Struct SizeConstraints 

pub struct SizeConstraints {
    pub min: Option<LogicalSize>,
    pub max: Option<LogicalSize>,
    pub aspect: Option<AspectRatio>,
}

Limits the window system should enforce on an interactive resize.

All three are hints in the strict sense: a tiling window manager honours none of them, and Wayland has no aspect hint at all. Consumers must stay correct when they are ignored — which for aspect means letterboxing in-renderer with AspectRatio::fit, the universal fallback.

Fields

min: Option<LogicalSize>

Smallest client area the user may resize to.

max: Option<LogicalSize>

Largest client area the user may resize to.

aspect: Option<AspectRatio>

Ratio the client area should keep during a resize.

Honoured natively only where ShellCaps::ASPECT_HINT_HONORED is set. Where it is not, a backend picks the nearest aspect-correct size it is allowed to pick and the renderer letterboxes the remainder.

Implementations

impl SizeConstraints

pub const NONE: Self

No constraints at all.

pub const fn min(size: LogicalSize) -> Self

Constraints with a minimum size and nothing else.

pub const fn with_aspect(self, aspect: AspectRatio) -> Self

These constraints with an aspect lock added.

pub fn apply(&self, size: PhysicalSize, scale_factor: f64) -> PhysicalSize

Applies the constraints to a physical size, as a backend that cannot delegate to the window system would.

Clamping happens before the aspect fit, so the result never exceeds max. It can fall below min when an aspect lock demands it: a size that violates the aspect ratio is visibly wrong, while one a few pixels under the minimum is not, and something has to give when the two disagree.

HeadlessShell applies this, which is what makes constraint behaviour testable without a window manager.

Trait Implementations

impl Clone for SizeConstraints

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SizeConstraints

impl Debug for SizeConstraints

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

Formats the value using the given formatter.

impl Default for SizeConstraints

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for SizeConstraints

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for SizeConstraints