Struct RectAlign 

pub struct RectAlign {
    pub parent: Align2,
    pub child: Align2,
}

A parent/child anchor pair describing how a popup attaches to its anchoring widget — the placement half of the Popup API (egui’s RectAlign).

Fields

parent: Align2

Anchor point on the parent (the widget the popup hangs off).

child: Align2

Anchor point on the popup itself.

Implementations

impl RectAlign

pub const BOTTOM_START: Self

Below the widget, left edges aligned.

pub const BOTTOM: Self

Below the widget, horizontally centered.

pub const BOTTOM_END: Self

Below the widget, right edges aligned.

pub const TOP_START: Self

Above the widget, left edges aligned.

pub const TOP: Self

Above the widget, horizontally centered.

pub const TOP_END: Self

Above the widget, right edges aligned.

pub const RIGHT_START: Self

To the right of the widget, top edges aligned.

pub const RIGHT: Self

To the right of the widget, vertically centered.

pub const RIGHT_END: Self

To the right of the widget, bottom edges aligned.

pub const LEFT_START: Self

To the left of the widget, top edges aligned.

pub const LEFT: Self

To the left of the widget, vertically centered.

pub const LEFT_END: Self

To the left of the widget, bottom edges aligned.

pub const PRESETS: [(Self, &'static str); 12]

The named presets with the display names and ordering of egui’s Popups demo preset combo box (egui_demo_lib/src/demo/popups.rs).

pub const MENU_ALIGNS: [Self; 12]

The 12 common menu positions in egui’s fallback-preference order (emath’s RectAlign::MENU_ALIGNS): corner placements first, centered ones last, for use with RectAlign::find_best_align.

pub fn preset_label(self) -> Option<&'static str>

The preset label matching this alignment exactly, or None for an arbitrary (combo-box-composed) pair that isn’t a named preset.

pub fn flip_x(self) -> Self

Mirror the placement on the x-axis (e.g. RIGHT → LEFT).

pub fn flip_y(self) -> Self

Mirror the placement on the y-axis (e.g. BOTTOM_START → TOP_START).

pub fn flip(self) -> Self

Mirror the placement on both axes.

pub fn symmetries(self) -> [Self; 3]

The 3 alternative placements flipped in various ways, for use with RectAlign::find_best_align (mirrors egui’s RectAlign::symmetries).

pub fn find_best_align( values_to_try: impl Iterator<Item = Self>, content_rect: Rect, parent_rect: Rect, gap: f64, expected_size: Size, ) -> Option<Self>

Look for the first candidate placement whose popup rect fits entirely inside content_rect — egui’s overflow-flip (find_best_align).

If no candidate fits, the FIRST candidate is returned (so the caller’s preferred alignment wins and downstream clamping takes over). Returns None only when the iterator is empty.

pub fn place_child(self, parent: Rect, size: Size, gap: f64) -> Rect

Place a popup of size relative to parent, applying gap pixels of separation.

The gap is applied only along axes where the parent and child anchors differ — i.e. the side the popup extends toward — so an edge-attached popup (e.g. RectAlign::BOTTOM_START) gets vertical separation without being nudged sideways.

pub fn place_child_clamped( self, parent: Rect, size: Size, gap: f64, viewport: Size, ) -> Rect

place_child then clamp the result fully inside viewport, leaving a small margin — so a popup near an edge stays on-screen, matching how the menu system clamps its panels.

Trait Implementations

impl Clone for RectAlign

fn clone(&self) -> RectAlign

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RectAlign

impl Debug for RectAlign

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

Formats the value using the given formatter.

impl Eq for RectAlign

impl PartialEq for RectAlign

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for RectAlign