Support Warning
WebGPU is currently only supported on Chrome starting with version 113, and only on desktop. If they don't work on your configuration, you can check the WebGL2 examples here.parallax_mapping.rs:
//! A simple 3D scene with a spinning cube with a normal map and depth map to demonstrate parallax mapping.
//! Press left mouse button to cycle through different views.
use std::fmt;
use bevy::{prelude::*, render::texture::ImageLoaderSettings};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(
Update,
(
spin,
move_camera,
update_parallax_depth_scale,
update_parallax_layers,
switch_method,
),
)
.run();
}
#[derive(Component)]
struct Spin {
speed: f32,
}
/// The camera, used to move camera on click.
#[derive(Component)]
struct CameraController;
const DEPTH_CHANGE_RATE: f32 = 0.1;
const DEPTH_UPDATE_STEP: f32 = 0.03;
const MAX_DEPTH: f32 = 0.3;
struct TargetDepth(f32);
impl Default for TargetDepth {
fn default() -> Self {
TargetDepth(0.09)
}
}
struct TargetLayers(f32);
impl Default for TargetLayers {
fn default() -> Self {
TargetLayers(5.0)
}
}
struct CurrentMethod(ParallaxMappingMethod);
impl Default for CurrentMethod {
fn default() -> Self {
CurrentMethod(ParallaxMappingMethod::Relief { max_steps: 4 })
}
}
impl fmt::Display for CurrentMethod {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self.0 {
ParallaxMappingMethod::Occlusion => write!(f, "Parallax Occlusion Mapping"),
ParallaxMappingMethod::Relief { max_steps } => {
write!(f, "Relief Mapping with {max_steps} steps")
}
}
}
}
impl CurrentMethod {
fn next_method(&mut self) {
use ParallaxMappingMethod::*;
self.0 = match self.0 {
Occlusion => Relief { max_steps: 2 },
Relief { max_steps } if max_steps < 3 => Relief { max_steps: 4 },
Relief { max_steps } if max_steps < 5 => Relief { max_steps: 8 },
Relief { .. } => Occlusion,
}
}
}
fn update_parallax_depth_scale(
input: Res<ButtonInput<KeyCode>>,
mut materials: ResMut<Assets<StandardMaterial>>,
mut target_depth: Local<TargetDepth>,
mut depth_update: Local<bool>,
mut text: Query<&mut Text>,
) {
if input.just_pressed(KeyCode::Digit1) {
target_depth.0 -= DEPTH_UPDATE_STEP;
target_depth.0 = target_depth.0.max(0.0);
*depth_update = true;
}
if input.just_pressed(KeyCode::Digit2) {
target_depth.0 += DEPTH_UPDATE_STEP;
target_depth.0 = target_depth.0.min(MAX_DEPTH);
*depth_update = true;
}
if *depth_update {
let mut text = text.single_mut();
for (_, mat) in materials.iter_mut() {
let current_depth = mat.parallax_depth_scale;
let new_depth = current_depth.lerp(target_depth.0, DEPTH_CHANGE_RATE);
mat.parallax_depth_scale = new_depth;
text.sections[0].value = format!("Parallax depth scale: {new_depth:.5}\n");
if (new_depth - current_depth).abs() <= 0.000000001 {
*depth_update = false;
}
}
}
}
fn switch_method(
input: Res<ButtonInput<KeyCode>>,
mut materials: ResMut<Assets<StandardMaterial>>,
mut text: Query<&mut Text>,
mut current: Local<CurrentMethod>,
) {
if input.just_pressed(KeyCode::Space) {
current.next_method();
} else {
return;
}
let mut text = text.single_mut();
text.sections[2].value = format!("Method: {}\n", *current);
for (_, mat) in materials.iter_mut() {
mat.parallax_mapping_method = current.0;
}
}
fn update_parallax_layers(
input: Res<ButtonInput<KeyCode>>,
mut materials: ResMut<Assets<StandardMaterial>>,
mut target_layers: Local<TargetLayers>,
mut text: Query<&mut Text>,
) {
if input.just_pressed(KeyCode::Digit3) {
target_layers.0 -= 1.0;
target_layers.0 = target_layers.0.max(0.0);
} else if input.just_pressed(KeyCode::Digit4) {
target_layers.0 += 1.0;
} else {
return;
}
let layer_count = target_layers.0.exp2();
let mut text = text.single_mut();
text.sections[1].value = format!("Layers: {layer_count:.0}\n");
for (_, mat) in materials.iter_mut() {
mat.max_parallax_layer_count = layer_count;
}
}
fn spin(time: Res<Time>, mut query: Query<(&mut Transform, &Spin)>) {
for (mut transform, spin) in query.iter_mut() {
transform.rotate_local_y(spin.speed * time.delta_seconds());
transform.rotate_local_x(spin.speed * time.delta_seconds());
transform.rotate_local_z(-spin.speed * time.delta_seconds());
}
}
// Camera positions to cycle through when left-clicking.
const CAMERA_POSITIONS: &[Transform] = &[
Transform {
translation: Vec3::new(1.5, 1.5, 1.5),
rotation: Quat::from_xyzw(-0.279, 0.364, 0.115, 0.880),
scale: Vec3::ONE,
},
Transform {
translation: Vec3::new(2.4, 0.0, 0.2),
rotation: Quat::from_xyzw(0.094, 0.676, 0.116, 0.721),
scale: Vec3::ONE,
},
Transform {
translation: Vec3::new(2.4, 2.6, -4.3),
rotation: Quat::from_xyzw(0.170, 0.908, 0.308, 0.225),
scale: Vec3::ONE,
},
Transform {
translation: Vec3::new(-1.0, 0.8, -1.2),
rotation: Quat::from_xyzw(-0.004, 0.909, 0.247, -0.335),
scale: Vec3::ONE,
},
];
fn move_camera(
mut camera: Query<&mut Transform, With<CameraController>>,
mut current_view: Local<usize>,
button: Res<ButtonInput<MouseButton>>,
) {
let mut camera = camera.single_mut();
if button.just_pressed(MouseButton::Left) {
*current_view = (*current_view + 1) % CAMERA_POSITIONS.len();
}
let target = CAMERA_POSITIONS[*current_view];
camera.translation = camera.translation.lerp(target.translation, 0.2);
camera.rotation = camera.rotation.slerp(target.rotation, 0.2);
}
fn setup(
mut commands: Commands,
mut materials: ResMut<Assets<StandardMaterial>>,
mut meshes: ResMut<Assets<Mesh>>,
asset_server: Res<AssetServer>,
) {
// The normal map. Note that to generate it in the GIMP image editor, you should
// open the depth map, and do Filters → Generic → Normal Map
// You should enable the "flip X" checkbox.
let normal_handle = asset_server.load_with_settings(
"textures/parallax_example/cube_normal.png",
// The normal map texture is in linear color space. Lighting won't look correct
// if `is_srgb` is `true`, which is the default.
|settings: &mut ImageLoaderSettings| settings.is_srgb = false,
);
// Camera
commands.spawn((
Camera3dBundle {
transform: Transform::from_xyz(1.5, 1.5, 1.5).looking_at(Vec3::ZERO, Vec3::Y),
..default()
},
CameraController,
));
// light
commands
.spawn(PointLightBundle {
transform: Transform::from_xyz(2.0, 1.0, -1.1),
point_light: PointLight {
shadows_enabled: true,
..default()
},
..default()
})
.with_children(|commands| {
// represent the light source as a sphere
let mesh = meshes.add(Sphere::new(0.05).mesh().ico(3).unwrap());
commands.spawn(PbrBundle { mesh, ..default() });
});
// Plane
commands.spawn(PbrBundle {
mesh: meshes.add(Plane3d::default().mesh().size(10.0, 10.0)),
material: materials.add(StandardMaterial {
// standard material derived from dark green, but
// with roughness and reflectance set.
perceptual_roughness: 0.45,
reflectance: 0.18,
..Color::srgb_u8(0, 80, 0).into()
}),
transform: Transform::from_xyz(0.0, -1.0, 0.0),
..default()
});
let parallax_depth_scale = TargetDepth::default().0;
let max_parallax_layer_count = TargetLayers::default().0.exp2();
let parallax_mapping_method = CurrentMethod::default();
let parallax_material = materials.add(StandardMaterial {
perceptual_roughness: 0.4,
base_color_texture: Some(asset_server.load("textures/parallax_example/cube_color.png")),
normal_map_texture: Some(normal_handle),
// The depth map is a greyscale texture where black is the highest level and
// white the lowest.
depth_map: Some(asset_server.load("textures/parallax_example/cube_depth.png")),
parallax_depth_scale,
parallax_mapping_method: parallax_mapping_method.0,
max_parallax_layer_count,
..default()
});
commands.spawn((
PbrBundle {
mesh: meshes.add(
// NOTE: for normal maps and depth maps to work, the mesh
// needs tangents generated.
Mesh::from(Cuboid::default())
.with_generated_tangents()
.unwrap(),
),
material: parallax_material.clone_weak(),
..default()
},
Spin { speed: 0.3 },
));
let background_cube = meshes.add(
Mesh::from(Cuboid::new(40.0, 40.0, 40.0))
.with_generated_tangents()
.unwrap(),
);
let background_cube_bundle = |translation| {
(
PbrBundle {
transform: Transform::from_translation(translation),
mesh: background_cube.clone(),
material: parallax_material.clone(),
..default()
},
Spin { speed: -0.1 },
)
};
commands.spawn(background_cube_bundle(Vec3::new(45., 0., 0.)));
commands.spawn(background_cube_bundle(Vec3::new(-45., 0., 0.)));
commands.spawn(background_cube_bundle(Vec3::new(0., 0., 45.)));
commands.spawn(background_cube_bundle(Vec3::new(0., 0., -45.)));
let style = TextStyle::default();
// example instructions
commands.spawn(
TextBundle::from_sections(vec![
TextSection::new(
format!("Parallax depth scale: {parallax_depth_scale:.5}\n"),
style.clone(),
),
TextSection::new(
format!("Layers: {max_parallax_layer_count:.0}\n"),
style.clone(),
),
TextSection::new(format!("{parallax_mapping_method}\n"), style.clone()),
TextSection::new("\n\n", style.clone()),
TextSection::new("Controls:\n", style.clone()),
TextSection::new("Left click - Change view angle\n", style.clone()),
TextSection::new(
"1/2 - Decrease/Increase parallax depth scale\n",
style.clone(),
),
TextSection::new("3/4 - Decrease/Increase layer count\n", style.clone()),
TextSection::new("Space - Switch parallaxing algorithm\n", style),
])
.with_style(Style {
position_type: PositionType::Absolute,
top: Val::Px(12.0),
left: Val::Px(12.0),
..default()
}),
);
}