Normals test for deferred PR

deferred_rendering.rs

//! This example compares Forward, Forward + Prepass, and Deferred rendering.

use std::f32::consts::*;

use bevy::{
    core_pipeline::{
        fxaa::Fxaa,
        prepass::{DeferredPrepass, DepthPrepass, MotionVectorPrepass, NormalPrepass},
    },
    pbr::{CascadeShadowConfigBuilder, DirectionalLightShadowMap},
    pbr::{DefaultOpaqueRendererMethod, NotShadowCaster, OpaqueRendererMethod},
    prelude::*,
    render::render_resource::TextureFormat,
};

fn main() {
    App::new()
        .insert_resource(Msaa::Off)
        .insert_resource(DefaultOpaqueRendererMethod(OpaqueRendererMethod::Deferred))
        .insert_resource(ClearColor(Color::rgb_linear(0.05, 0.05, 0.05)))
        .insert_resource(AmbientLight {
            color: Color::WHITE,
            brightness: 0.0,
        })
        .insert_resource(DirectionalLightShadowMap { size: 4096 })
        .add_plugins(DefaultPlugins)
        .insert_resource(Normal(None))
        .insert_resource(Pause(true))
        .add_systems(Startup, (setup, setup_parallax))
        .add_systems(
            Update,
            (
                animate_light_direction,
                switch_mode,
                spin,
                update_normal,
                camera_controller,
                swap_material,
            ),
        )
        .run();
}

fn setup(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
    mut materials: ResMut<Assets<StandardMaterial>>,
    mut meshes: ResMut<Assets<Mesh>>,
) {
    commands.spawn((
        Camera3dBundle {
            camera: Camera {
                //hdr: true,
                ..default()
            },
            transform: Transform::from_xyz(0.7, 0.7, 1.0)
                .looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y),
            ..default()
        },
        FogSettings {
            color: Color::rgba(0.05, 0.05, 0.05, 1.0),
            falloff: FogFalloff::Linear {
                start: 1.0,
                end: 8.0,
            },
            ..default()
        },
        EnvironmentMapLight {
            diffuse_map: asset_server.load("environment_maps/pisa_diffuse_rgb9e5_zstd.ktx2"),
            specular_map: asset_server.load("environment_maps/pisa_specular_rgb9e5_zstd.ktx2"),
        },
        DepthPrepass,
        MotionVectorPrepass,
        DeferredPrepass,
        Fxaa::default(),
        CameraController::default(),
    ));

    commands.spawn(DirectionalLightBundle {
        directional_light: DirectionalLight {
            shadows_enabled: true,
            ..default()
        },
        cascade_shadow_config: CascadeShadowConfigBuilder {
            num_cascades: 3,
            maximum_distance: 10.0,
            ..default()
        }
        .into(),
        transform: Transform::from_rotation(Quat::from_euler(EulerRot::ZYX, 0.0, 0.0, -FRAC_PI_4)),
        ..default()
    });

    // FlightHelmet
    let helmet_scene = asset_server.load("models/FlightHelmet/FlightHelmet.gltf#Scene0");

    commands.spawn(SceneBundle {
        scene: helmet_scene.clone(),
        ..default()
    });
    commands.spawn(SceneBundle {
        scene: helmet_scene,
        transform: Transform::from_xyz(-3.0, 0.0, -3.0),
        ..default()
    });

    let shiney = StandardMaterial {
        metallic: 1.0,
        reflectance: 1.0,
        perceptual_roughness: 0.0,
        ..default()
    };

    commands.spawn(Shiney(materials.add(shiney)));

    let mut forward_mat: StandardMaterial = Color::rgb(0.1, 0.2, 0.1).into();
    forward_mat.opaque_render_method = Some(OpaqueRendererMethod::Forward);
    let forward_mat_h = materials.add(forward_mat);

    // Plane
    commands.spawn(PbrBundle {
        mesh: meshes.add(shape::Plane::from_size(50.0).into()),
        material: forward_mat_h.clone(),
        ..default()
    });

    let cube_h = meshes.add(Mesh::from(shape::Cube { size: 0.1 }));
    let sphere_h = meshes.add(Mesh::from(shape::UVSphere {
        radius: 0.125,
        sectors: 128,
        stacks: 128,
    }));

    // Cubes
    commands.spawn(PbrBundle {
        mesh: cube_h.clone(),
        material: forward_mat_h.clone(),
        transform: Transform::from_xyz(-0.3, 0.5, -0.2),
        ..default()
    });
    commands.spawn(PbrBundle {
        mesh: cube_h,
        material: forward_mat_h,
        transform: Transform::from_xyz(0.2, 0.5, 0.2),
        ..default()
    });

    let sphere_color = Color::rgb(10.0, 4.0, 1.0);
    let sphere_pos = Transform::from_xyz(0.4, 0.5, -0.8);
    // Emissive sphere
    let mut unlit_mat: StandardMaterial = sphere_color.into();
    unlit_mat.unlit = true;
    commands.spawn((
        PbrBundle {
            mesh: sphere_h.clone(),
            material: materials.add(unlit_mat),
            transform: sphere_pos,
            ..default()
        },
        NotShadowCaster,
    ));
    // Light
    commands.spawn(PointLightBundle {
        point_light: PointLight {
            intensity: 1.0,
            radius: 0.125,
            shadows_enabled: true,
            color: sphere_color,
            ..default()
        },
        transform: sphere_pos,
        ..default()
    });

    // Spheres
    for i in 0..6 {
        let j = i % 3;
        let s_val = if i < 3 { 0.0 } else { 0.2 };
        let material = if j == 0 {
            materials.add(StandardMaterial {
                base_color: Color::rgb(s_val, s_val, 1.0),
                perceptual_roughness: 0.089,
                metallic: 0.0,
                ..default()
            })
        } else if j == 1 {
            materials.add(StandardMaterial {
                base_color: Color::rgb(s_val, 1.0, s_val),
                perceptual_roughness: 0.089,
                metallic: 0.0,
                ..default()
            })
        } else {
            materials.add(StandardMaterial {
                base_color: Color::rgb(1.0, s_val, s_val),
                perceptual_roughness: 0.089,
                metallic: 0.0,
                ..default()
            })
        };
        commands.spawn(PbrBundle {
            mesh: sphere_h.clone(),
            material,
            transform: Transform::from_xyz(
                j as f32 * 0.25 + if i < 3 { -0.15 } else { 0.15 } - 0.4,
                0.125,
                -j as f32 * 0.25 + if i < 3 { -0.15 } else { 0.15 } + 0.4,
            ),
            ..default()
        });
    }

    // Example instructions
    commands.spawn(
        TextBundle::from_section(
            "",
            TextStyle {
                font_size: 18.0,
                color: Color::WHITE,
                ..default()
            },
        )
        .with_style(Style {
            position_type: PositionType::Absolute,
            top: Val::Px(10.0),
            left: Val::Px(10.0),
            ..default()
        }),
    );
}

#[derive(Resource)]
struct Pause(bool);

fn animate_light_direction(
    time: Res<Time>,
    mut query: Query<&mut Transform, With<DirectionalLight>>,
    pause: Res<Pause>,
) {
    if pause.0 {
        return;
    }
    for mut transform in &mut query {
        transform.rotation = Quat::from_euler(
            EulerRot::ZYX,
            0.0,
            time.elapsed_seconds() * PI / 5.0,
            -FRAC_PI_4,
        );
    }
}

fn setup_parallax(
    mut commands: Commands,
    mut materials: ResMut<Assets<StandardMaterial>>,
    mut meshes: ResMut<Assets<Mesh>>,
    mut normal: ResMut<Normal>,
    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("textures/parallax_example/cube_normal.png");
    normal.0 = Some(normal_handle);

    let mut cube: Mesh = shape::Cube { size: 0.15 }.into();

    // NOTE: for normal maps and depth maps to work, the mesh
    // needs tangents generated.
    cube.generate_tangents().unwrap();

    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: normal.0.clone(),
        // 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: 0.09,
        parallax_mapping_method: ParallaxMappingMethod::Relief { max_steps: 4 },
        max_parallax_layer_count: 5.0f32.exp2(),
        ..default()
    });
    commands.spawn((
        PbrBundle {
            mesh: meshes.add(cube),
            material: parallax_material,
            transform: Transform::from_xyz(0.4, 0.2, -0.8),
            ..default()
        },
        Spin { speed: 0.3 },
    ));
}

/// Store handle of the normal to later modify its format in [`update_normal`].
#[derive(Resource)]
struct Normal(Option<Handle<Image>>);

// See `examples/3d/parallax_mapping.rs` example for reasoning
fn update_normal(
    mut already_ran: Local<bool>,
    mut images: ResMut<Assets<Image>>,
    normal: Res<Normal>,
) {
    if *already_ran {
        return;
    }
    if let Some(normal) = normal.0.as_ref() {
        if let Some(image) = images.get_mut(normal) {
            image.texture_descriptor.format = TextureFormat::Rgba8Unorm;
            *already_ran = true;
        }
    }
}

#[derive(Component)]
struct Spin {
    speed: f32,
}

fn spin(time: Res<Time>, mut query: Query<(&mut Transform, &Spin)>, pause: Res<Pause>) {
    if pause.0 {
        return;
    }
    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());
    }
}

#[derive(Resource, Default)]
enum DefaultRenderMode {
    #[default]
    Deferred,
    Forward,
    ForwardPrepass,
}

#[allow(clippy::too_many_arguments)]
fn switch_mode(
    mut text: Query<&mut Text>,
    mut commands: Commands,
    keys: Res<Input<KeyCode>>,
    mut default_opaque_renderer_method: ResMut<DefaultOpaqueRendererMethod>,
    mut materials: ResMut<Assets<StandardMaterial>>,
    cameras: Query<Entity, With<Camera>>,
    mut pause: ResMut<Pause>,
    mut hide_ui: Local<bool>,
    mut mode: Local<DefaultRenderMode>,
) {
    let mut text = text.single_mut();
    let text = &mut text.sections[0].value;

    text.clear();

    if keys.just_pressed(KeyCode::Space) {
        pause.0 = !pause.0;
    }

    if keys.just_pressed(KeyCode::Key1) {
        *mode = DefaultRenderMode::Deferred;
        default_opaque_renderer_method.0 = OpaqueRendererMethod::Deferred;
        println!("DefaultOpaqueRendererMethod: Deferred");
        for _ in materials.iter_mut() {}
        for camera in &cameras {
            commands.entity(camera).remove::<NormalPrepass>();
            commands.entity(camera).insert(DepthPrepass);
            commands.entity(camera).insert(MotionVectorPrepass);
            commands.entity(camera).insert(DeferredPrepass);
        }
    }
    if keys.just_pressed(KeyCode::Key2) {
        *mode = DefaultRenderMode::Forward;
        default_opaque_renderer_method.0 = OpaqueRendererMethod::Forward;
        println!("DefaultOpaqueRendererMethod: Forward");
        for _ in materials.iter_mut() {}
        for camera in &cameras {
            commands.entity(camera).remove::<NormalPrepass>();
            commands.entity(camera).remove::<DepthPrepass>();
            commands.entity(camera).remove::<MotionVectorPrepass>();
            commands.entity(camera).remove::<DeferredPrepass>();
        }
    }
    if keys.just_pressed(KeyCode::Key3) {
        *mode = DefaultRenderMode::ForwardPrepass;
        default_opaque_renderer_method.0 = OpaqueRendererMethod::Forward;
        println!("DefaultOpaqueRendererMethod: Forward + Prepass");
        for _ in materials.iter_mut() {}
        for camera in &cameras {
            commands.entity(camera).insert(NormalPrepass);
            commands.entity(camera).insert(DepthPrepass);
            commands.entity(camera).insert(MotionVectorPrepass);
            commands.entity(camera).remove::<DeferredPrepass>();
        }
    }

    if keys.just_pressed(KeyCode::H) {
        *hide_ui = !*hide_ui;
    }

    if !*hide_ui {
        text.push_str("(H) Hide UI\n");
        text.push_str("(Space) Play/Pause\n\n");
        text.push_str("Rendering Method:\n");

        text.push_str(&format!(
            "(1) {} Deferred\n",
            if let DefaultRenderMode::Deferred = *mode {
                ">"
            } else {
                ""
            }
        ));
        text.push_str(&format!(
            "(2) {} Forward\n",
            if let DefaultRenderMode::Forward = *mode {
                ">"
            } else {
                ""
            }
        ));
        text.push_str(&format!(
            "(3) {} Forward + Prepass\n",
            if let DefaultRenderMode::ForwardPrepass = *mode {
                ">"
            } else {
                ""
            }
        ));
    }
}

#[derive(Component)]
struct Shiney(Handle<StandardMaterial>);
#[derive(Component)]
struct ShineyIsSet;

fn swap_material(
    mut commands: Commands,
    mut has_standard_mat: Query<(Entity, &mut Handle<StandardMaterial>), Without<ShineyIsSet>>,
    shiney_mat: Query<&Shiney>,
) {
    let shiney_mat = shiney_mat.single();
    for (entity, mut m) in has_standard_mat.iter_mut() {
        *m = shiney_mat.0.clone();
        commands.entity(entity).insert(ShineyIsSet);
    }
}

#[derive(Component)]
pub struct CameraController {
    pub enabled: bool,
    pub initialized: bool,
    pub sensitivity: f32,
    pub key_forward: KeyCode,
    pub key_back: KeyCode,
    pub key_left: KeyCode,
    pub key_right: KeyCode,
    pub key_up: KeyCode,
    pub key_down: KeyCode,
    pub key_run: KeyCode,
    pub mouse_key_enable_mouse: MouseButton,
    pub keyboard_key_enable_mouse: KeyCode,
    pub walk_speed: f32,
    pub run_speed: f32,
    pub friction: f32,
    pub pitch: f32,
    pub yaw: f32,
    pub velocity: Vec3,
}

impl Default for CameraController {
    fn default() -> Self {
        Self {
            enabled: true,
            initialized: false,
            sensitivity: 0.5,
            key_forward: KeyCode::W,
            key_back: KeyCode::S,
            key_left: KeyCode::A,
            key_right: KeyCode::D,
            key_up: KeyCode::E,
            key_down: KeyCode::Q,
            key_run: KeyCode::ShiftLeft,
            mouse_key_enable_mouse: MouseButton::Left,
            keyboard_key_enable_mouse: KeyCode::M,
            walk_speed: 0.5,
            run_speed: 3.0,
            friction: 0.5,
            pitch: 0.0,
            yaw: 0.0,
            velocity: Vec3::ZERO,
        }
    }
}

pub fn camera_controller(
    time: Res<Time>,
    mut mouse_events: EventReader<bevy::input::mouse::MouseMotion>,
    mouse_button_input: Res<Input<MouseButton>>,
    key_input: Res<Input<KeyCode>>,
    mut move_toggled: Local<bool>,
    mut query: Query<(&mut Transform, &mut CameraController), With<Camera>>,
) {
    let dt = time.delta_seconds();

    if let Ok((mut transform, mut options)) = query.get_single_mut() {
        if !options.initialized {
            let (yaw, pitch, _roll) = transform.rotation.to_euler(EulerRot::YXZ);
            options.yaw = yaw;
            options.pitch = pitch;
            options.initialized = true;
        }
        if !options.enabled {
            return;
        }

        // Handle key input
        let mut axis_input = Vec3::ZERO;
        if key_input.pressed(options.key_forward) {
            axis_input.z += 1.0;
        }
        if key_input.pressed(options.key_back) {
            axis_input.z -= 1.0;
        }
        if key_input.pressed(options.key_right) {
            axis_input.x += 1.0;
        }
        if key_input.pressed(options.key_left) {
            axis_input.x -= 1.0;
        }
        if key_input.pressed(options.key_up) {
            axis_input.y += 1.0;
        }
        if key_input.pressed(options.key_down) {
            axis_input.y -= 1.0;
        }
        if key_input.just_pressed(options.keyboard_key_enable_mouse) {
            *move_toggled = !*move_toggled;
        }

        // Apply movement update
        if axis_input != Vec3::ZERO {
            let max_speed = if key_input.pressed(options.key_run) {
                options.run_speed
            } else {
                options.walk_speed
            };
            options.velocity = axis_input.normalize() * max_speed;
        } else {
            let friction = options.friction.clamp(0.0, 1.0);
            options.velocity *= 1.0 - friction;
            if options.velocity.length_squared() < 1e-6 {
                options.velocity = Vec3::ZERO;
            }
        }
        let forward = transform.forward();
        let right = transform.right();
        transform.translation += options.velocity.x * dt * right
            + options.velocity.y * dt * Vec3::Y
            + options.velocity.z * dt * forward;

        // Handle mouse input
        let mut mouse_delta = Vec2::ZERO;
        if mouse_button_input.pressed(options.mouse_key_enable_mouse) || *move_toggled {
            for mouse_event in mouse_events.iter() {
                mouse_delta += mouse_event.delta;
            }
        }

        if mouse_delta != Vec2::ZERO {
            // Apply look update
            options.pitch = (options.pitch - mouse_delta.y * 0.5 * options.sensitivity * dt)
                .clamp(-PI / 2., PI / 2.);
            options.yaw -= mouse_delta.x * options.sensitivity * dt;
            transform.rotation = Quat::from_euler(EulerRot::ZYX, 0.0, options.yaw, options.pitch);
        }
    }
}