# Objective
The `Anchor` component doesn't need to be a enum. The variants are just
mapped to `Vec2`s so it could be changed to a newtype with associated
const values, saving the space needed for the discriminator by the enum.
Also there was no benefit I think in hiding the underlying `Vec2`
representation of `Anchor`s.
Suggested by @atlv24.
Fixes#18459Fixes#18460
## Solution
Change `Anchor` to a struct newtyping a `Vec2`, and its variants into
associated constants.
## Migration Guide
The anchor component has been changed from an enum to a struct newtyping
a `Vec2`. The `Custom` variant has been removed, instead to construct a
custom `Anchor` use its tuple constructor:
```rust
Sprite {
anchor: Anchor(Vec2::new(0.25, 0.4)),
..default()
}
```
The other enum variants have been replaced with corresponding constants:
* `Anchor::BottomLeft` to `Anchor::BOTTOM_LEFT`
* `Anchor::Center` to `Anchor::CENTER`
* `Anchor::TopRight` to `Anchor::TOP_RIGHT`
* .. and so on for the remaining variants