Add methods to get points with axes

[jamwaffles]

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PR description

Adds x_axis and y_axis methods to get a Point or Size with one dimension set to zero. Some places can already use these, but they would be particularly useful in the RoundedRectangle PR. Also adds Point::fill and Size::fill which will be less useful but there are a couple of places they can be used. If these are really useless I don't mind removing them.

[rfuest]

Adds x_axis and y_axis methods to get a Point or Size with one dimension set to zero. Some places can already use these, but they would be particularly useful in the RoundedRectangle PR.

Good idea!

Also adds Point::fill and Size::fill which will be less useful but there are a couple of places they can be used. If these are really useless I don't mind removing them.

I did temporarily add similar methods before, but removed them because they weren't totally necessary for that particular PR and I couldn't come up with a good name. I think we should keep them, but maybe we can come up with a better name, because I wouldn't associate the name fill with a constructor. Normally additional constructors should be prefixed by with_, but that doesn't work well in this case IMO. Maybe new_square?

[jamwaffles]

The name was inspired by nalgebra's Matrix::fill, so might be familiar to some users. An alternative could be new_equal or new_filled perhaps? I think this would then need a shim adding for the features = [ "nalgebra" ] which is easy enough.

I deliberately didn't do a find/replace with the ::fill() methods as it makes most of the examples and tests where it's used a bit less clear IMO. There are a couple of usages in internal code, but we should probably change those manually going forward.

[rfuest]

The name was inspired by nalgebra's Matrix::fill, so might be familiar to some users. An alternative could be new_equal or new_filled perhaps?

Am I right that Matrix::fill isn't a constructor? If that's the case I would go with new_filled, which still remains similar to the nalgebra method.

I think this would then need a shim adding for the features = [ "nalgebra" ] which is easy enough.

Why would this be necessary?

I deliberately didn't do a find/replace with the ::fill() methods as it makes most of the examples and tests where it's used a bit less clear IMO. There are a couple of usages in internal code, but we should probably change those manually going forward.

SGTM

[jamwaffles]

I've changed fill changed to new_filled. It's been a while since I used nalgebra - looks like I got some things confused. Ready to review now :)

[rfuest]

Some nits...

[jamwaffles]

Thanks for the review. Comments addressed

[rfuest]

I did give the name of the constructor another thought and I think we should change it.

IMO the word filled could easily be mistaken for something related to styling, if someone isn't familiar with e-g:

let rect = Rectangle::new(Point::new(10, 20), Size::new_filled(10));
// does this create a "filled rectangle"?

For this case the new_square would work:

let rect = Rectangle::new(Point::new(10, 20), Size::new_square(10));

but Point::new_square might not be the greatest name.

Where can I put my 🚲? 😉

[jamwaffles]

Yes that's true, in context new_filled isn't very clear. That said, new_square doesn't look quite right when used with Ellipse as it makes a circle:

Ellipse::new(Point::new(10, 20), Size::new_square(10));

The best I can come up with is Size::new_equal(u32) or maybe even just Size::equal(u32). If you're not keen on anything equal based, I'll change this PR to new_square, let the docs explain what it does for user who might be confused and leave it there.

Can I share your 🔒 for my 🚲? 😁

[rfuest]

The best I can come up with is Size::new_equal(u32)

OK, let's just go with that.

[jamwaffles]

Changes pushed 👍

[jamwaffles]

Those examples names do look better, thanks

[jamwaffles]

Thanks!