bevy/examples/2d/transparency_2d.rs
François Mockers a9a4b069b6
Make some examples deterministic (#16488)
# Objective

- Improve reproducibility of examples

## Solution

- Use seeded rng when needed
- Use fixed z-ordering when needed

## Testing

```sh
steps=5;
echo "cpu_draw\nparallel_query\nanimated_fox\ntransparency_2d" > test
cargo run -p example-showcase -- run --stop-frame 250 --screenshot-frame 100 --fixed-frame-time 0.05 --example-list test --in-ci;
mv screenshots base;
for prefix in `seq 0 $steps`;
do
  echo step $prefix;
  cargo run -p example-showcase -- run --stop-frame 250 --screenshot-frame 100 --fixed-frame-time 0.05 --example-list test;
  mv screenshots $prefix-screenshots;
done;
mv base screenshots
for prefix in `seq 0 $steps`;
do
  echo check $prefix
  for file in screenshots/*/*;
  do
    echo $file;
    diff $file $prefix-$file;
  done;
done;
```
2024-11-23 18:28:47 +00:00

36 lines
1,012 B
Rust

//! Demonstrates how to use transparency in 2D.
//! Shows 3 bevy logos on top of each other, each with a different amount of transparency.
use bevy::prelude::*;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.run();
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
commands.spawn(Camera2d);
let sprite_handle = asset_server.load("branding/icon.png");
commands.spawn(Sprite::from_image(sprite_handle.clone()));
commands.spawn((
Sprite {
image: sprite_handle.clone(),
// Alpha channel of the color controls transparency.
color: Color::srgba(0.0, 0.0, 1.0, 0.7),
..default()
},
Transform::from_xyz(100.0, 0.0, 0.1),
));
commands.spawn((
Sprite {
image: sprite_handle,
color: Color::srgba(0.0, 1.0, 0.0, 0.3),
..default()
},
Transform::from_xyz(200.0, 0.0, 0.2),
));
}