bevy/examples/3d/3d_viewport_to_world.rs
Arthur Brussee ffb6faafc2
Use Direction3d for gizmos.circle normal (#11422)
# Objective

Fix weird visuals when drawing a gizmo with a non-normed normal.

Fixes #11401

## Solution
Just normalize right before we draw. Could do it when constructing the
builder but that seems less consistent.

## Changelog
- gizmos.circle normal is now a Direction3d instead of a Vec3.

## Migration Guide
- Pass a Direction3d for gizmos.circle normal, eg.
`Direction3d::new(vec).unwrap_or(default)` or potentially
`Direction3d::new_unchecked(vec)` if you know your vec is definitely
normalized.
2024-01-21 18:03:26 +00:00

81 lines
2.2 KiB
Rust

//! This example demonstrates how to use the `Camera::viewport_to_world` method.
use bevy::math::primitives::Direction3d;
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, draw_cursor)
.run();
}
fn draw_cursor(
camera_query: Query<(&Camera, &GlobalTransform)>,
ground_query: Query<&GlobalTransform, With<Ground>>,
windows: Query<&Window>,
mut gizmos: Gizmos,
) {
let (camera, camera_transform) = camera_query.single();
let ground = ground_query.single();
let Some(cursor_position) = windows.single().cursor_position() else {
return;
};
// Calculate a ray pointing from the camera into the world based on the cursor's position.
let Some(ray) = camera.viewport_to_world(camera_transform, cursor_position) else {
return;
};
// Calculate if and where the ray is hitting the ground plane.
let Some(distance) = ray.intersect_plane(ground.translation(), Plane3d::new(ground.up()))
else {
return;
};
let point = ray.get_point(distance);
// Draw a circle just above the ground plane at that position.
gizmos.circle(
point + ground.up() * 0.01,
Direction3d::new_unchecked(ground.up()), // Up vector is already normalized.
0.2,
Color::WHITE,
);
}
#[derive(Component)]
struct Ground;
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
// plane
commands.spawn((
PbrBundle {
mesh: meshes.add(shape::Plane::from_size(20.)),
material: materials.add(Color::rgb(0.3, 0.5, 0.3)),
..default()
},
Ground,
));
// light
commands.spawn(DirectionalLightBundle {
transform: Transform::from_translation(Vec3::ONE).looking_at(Vec3::ZERO, Vec3::Y),
directional_light: DirectionalLight {
illuminance: 2000.0,
..default()
},
..default()
});
// camera
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(15.0, 5.0, 15.0).looking_at(Vec3::ZERO, Vec3::Y),
..default()
});
}