Move bevy_math Reflect impls

[Olle-Lukowski]

Objective

Fixes #13456

Solution

Moved bevy_math's Reflect impls from bevy_reflect to bevy_math.

Quick note

I accidentally used the same commit message while resolving a merge conflict (first time I had to resolve a conflict). Sorry about that.

[MrGVSV]

We might also want to consider registering these types somewhere if they're not already. Maybe in bevy_core?

[Olle-Lukowski]

Oops, forgot to actually update the code after removing the feature. my bad.

[Olle-Lukowski]

Alright, ready for review now @MrGVSV @alice-i-cecile. sorry for the many issues with my commits, was very tired but wanted to finish this anyway.

[MrGVSV]

Nit: Could we avoid glob importing here? The serialize feature really only applies to ReflectSerialize and ReflectDeserialize. Other items, like Reflect and ReflectDefault, don't require that feature. I think specifying the items manually clarifies why this particular feature gate is used.

[Olle-Lukowski]

Yeah sure, I'll go ahead and update it along with your other suggestions, they are all valid concerns.

[MrGVSV]

Thank you!

[MrGVSV]

Nit: We can avoid the bevy_reflect:: prefix on all of these if we change the import up top to something like:

#[cfg(feature = "bevy_reflect")]
use bevy_reflect::Reflect;
#[cfg(all(feature = "bevy_reflect", feature = "serialize"))]
use bevy_reflect::{ReflectDeserialize, ReflectSerialize};

This isn't mandatory, but since we'll probably need to add a separate import for ReflectDefault anyways, we might as well.

[MrGVSV]

Some of these types also implement Default, which means we should probably register ReflectDefault as well:

reflect(Debug, PartialEq, Default)

[Olle-Lukowski]

Also, the reason I didn't derive the traits on things like Arc2d is that it wasn't manually implemented before my changes either, so I wanted to ask it here if there was a reason for that or if that was a mistake (and should be corrected).

[mweatherley]

Also, the reason I didn't derive the traits on things like Arc2d is that it wasn't manually implemented before my changes either, so I wanted to ask it here if there was a reason for that or if that was a mistake (and should be corrected).

I'm pretty sure that's just because those are very new and never had Reflect implemented anywhere. Adding them would be fine!

[Olle-Lukowski]

Also, the reason I didn't derive the traits on things like Arc2d is that it wasn't manually implemented before my changes either, so I wanted to ask it here if there was a reason for that or if that was a mistake (and should be corrected).

I'm pretty sure that's just because those are very new and never had Reflect implemented anywhere. Adding them would be fine!

Should I simply implement it for all math types? Even older types like Ray2d didn't have it yet. IMO that should be a follow up PR.

[mweatherley]

Should I simply implement it for all math types? Even older types like Ray2d didn't have it yet. IMO that should be a follow up PR.

Doing it in a follow-up probably makes more sense, yeah.

[Olle-Lukowski]

I'll open an issue for implementing the reflect traits for all math types. I'll work on it when this gets merged.