(Vec2::ZERO, Vec2::X * 20.0, Vec2::Y * 20.0, ORANGE_RED);
115    my_gizmos.short_arc_2d_between(Vec2::ZERO, Vec2::X * 40.0, Vec2::Y * 40.0, ORANGE_RED);
116
117    gizmos.arrow_2d(
118        Vec2::ZERO,
119        Vec2::from_angle(sin_t_scaled / -10. + PI / 2.) * 50.,
120        YELLOW,
121    );
122
123    // You can create more complex arrows using the arrow builder.
124    gizmos
125        .arrow_2d(
126            Vec2::ZERO,
127            Vec2::from_angle(sin_t_scaled / -10.) * 50.,
128            GREEN,
129        )
130        .with_double_end()
131        .with_tip_length(10.);
132
133    my_gizmos.arc_2d(Isometry2d::default(), FRAC_PI_2, 210., OLD_LACE);
134}
135
136fn update_config(
137    mut config_store: ResMut<GizmoConfigStore>,
138    keyboard: Res<ButtonInput<KeyCode>>,
139    real_time: Res<Time<Real>>,
140    mut virtual_time: ResMut<Time<Virtual>>,
141) {
142    let (config, _) = config_store.config_mut::<DefaultGizmoConfigGroup>();
143    if keyboard.pressed(KeyCode::ArrowRight) {
144        config.line.width += 5. * real_time.delta_secs();
145        config.line.width = config.line.width.clamp(0., 50.);
146    }
147    if keyboard.pressed(KeyCode::ArrowLeft) {
148        config.line.width -= 5. * real_time.delta_secs();
149        config.line.width = config.line.width.clamp(0., 50.);
150    }
151    if keyboard.just_pressed(KeyCode::Digit1) {
152        config.enabled ^= true;
153    }
154    if keyboard.just_pressed(KeyCode::KeyU) {
155        config.line.style = match config.line.style {
156            GizmoLineStyle::Solid => GizmoLineStyle::Dotted,
157            GizmoLineStyle::Dotted => GizmoLineStyle::Dashed {
158                gap_scale: 3.0,
159                line_scale: 5.0,
160            },
161            _ => GizmoLineStyle::Solid,
162        };
163    }
164    if keyboard.just_pressed(KeyCode::KeyI) {
165        config.line.style = match config.line.style {
166            GizmoLineStyle::Solid => GizmoLineStyle::Dashed {
167                gap_scale: 3.0,
168                line_scale: 5.0,
169            },
170            GizmoLineStyle::Dotted => GizmoLineStyle::Solid,
171            _ => GizmoLineStyle::Dotted,
172        };
173    }
174    if keyboard.just_pressed(KeyCode::KeyJ) {
175        config.line.joints = match config.line.joints {
176            GizmoLineJoint::Bevel => GizmoLineJoint::Miter,
177            GizmoLineJoint::Miter => GizmoLineJoint::Round(4),
178            GizmoLineJoint::Round(_) => GizmoLineJoint::None,
179            GizmoLineJoint::None => GizmoLineJoint::Bevel,
180        };
181    }
182
183    if keyboard.just_pressed(KeyCode::KeyK) {
184        config.line.joints = match config.line.joints {
185            GizmoLineJoint::Bevel => GizmoLineJoint::None,
186            GizmoLineJoint::Miter => GizmoLineJoint::Bevel,
187            GizmoLineJoint::Round(_) => GizmoLineJoint::Miter,
188            GizmoLineJoint::None => GizmoLineJoint::Round(4),
189        };
190    }
191
192    let (my_config, _) = config_store.config_mut::<MyRoundGizmos>();
193    if keyboard.pressed(KeyCode::ArrowUp) {
194        my_config.line.width += 5. * real_time.delta_secs();
195        my_config.line.width = my_config.line.width.clamp(0., 50.);
196    }
197    if keyboard.pressed(KeyCode::ArrowDown) {
198        my_config.line.width -= 5. * real_time.delta_secs();
199        my_config.line.width = my_config.line.width.clamp(0., 50.);
200    }
201    if keyboard.just_pressed(KeyCode::Digit2) {
202        my_config.enabled ^= true;
203    }
204    if keyboard.just_pressed(KeyCode::KeyI) {
205        my_config.line.style = match my_config.line.style {
206            GizmoLineStyle::Solid => GizmoLineStyle::Dotted,
207            GizmoLineStyle::Dotted => GizmoLineStyle::Dashed {
208                gap_scale: 3.0,
209                line_scale: 5.0,
210            },
211            _ => GizmoLineStyle::Solid,
212        };
213    }
214    if keyboard.just_pressed(KeyCode::KeyK) {
215        my_config.line.joints = match my_config.line.joints {
216            GizmoLineJoint::Bevel => GizmoLineJoint::Miter,
217            GizmoLineJoint::Miter => GizmoLineJoint::Round(4),
218            GizmoLineJoint::Round(_) => GizmoLineJoint::None,
219            GizmoLineJoint::None => GizmoLineJoint::Bevel,
220        };
221    }
222
223    if keyboard.just_pressed(KeyCode::Space) {
224        virtual_time.toggle();
225    }
226}
227
228enum GizmosAnimationType {
229    Linear,
230    BackAndForth,
231    Stutter,
232}
233
234fn drive_gizmos_animation(
235    mut config_store: ResMut<GizmoConfigStore>,
236    virtual_time: ResMut<Time<Virtual>>,
237    keyboard: Res<ButtonInput<KeyCode>>,
238    mut animation_type: Local<Option<GizmosAnimationType>>,
239) {
240    if keyboard.just_pressed(KeyCode::KeyL) {
241        *animation_type = match *animation_type {
242            None => Some(GizmosAnimationType::Linear),
243            Some(GizmosAnimationType::Linear) => Some(GizmosAnimationType::BackAndForth),
244            Some(GizmosAnimationType::BackAndForth) => Some(GizmosAnimationType::Stutter),
245            Some(GizmosAnimationType::Stutter) => None,
246        };
247    }
248
249    if let Some(animation_type) = animation_type.as_ref() {
250        let (my_config, _) = config_store.config_mut::<MyRoundGizmos>();
251        match animation_type {
252            GizmosAnimationType::Linear => {
253                my_config.line.animation_offset = virtual_time.elapsed_secs() * 10.0;
254            }
255            GizmosAnimationType::BackAndForth => {
256                my_config.line.animation_offset = ops::sin(virtual_time.elapsed_secs()) * 10.0;
257            }
258            GizmosAnimationType::Stutter => {
259                my_config.line.animation_offset = (virtual_time.elapsed_secs() * 4.0).round();
260            }
261        }
262    }
263}
2d_gizmos/2d_gizmos.rs

2d_gizmos/
2d_gizmos.rs
