# Objective
Currently, the `Ellipse` primitive is represented by a `half_width` and
`half_height`. To improve consistency (similarly to #11434), it might
make more sense to use a `Vec2` `half_size` instead.
Alternatively, to make the elliptical nature clearer, the properties
could also be called `radius_x` and `radius_y`.
Secondly, `Ellipse::new` currently takes a *full* width and height
instead of two radii. I would expect it to take the half-width and
half-height because ellipses and circles are almost always defined using
radii. I wouldn't expect `Circle::new` to take a diameter (if we had
that method).
## Solution
Change `Ellipse` to store a `half_size` and `new` to take the half-width
and half-height.
I also added a `from_size` method similar to `Rectangle::from_size`, and
added the `semi_minor` and `semi_major` helpers to get the
semi-minor/major radius.