Struct BackendFactory 

pub struct BackendFactory;

Creates the best rendering backend available on the host.

The preference order is WebGPU, then WebGL2, then Canvas2D. A canvas can only ever have one kind of context, so the choice has to be made before the first get_context call — which is why the WebGPU probe is asynchronous and the factory is asynchronous too.

Implementations

impl BackendFactory

Inherent implementation of BackendFactory.

pub fn new() -> Self

Returns a factory.

pub async fn create( canvas: &HtmlCanvasElement, preferred: BackendKind, ) -> Option<Box<dyn ChartBackend>>

Creates the best backend for the given canvas.

preferred is the backend the caller would like; the factory falls back to the next one down when the host cannot provide it. The fallback chain is always WebGPU, WebGL2, Canvas2D.

Arguments

• &HtmlCanvasElement - The &HtmlCanvasElement value.
• BackendKind - The BackendKind value.

Returns

• Option<Box<dyn ChartBackend>> - The Option<Box<dyn ChartBackend>> value.

pub fn detect(preferred: BackendKind) -> BackendKind

Returns the backend the host would pick, without creating it.

The check is cheap and synchronous, so a chart can report the backend it is about to use before the asynchronous creation finishes.

Arguments

• BackendKind - A BackendKind parameter.

Returns

• BackendKind - A BackendKind value.

Trait Implementations

impl Clone for BackendFactory

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 BackendFactory

impl Debug for BackendFactory

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

Formats the value using the given formatter.

impl Default for BackendFactory

fn default() -> Self

Returns the “default value” for a type.