bevy/examples/2d/2d_gizmos.rs
Connor King ab300d0ed9
Gizmo Arrows (#10550)
## Objective

- Add an arrow gizmo as suggested by #9400 

## Solution

(excuse my Protomen music)


https://github.com/bevyengine/bevy/assets/14184826/192adf24-079f-4a4b-a17b-091e892974ec

Wasn't horribly hard when i remembered i can change coordinate systems
whenever I want. Gave them four tips (as suggested by @alice-i-cecile in
discord) instead of trying to decide what direction the tips should
point.

Made the tip length default to 1/10 of the arrow's length, which looked
good enough to me. Hard-coded the angle from the body to the tips to 45
degrees.

## Still TODO

- [x] actual doc comments
- [x] doctests
- [x] `ArrowBuilder.with_tip_length()`

---

## Changelog

- Added `gizmos.arrow()` and `gizmos.arrow_2d()`
- Added arrows to `2d_gizmos` and `3d_gizmos` examples

## Migration Guide

N/A

---------

Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-11-15 14:19:15 +00:00

71 lines
2.1 KiB
Rust

//! This example demonstrates Bevy's immediate mode drawing API intended for visual debugging.
use std::f32::consts::PI;
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, (system, update_config))
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2dBundle::default());
// text
commands.spawn(TextBundle::from_section(
"Hold 'Left' or 'Right' to change the line width",
TextStyle {
font: asset_server.load("fonts/FiraMono-Medium.ttf"),
font_size: 24.,
color: Color::WHITE,
},
));
}
fn system(mut gizmos: Gizmos, time: Res<Time>) {
let sin = time.elapsed_seconds().sin() * 50.;
gizmos.line_2d(Vec2::Y * -sin, Vec2::splat(-80.), Color::RED);
gizmos.ray_2d(Vec2::Y * sin, Vec2::splat(80.), Color::GREEN);
// Triangle
gizmos.linestrip_gradient_2d([
(Vec2::Y * 300., Color::BLUE),
(Vec2::new(-255., -155.), Color::RED),
(Vec2::new(255., -155.), Color::GREEN),
(Vec2::Y * 300., Color::BLUE),
]);
gizmos.rect_2d(
Vec2::ZERO,
time.elapsed_seconds() / 3.,
Vec2::splat(300.),
Color::BLACK,
);
// The circles have 32 line-segments by default.
gizmos.circle_2d(Vec2::ZERO, 120., Color::BLACK);
// You may want to increase this for larger circles.
gizmos.circle_2d(Vec2::ZERO, 300., Color::NAVY).segments(64);
// Arcs default amount of segments is linearly interpolated between
// 1 and 32, using the arc length as scalar.
gizmos.arc_2d(Vec2::ZERO, sin / 10., PI / 2., 350., Color::ORANGE_RED);
gizmos.arrow_2d(
Vec2::ZERO,
Vec2::from_angle(sin / -10. + PI / 2.) * 50.,
Color::YELLOW,
);
}
fn update_config(mut config: ResMut<GizmoConfig>, keyboard: Res<Input<KeyCode>>, time: Res<Time>) {
if keyboard.pressed(KeyCode::Right) {
config.line_width += 5. * time.delta_seconds();
}
if keyboard.pressed(KeyCode::Left) {
config.line_width -= 5. * time.delta_seconds();
}
}