Struct Placement 

pub struct Placement {
    pub rect: Rect,
    pub mutators: Vec<Mutator>,
}

Where one frame puts one composition layer: what a host compares to tell a frame worth presenting from one it already shows.

Fields

rect: Rect

The layer’s rectangle, in the coordinates the transforms among mutators lead to.

mutators: Vec<Mutator>

What the containers above the layer do to it, the outermost first: Flutter’s MutatorsStack. A view’s scene begins with its root transform, which takes the framework’s logical pixels to the view’s physical ones.

Implementations

impl Placement

pub fn transform(&self) -> Matrix4

Every transform above the layer in one: Flutter’s transformMatrix, which takes rect’s coordinates to the view’s pixels.

pub fn opacity(&self) -> f64

Every opacity above the layer multiplied, from 0 to 1.

pub fn scale(&self) -> f64

How many of the view’s pixels one unit of the layer’s own coordinates spans along its own horizontal: the scale of every transform above it, the root’s device pixel ratio among them. A producer draws its buffers at the device pixel ratio, so a host shows a buffer at scale / device_pixel_ratio of its size.

pub fn bounds(&self) -> Rect

The box around the layer under every transform above it, in the view’s pixels.

pub fn visible_bounds(&self) -> Rect

bounds cut down to the bounds of every clip above the layer: what a compositor that clips by rectangles alone shows of it. An empty rectangle on the clip’s nearest edge when nothing shows.

Trait Implementations

impl Clone for Placement

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Placement

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

Formats the value using the given formatter.

impl PartialEq for Placement

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Placement