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ChartBackend

euv_chart

Trait ChartBackend 

Source 
pub trait ChartBackend {
    // Required methods
    fn kind(&self) -> BackendKind;
    fn resize(&mut self, width: f64, height: f64, dpr: f64);
    fn render(&mut self, list: &DisplayList, shaper: &mut TextShaper);
    fn dispose(&mut self);
}
Expand description

A rendering backend for the chart.

The three backends — WebGPU, WebGL2, and Canvas2D — all replay the same display list, so the chart model never has to know which one is in use. That is what keeps the public API identical across backends.

Required Methods§

Source

fn kind(&self) -> BackendKind

Returns the kind of the backend.

§Returns
  • BackendKind - A BackendKind value.
Source

fn resize(&mut self, width: f64, height: f64, dpr: f64)

Prepares the backend for a canvas of the given CSS size, at the given device pixel ratio.

The backends size their drawing buffer to width * dpr by height * dpr physical pixels and scale their coordinate system accordingly, so the model always works in CSS pixels.

§Arguments
  • f64 - A 64-bit float (f64).
Source

fn render(&mut self, list: &DisplayList, shaper: &mut TextShaper)

Replays the display list onto the canvas.

The backend is free to cache whatever it can: the display list is retained between frames, so a chart that has not changed should cost close to nothing to draw.

§Arguments
  • &DisplayList - Shared reference to a DisplayList.
  • &mut TextShaper - Mutable reference to a TextShaper (mutated in place).
Source

fn dispose(&mut self)

Releases the resources the backend holds.

Called when the chart is disposed. The backend must stay usable afterwards — it will simply re-acquire its resources on the next render.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§