add AsVal trait that helps with constructing Val

[TotalKrill]

Objective

To reduce friction when writing Ui code by letting the code follow the left-to-right mindset.

Mental model: "The width should be 20 pixels" , as in "affect this, with value,of unit"

instead of:
ui_rect.width = Val::Px(20.0);
let us go:
ui_rect.width = 20.px();

Solution

Implement a trait in geometry and implement for the common types

Testing

Tested this by modifying the text_debug example to use this instead and it worked.

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[alice-i-cecile]

I like the syntax, and the implementation is clean. The use a macro is justified here IMO: there's a ton of boilerplate and the code is super simple.

[alice-i-cecile]

Bumping to the 0.16 milestone since this is implementable externally and it's a new feature :)

[alice-i-cecile]

If we're going to be doing this, we should export the trait in the prelude TBH.

[TotalKrill]

It's there in the prelude already. From bevy_ui::prelude

…

On Thu, Oct 10, 2024, 18:56 Alice Cecile ***@***.***> wrote: If we're going to be doing this, we should export the trait in the prelude TBH. — Reply to this email directly, view it on GitHub <#15825 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAYY7BWDQLPBAZ2BG3VZGQTZ22WSXAVCNFSM6AAAAABPXC7IGWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDIMBVGYYTKOBQGY> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[cart]

As a heads up, within the context of BSN I was planning on doing: px(10.0). That will notably play nicer with function reflection in the context of scene assets, as this type of trait-function-reflection requires manual special casing to resolve. Idk if we should have two very similar ways to do this / better to have one way that works in every situation.

[alice-i-cecile]

I'm fine with either solution. This plays a bit nicer with autocomplete. We should merge one or the other for 0.16 though :)

[cart]

This plays a bit nicer with autocomplete

The downside here (if this is in the prelude) is that it adds .px() to autocomplete for every float in every context.

[ickshonpe]

It got shot down the last time I suggested it, but I still think the lowest friction option for users is to change all the Val function arguments to Into<Val> and impl From f32 and i32 for Val mapping them to Val::Px.

[cart]

I'm closing this in favor of px(10.)-style helper functions (or alternatively, exporting Val::Px as Px() in the prelude)