Enum Depth 

#[non_exhaustive]
pub enum Depth {
    Flat,
    Raised,
    Well,
    Sunken,
    Overlay,
}

How a region sits relative to the surface behind it.

Fill and bevel are named together because naming them apart is what let them disagree. Every consumer measured had at least one region carrying a raised bevel over a recessed fill: audiofiles fixed it in raised_frame and recorded the bug in its doc comment, and Balanced Breakfast still had twelve of them a year later. A single name for the pair makes that unrepresentable. #[non_exhaustive] for the same reason as Fill, and in the same release: a depth this renderer has no drawing for should cost it a wildcard arm, not a compile error and a wait on someone else’s publish.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Flat

Level with its surroundings. No edge.

Raised

A card laid on the panel it sits in.

Well

A hole in the panel, with content down inside it. For anything the user looks into: a table body, a tag tree, a text field.

Sunken

Set back from what it sits on, by colour alone. No edge.

The one member carrying a fill without a bevel, so a renderer cannot assume the two arrive together. That is deliberate and it is still the pairing rule: both halves come off the same Depth, so they cannot disagree, and here one half is legitimately absent.

Distinct from Depth::Flat, which has no fill either and inherits. Recessed and level-with are different claims, and only one of them needs a colour.

Overlay

A surface sitting over the page rather than in it. A modal, a popover, a menu.

Takes elevation and no bevel: a surface overlaying the page is lifted off it, and a surface in the page is cut into it. That is the same pairing rule the rest of the enum holds, applied to the one case where the separation is not an edge at all — the lift and the scrim behind it are already saying where the surface is.

Every renderer had the surface before it had this variant. makeover-tui carries Palette::overlay, makeover-immediate gained Palette::elevation at 0.10.0, and makeover-webview emits --elevation-overlay. What was missing was the route from a description to any of them, which is why this is one variant rather than a feature.

Implementations

impl Depth

pub const fn bevel(self) -> Option<Bevel>

The edge this depth is drawn with, if it has one.

pub const fn fill(self) -> Option<Fill>

The surface this depth is filled with.

Depth::Flat has no fill of its own: it inherits whatever it sits on, which is the difference between level-with and painted-the-same-colour.

pub const fn pressed(self) -> Self

Pressing a raised region reads as a well, and nothing else moves.

Depth::Overlay is untouched along with the rest: an overlay is a surface, not a control, so there is nothing there to press.

Trait Implementations

impl Clone for Depth

fn clone(&self) -> Depth

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Depth

impl Debug for Depth

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Depth

impl Hash for Depth

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Depth

fn eq(&self, other: &Depth) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Depth