# Examples

These examples demonstrate the main features of Bevy and how to use them.
To run an example, use the command `cargo run --example <Example>`, and add the option `--features x11` or `--features wayland` to force the example to run on a specific window compositor, e.g.
```
cargo run --features wayland --example hello_world
```

## Hello, World!

Example | Main | Description
--- | --- | ---
`hello_world` | [`hello_world.rs`](./hello_world.rs) | Runs a minimal example that outputs "hello world"

## 2D Rendering

Example | Main | Description
--- | --- | ---
`sprite` | [`2d/sprite.rs`](./2d/sprite.rs) | Renders a sprite
`sprite_sheet` | [`2d/sprite_sheet.rs`](./2d/sprite_sheet.rs) | Renders an animated sprite
`texture_atlas` | [`2d/texture_atlas.rs`](./2d/texture_atlas.rs) | Generates a texture atlas (sprite sheet) from individual sprites

## 3D Rendering

Example | File | Description
--- | --- | ---
`load_model` | [`3d/load_model.rs`](./3d/load_model.rs) | Loads and renders a simple model
`msaa` | [`3d/msaa.rs`](./3d/msaa.rs) | Configures MSAA (Multi-Sample Anti-Aliasing) for smoother edges
`parenting` | [`3d/parenting.rs`](./3d/parenting.rs) | Demonstrates parent->child relationships and relative transformations
`3d_scene` | [`3d/3d_scene.rs`](./3d/3d_scene.rs) | Simple 3D scene with basic shapes and lighting
`spawner` | [`3d/spawner.rs`](./3d/spawner.rs) | Renders a large number of cubes with changing position and material
`texture` | [`3d/texture.rs`](./3d/texture.rs) | Shows configuration of texture materials
`z_sort_debug` | [`3d/z_sort_debug.rs`](./3d/z_sort_debug.rs) | Visualizes camera Z-ordering

## Application

Example | File | Description
--- | --- | ---
`empty` | [`app/empty.rs`](./app/empty.rs) | An empty application (does nothing)
`empty_defaults` | [`app/empty_defaults.rs`](./app/empty_defaults.rs) | An empty application with default plugins
`headless` | [`app/headless.rs`](./app/headless.rs) | An application that runs without default plugins
`plugin` | [`app/plugin.rs`](./app/plugin.rs) | Demonstrates the creation and registration of a custom plugin
`thread_pool_resources` | [`app/thread_pool_resources.rs`](./app/thread_pool_resources.rs) | Creates and customizes the internal thread pool

## Assets

Example | File | Description
--- | --- | ---
`asset_loading` | [`asset/asset_loading.rs`](./asset/asset_loading.rs) | Demonstrates various methods to load assets
`hot_asset_reloading` | [`asset/hot_asset_reloading.rs`](./asset/hot_asset_reloading.rs) | Demonstrates automatic reloading of assets when modified on disk

## Audio

Example | File | Description
--- | --- | ---
`audio` | [`audio/audio.rs`](./audio/audio.rs) | Shows how to load and play an audio file

## Diagnostics

Example | File | Description
--- | --- | ---
`custom_diagnostic` | [`diagnostics/custom_diagnostic.rs`](./diagnostics/custom_diagnostic.rs) | Shows how to create a custom diagnostic
`print_diagnostics` | [`diagnostics/print_diagnostics.rs`](./diagnostics/print_diagnostics.rs) | Add a plugin that prints diagnostics to the console

## ECS (Entity Component System)

Example | File | Description
--- | --- | ---
`event` | [`ecs/event.rs`](./ecs/event.rs) | Illustrates event creation, activation, and reception
`ecs_guide` | [`ecs/ecs_guide.rs`](./ecs/ecs_guide.rs) | Full guide to Bevy's ECS
`parallel_query` | [`ecs/parallel_query.rs`](./ecs/parallel_query.rs) | Illustrates parallel queries with `ParallelIterator`
`startup_system` | [`ecs/startup_system.rs`](./ecs/startup_system.rs) | Demonstrates a startup system (one that runs once when the app starts up)

## Games

Example | File | Description
--- | --- | ---
`breakout` | [`game/breakout.rs`](./game/breakout.rs) | An implementation of the classic game "Breakout"

## Input

Example | File | Description
--- | --- | ---
`mouse_input` | [`input/mouse_input.rs`](./input/mouse_input.rs) | Demonstrates handling a mouse button press/release
`mouse_input_events` | [`input/mouse_input_events.rs`](./input/mouse_input_events.rs) | Prints out all mouse events (buttons, movement, etc.)
`keyboard_input` | [`input/keyboard_input.rs`](./input/keyboard_input.rs) | Demonstrates handling a key press/release
`keyboard_input_events` | [`input/keyboard_input_events.rs`](./input/keyboard_input_events.rs) | Prints out all keyboard events

## Scene

Example | File | Description
--- | --- | ---
`scene` | [`scene/scene.rs`](./scene/scene.rs) | Demonstrates loading from and saving scenes to files
`properties` | [`scene/properties.rs`](./scene/properties.rs) | Demonstrates Properties (similar to reflections in other languages) in Bevy

## Shaders

Example | File | Description
--- | --- | ---
`shader_custom_material` | [`shader/shader_custom_material.rs`](./shader/shader_custom_material.rs) | Illustrates creating a custom material and a shader that uses it
`shader_defs` | [`shader/shader_defs.rs`](./shader/shader_defs.rs) | Demonstrates creating a custom material that uses "shaders defs" (a tool to selectively toggle parts of a shader)

## UI (User Interface)

Example | File | Description
--- | --- | ---
`button` | [`ui/button.rs`](./ui/button.rs) | Illustrates creating and updating a button
`text` | [`ui/text.rs`](./ui/text.rs) | Illustrates creating and updating text
`font_atlas_debug` | [`ui/font_atlas_debug.rs`](./ui/font_atlas_debug.rs) | Illustrates how FontAtlases are populated (used to optimize text rendering internally)
`ui` | [`ui/ui.rs`](./ui/ui.rs) | Illustrates various features of Bevy UI

## Window

Example | File | Description
--- | --- | ---
`clear_color` | [`window/clear_color.rs`](./window/clear_color.rs) | Creates a solid color window
`multiple_windows` | [`window/multiple_windows.rs`](./window/multiple_windows.rs) | Creates two windows and cameras viewing the same mesh
`window_settings` | [`window/window_settings.rs`](./window/window_settings.rs) | Demonstrates customizing default window settings

## WASM

#### pre-req

    $ rustup target add wasm32-unknown-unknown
    $ cargo install wasm-bindgen-cli

#### build & run

Following is an example for `headless_wasm`. For other examples in wasm/ directory,
change the `headless_wasm` in the following commands **and edit** `examples/wasm/index.html`
to point to the correct `.js` file.

    $ cargo build --example headless_wasm --target wasm32-unknown-unknown --no-default-features
    $ wasm-bindgen --out-dir examples/wasm/target --target web target/wasm32-unknown-unknown/debug/examples/headless_wasm.wasm

Then serve `examples/wasm` dir to browser. i.e.

    $ basic-http-server examples/wasm