fog.rs:
use bevy::{
pbr::{NotShadowCaster, NotShadowReceiver},
prelude::*,
};
fn main() {
App::new()
.insert_resource(AmbientLight::NONE)
.add_plugins(DefaultPlugins)
.add_systems(
Startup,
(setup_camera_fog, setup_pyramid_scene, setup_instructions),
)
.add_systems(Update, update_system)
.run();
}
fn setup_camera_fog(mut commands: Commands) {
commands.spawn((
Camera3dBundle::default(),
FogSettings {
color: Color::srgb(0.25, 0.25, 0.25),
falloff: FogFalloff::Linear {
start: 5.0,
end: 20.0,
},
..default()
},
));
}
fn setup_pyramid_scene(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
let stone = materials.add(StandardMaterial {
base_color: Srgba::hex("28221B").unwrap().into(),
perceptual_roughness: 1.0,
..default()
});
for (x, z) in &[(-1.5, -1.5), (1.5, -1.5), (1.5, 1.5), (-1.5, 1.5)] {
commands.spawn(PbrBundle {
mesh: meshes.add(Cuboid::new(1.0, 3.0, 1.0)),
material: stone.clone(),
transform: Transform::from_xyz(*x, 1.5, *z),
..default()
});
}
commands.spawn((
PbrBundle {
mesh: meshes.add(Sphere::default()),
material: materials.add(StandardMaterial {
base_color: Srgba::hex("126212CC").unwrap().into(),
reflectance: 1.0,
perceptual_roughness: 0.0,
metallic: 0.5,
alpha_mode: AlphaMode::Blend,
..default()
}),
transform: Transform::from_scale(Vec3::splat(1.75))
.with_translation(Vec3::new(0.0, 4.0, 0.0)),
..default()
},
NotShadowCaster,
NotShadowReceiver,
));
for i in 0..50 {
let half_size = i as f32 / 2.0 + 3.0;
let y = -i as f32 / 2.0;
commands.spawn(PbrBundle {
mesh: meshes.add(Cuboid::new(2.0 * half_size, 0.5, 2.0 * half_size)),
material: stone.clone(),
transform: Transform::from_xyz(0.0, y + 0.25, 0.0),
..default()
});
}
commands.spawn(PbrBundle {
mesh: meshes.add(Cuboid::new(2.0, 1.0, 1.0)),
material: materials.add(StandardMaterial {
base_color: Srgba::hex("888888").unwrap().into(),
unlit: true,
cull_mode: None,
..default()
}),
transform: Transform::from_scale(Vec3::splat(1_000_000.0)),
..default()
});
commands.spawn(PointLightBundle {
transform: Transform::from_xyz(0.0, 1.0, 0.0),
point_light: PointLight {
shadows_enabled: true,
..default()
},
..default()
});
}
fn setup_instructions(mut commands: Commands) {
commands.spawn(
TextBundle::from_section("", TextStyle::default()).with_style(Style {
position_type: PositionType::Absolute,
top: Val::Px(12.0),
left: Val::Px(12.0),
..default()
}),
);
}
fn update_system(
mut camera: Query<(&mut FogSettings, &mut Transform)>,
mut text: Query<&mut Text>,
time: Res<Time>,
keycode: Res<ButtonInput<KeyCode>>,
) {
let now = time.elapsed_seconds();
let delta = time.delta_seconds();
let (mut fog, mut transform) = camera.single_mut();
let mut text = text.single_mut();
let orbit_scale = 8.0 + (now / 10.0).sin() * 7.0;
*transform = Transform::from_xyz(
(now / 5.0).cos() * orbit_scale,
12.0 - orbit_scale / 2.0,
(now / 5.0).sin() * orbit_scale,
)
.looking_at(Vec3::ZERO, Vec3::Y);
text.sections[0].value = format!("Fog Falloff: {:?}\nFog Color: {:?}", fog.falloff, fog.color);
text.sections[0]
.value
.push_str("\n\n1 / 2 / 3 - Fog Falloff Mode");
if keycode.pressed(KeyCode::Digit1) {
if let FogFalloff::Linear { .. } = fog.falloff {
} else {
fog.falloff = FogFalloff::Linear {
start: 5.0,
end: 20.0,
};
};
}
if keycode.pressed(KeyCode::Digit2) {
if let FogFalloff::Exponential { .. } = fog.falloff {
} else if let FogFalloff::ExponentialSquared { density } = fog.falloff {
fog.falloff = FogFalloff::Exponential { density };
} else {
fog.falloff = FogFalloff::Exponential { density: 0.07 };
};
}
if keycode.pressed(KeyCode::Digit3) {
if let FogFalloff::Exponential { density } = fog.falloff {
fog.falloff = FogFalloff::ExponentialSquared { density };
} else if let FogFalloff::ExponentialSquared { .. } = fog.falloff {
} else {
fog.falloff = FogFalloff::Exponential { density: 0.07 };
};
}
if let FogFalloff::Linear {
ref mut start,
ref mut end,
} = &mut fog.falloff
{
text.sections[0]
.value
.push_str("\nA / S - Move Start Distance\nZ / X - Move End Distance");
if keycode.pressed(KeyCode::KeyA) {
*start -= delta * 3.0;
}
if keycode.pressed(KeyCode::KeyS) {
*start += delta * 3.0;
}
if keycode.pressed(KeyCode::KeyZ) {
*end -= delta * 3.0;
}
if keycode.pressed(KeyCode::KeyX) {
*end += delta * 3.0;
}
}
if let FogFalloff::Exponential { ref mut density } = &mut fog.falloff {
text.sections[0].value.push_str("\nA / S - Change Density");
if keycode.pressed(KeyCode::KeyA) {
*density -= delta * 0.5 * *density;
if *density < 0.0 {
*density = 0.0;
}
}
if keycode.pressed(KeyCode::KeyS) {
*density += delta * 0.5 * *density;
}
}
if let FogFalloff::ExponentialSquared { ref mut density } = &mut fog.falloff {
text.sections[0].value.push_str("\nA / S - Change Density");
if keycode.pressed(KeyCode::KeyA) {
*density -= delta * 0.5 * *density;
if *density < 0.0 {
*density = 0.0;
}
}
if keycode.pressed(KeyCode::KeyS) {
*density += delta * 0.5 * *density;
}
}
text.sections[0]
.value
.push_str("\n\n- / = - Red\n[ / ] - Green\n; / ' - Blue\n. / ? - Alpha");
let mut fog_color = Srgba::from(fog.color);
if keycode.pressed(KeyCode::Minus) {
fog_color.red = (fog_color.red - 0.1 * delta).max(0.0);
}
if keycode.any_pressed([KeyCode::Equal, KeyCode::NumpadEqual]) {
fog_color.red = (fog_color.red + 0.1 * delta).min(1.0);
}
if keycode.pressed(KeyCode::BracketLeft) {
fog_color.green = (fog_color.green - 0.1 * delta).max(0.0);
}
if keycode.pressed(KeyCode::BracketRight) {
fog_color.green = (fog_color.green + 0.1 * delta).min(1.0);
}
if keycode.pressed(KeyCode::Semicolon) {
fog_color.blue = (fog_color.blue - 0.1 * delta).max(0.0);
}
if keycode.pressed(KeyCode::Quote) {
fog_color.blue = (fog_color.blue + 0.1 * delta).min(1.0);
}
if keycode.pressed(KeyCode::Period) {
fog_color.alpha = (fog_color.alpha - 0.1 * delta).max(0.0);
}
if keycode.pressed(KeyCode::Slash) {
fog_color.alpha = (fog_color.alpha + 0.1 * delta).min(1.0);
}
fog.color = Color::from(fog_color);
}