bevy/examples/3d/load_gltf.rs
Cameron 7989cb2650 Add global time scaling (#5752)
# Objective

- Make `Time` API more consistent.
- Support time accel/decel/pause.

## Solution

This is just the `Time` half of #3002. I was told that part isn't controversial.

- Give the "delta time" and "total elapsed time" methods `f32`, `f64`, and `Duration` variants with consistent naming.
- Implement accelerating / decelerating the passage of time.
- Implement stopping time.

---

## Changelog

- Changed `time_since_startup` to `elapsed` because `time.time_*` is just silly.
- Added `relative_speed` and `set_relative_speed` methods.
- Added `is_paused`, `pause`, `unpause` , and methods. (I'd prefer `resume`, but `unpause` matches `Timer` API.)
- Added `raw_*` variants of the "delta time" and "total elapsed time" methods.
- Added `first_update` method because there's a non-zero duration between startup and the first update.

## Migration Guide

- `time.time_since_startup()` -> `time.elapsed()`
- `time.seconds_since_startup()` -> `time.elapsed_seconds_f64()`
- `time.seconds_since_startup_wrapped_f32()` -> `time.elapsed_seconds_wrapped()`

If you aren't sure which to use, most systems should continue to use "scaled" time (e.g. `time.delta_seconds()`). The realtime "unscaled" time measurements (e.g. `time.raw_delta_seconds()`) are mostly for debugging and profiling.
2022-10-22 18:52:29 +00:00

59 lines
1.6 KiB
Rust

//! Loads and renders a glTF file as a scene.
use std::f32::consts::*;
use bevy::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()
});
const HALF_SIZE: f32 = 1.0;
commands.spawn(DirectionalLightBundle {
directional_light: DirectionalLight {
shadow_projection: OrthographicProjection {
left: -HALF_SIZE,
right: HALF_SIZE,
bottom: -HALF_SIZE,
top: HALF_SIZE,
near: -10.0 * HALF_SIZE,
far: 10.0 * HALF_SIZE,
..default()
},
shadows_enabled: true,
..default()
},
..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,
);
}
}