bevy/examples/3d/load_gltf.rs
Daniel Chia c3a46822e1 Cascaded shadow maps. (#7064)
Co-authored-by: Robert Swain <robert.swain@gmail.com>

# Objective

Implements cascaded shadow maps for directional lights, which produces better quality shadows without needing excessively large shadow maps.

Fixes #3629

Before
![image](https://user-images.githubusercontent.com/1222141/210061203-bbd965a4-8d11-4cec-9a88-67fc59d0819f.png)

After
![image](https://user-images.githubusercontent.com/1222141/210061334-2ff15334-e6d7-4a31-9314-f34a7805cac6.png)


## Solution

Rather than rendering a single shadow map for directional light, the view frustum is divided into a series of cascades, each of which gets its own shadow map. The correct cascade is then sampled for shadow determination.

---

## Changelog

Directional lights now use cascaded shadow maps for improved shadow quality.


## Migration Guide

You no longer have to manually specify a `shadow_projection` for a directional light, and these settings should be removed. If customization of how cascaded shadow maps work is desired, modify the `CascadeShadowConfig` component instead.
2023-01-25 12:35:39 +00:00

53 lines
1.5 KiB
Rust

//! Loads and renders a glTF file as a scene.
use std::f32::consts::*;
use bevy::{pbr::CascadeShadowConfig, prelude::*};
fn main() {
App::new()
.insert_resource(AmbientLight {
color: Color::WHITE,
brightness: 1.0 / 5.0f32,
})
.add_plugins(DefaultPlugins)
.add_startup_system(setup)
.add_system(animate_light_direction)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(0.7, 0.7, 1.0).looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y),
..default()
});
commands.spawn(DirectionalLightBundle {
directional_light: DirectionalLight {
shadows_enabled: true,
..default()
},
// This is a relatively small scene, so use tighter shadow
// cascade bounds than the default for better quality.
cascade_shadow_config: CascadeShadowConfig::new(1, 1.1, 1.5, 0.3),
..default()
});
commands.spawn(SceneBundle {
scene: asset_server.load("models/FlightHelmet/FlightHelmet.gltf#Scene0"),
..default()
});
}
fn animate_light_direction(
time: Res<Time>,
mut query: Query<&mut Transform, With<DirectionalLight>>,
) {
for mut transform in &mut query {
transform.rotation = Quat::from_euler(
EulerRot::ZYX,
0.0,
time.elapsed_seconds() * PI / 5.0,
-FRAC_PI_4,
);
}
}