## Support Warning

WebGPU is currently only supported on Chrome starting with version 113, and only on desktop. If they don't work on your configuration, you can check the WebGL2 examples here.
rotation.rs:

```
//! Demonstrates rotating entities in 2D using quaternions.
use *;
const BOUNDS: Vec2 = new;
/// player component
/// snap to player ship behavior
;
/// rotate to face player ship behavior
/// Add the game's entities to our world and creates an orthographic camera for 2D rendering.
///
/// The Bevy coordinate system is the same for 2D and 3D, in terms of 2D this means that:
///
/// * `X` axis goes from left to right (`+X` points right)
/// * `Y` axis goes from bottom to top (`+Y` point up)
/// * `Z` axis goes from far to near (`+Z` points towards you, out of the screen)
///
/// The origin is at the center of the screen.
/// Demonstrates applying rotation and movement based on keyboard input.
/// Demonstrates snapping the enemy ship to face the player ship immediately.
/// Demonstrates rotating an enemy ship to face the player ship at a given rotation speed.
///
/// This method uses the vector dot product to determine if the enemy is facing the player and
/// if not, which way to rotate to face the player. The dot product on two unit length vectors
/// will return a value between -1.0 and +1.0 which tells us the following about the two vectors:
///
/// * If the result is 1.0 the vectors are pointing in the same direction, the angle between them is
/// 0 degrees.
/// * If the result is 0.0 the vectors are perpendicular, the angle between them is 90 degrees.
/// * If the result is -1.0 the vectors are parallel but pointing in opposite directions, the angle
/// between them is 180 degrees.
/// * If the result is positive the vectors are pointing in roughly the same direction, the angle
/// between them is greater than 0 and less than 90 degrees.
/// * If the result is negative the vectors are pointing in roughly opposite directions, the angle
/// between them is greater than 90 and less than 180 degrees.
///
/// It is possible to get the angle by taking the arc cosine (`acos`) of the dot product. It is
/// often unnecessary to do this though. Beware than `acos` will return `NaN` if the input is less
/// than -1.0 or greater than 1.0. This can happen even when working with unit vectors due to
/// floating point precision loss, so it pays to clamp your dot product value before calling
/// `acos`.
```