Trait DrawBackend 

pub trait DrawBackend {
    // Required methods
    fn draw_circle(
        &mut self,
        center: (f64, f64),
        radius: f64,
        style: &PointStyle,
    ) -> Result<(), RenderError>;
    fn draw_line(
        &mut self,
        points: &[(f64, f64)],
        style: &LineStyle,
    ) -> Result<(), RenderError>;
    fn draw_rect(
        &mut self,
        top_left: (f64, f64),
        bottom_right: (f64, f64),
        style: &RectStyle,
    ) -> Result<(), RenderError>;
    fn draw_text(
        &mut self,
        text: &str,
        pos: (f64, f64),
        style: &TextStyle,
    ) -> Result<(), RenderError>;
    fn draw_polygon(
        &mut self,
        points: &[(f64, f64)],
        style: &RectStyle,
    ) -> Result<(), RenderError>;
    fn plot_area(&self) -> Rect;
    fn total_area(&self) -> Rect;

    // Provided methods
    fn set_tooltip(&mut self, _tooltip: Option<String>) { ... }
    fn set_mark_axis(&mut self, _key: Option<String>) { ... }
    fn set_mark_series(&mut self, _series: Option<String>) { ... }
    fn set_mark_value(&mut self, _value: Option<String>) { ... }
    fn set_mark_geom(&mut self, _geom: Option<&str>) { ... }
    fn warn(&mut self, _message: String) { ... }
    fn set_mark_part(&mut self, _part: Option<&str>) { ... }
    fn set_mark_attrs(&mut self, _attrs: Vec<(String, String)>) { ... }
    fn wants_formatted_values(&self) -> bool { ... }
    fn set_mark_fvalue(&mut self, _value: Option<String>) { ... }
    fn set_mark_fx(&mut self, _value: Option<String>) { ... }
    fn draw_shape(
        &mut self,
        center: (f64, f64),
        radius: f64,
        style: &PointStyle,
    ) -> Result<(), RenderError> { ... }
    fn draw_quadratic(
        &mut self,
        p0: (f64, f64),
        ctrl: (f64, f64),
        p1: (f64, f64),
        style: &LineStyle,
    ) -> Result<(), RenderError> { ... }
}

Our rendering abstraction, independent of plotters details.

Required Methods

fn draw_circle( &mut self, center: (f64, f64), radius: f64, style: &PointStyle, ) -> Result<(), RenderError>

fn draw_line( &mut self, points: &[(f64, f64)], style: &LineStyle, ) -> Result<(), RenderError>

fn draw_rect( &mut self, top_left: (f64, f64), bottom_right: (f64, f64), style: &RectStyle, ) -> Result<(), RenderError>

fn draw_text( &mut self, text: &str, pos: (f64, f64), style: &TextStyle, ) -> Result<(), RenderError>

fn draw_polygon( &mut self, points: &[(f64, f64)], style: &RectStyle, ) -> Result<(), RenderError>

fn plot_area(&self) -> Rect

fn total_area(&self) -> Rect

Provided Methods

fn set_tooltip(&mut self, _tooltip: Option<String>)

Attach a tooltip to subsequently-drawn marks until cleared with None. Backends that produce interactive output (SVG) emit it as a <title> for a native hover tooltip; others ignore it. Default: no-op.

fn set_mark_axis(&mut self, _key: Option<String>)

Attach an axis (x) key to subsequently-drawn marks — SVG emits it as a data-x attribute so a host can group marks by x (axis-pointer tooltip). Default: no-op.

fn set_mark_series(&mut self, _series: Option<String>)

Attach a series key (the colour / fill / group level) to subsequently drawn marks — SVG emits it as data-series, so a host can highlight or filter one series without parsing the tooltip. Default: no-op.

fn set_mark_value(&mut self, _value: Option<String>)

Attach the raw measured value (the unformatted y) to subsequently drawn marks — SVG emits it as data-value. Default: no-op.

fn set_mark_geom(&mut self, _geom: Option<&str>)

Tag subsequently drawn elements as data marks of the named geom (the layer’s Geom::name) until cleared with None. SVG emits class="gg-mark gg-<kind>" (kind from the primitive: point, line, band, bar, text) plus data-geom, so a host can select data marks without matching axes, grid lines or legends. Default: no-op.

fn warn(&mut self, _message: String)

Report a non-fatal problem found while drawing (e.g. labels a repel layout had to drop). Backends that collect warnings (the native SVG backend) append it to the render warnings. Default: ignored.

fn set_mark_part(&mut self, _part: Option<&str>)

Mark subsequently-drawn marks as belonging to a sub-part of a larger geom (e.g. "arrow" for an arrowhead drawn alongside a segment/curve/ path/line). While set, the SVG backend writes data-part="<part>" aria-hidden="true" and omits the <title> tooltip (the part is decorative; the parent mark already carries the semantic info). data-x/data-series/data-value (and any user data-* attrs) are still written. Default: no-op.

fn set_mark_attrs(&mut self, _attrs: Vec<(String, String)>)

Attach arbitrary data-* attributes to subsequently-drawn marks (B1-7’s Aes::data_attr). The SVG backend writes each, escaped; an attr with the same name as a built-in (data-x, data-series, data-value) replaces it rather than duplicating it. An empty Vec clears any previously set attrs. Default: no-op.

fn wants_formatted_values(&self) -> bool

Whether the caller asked for per-mark formatted values (crate::plot::GGPlot::svg_formatted_values, B2-4) — a query a geom checks before doing the (otherwise pointless) work of resolving a scale’s formatter for set_mark_fvalue/set_mark_fx. Default false, so the feature is byte-identical when never turned on.

fn set_mark_fvalue(&mut self, _value: Option<String>)

data-fvalue on subsequently-drawn marks: the “value” aesthetic’s raw data value (y for most geoms, fill for hex/tile), formatted through that aesthetic’s scale (Scale::format_value) — e.g. a de-DE currency string. Only meaningful while wants_formatted_values is true; None clears any previous mark’s value, per row. Default: no-op.

fn set_mark_fx(&mut self, _value: Option<String>)

data-fx on subsequently-drawn marks: the x value formatted through the x scale (e.g. a datetime axis’s ISO/locale date). The SVG backend omits it when it matches the already-written data-x, so a plain numeric x doesn’t get a redundant duplicate attribute. Default: no-op.

fn draw_shape( &mut self, center: (f64, f64), radius: f64, style: &PointStyle, ) -> Result<(), RenderError>

Draw a point with a specific shape. Default delegates to draw_circle for Circle.

fn draw_quadratic( &mut self, p0: (f64, f64), ctrl: (f64, f64), p1: (f64, f64), style: &LineStyle, ) -> Result<(), RenderError>

Draw a quadratic Bézier curve from p0 to p1 with control point ctrl, in pixel space. The default implementation flattens the curve to 32 line segments and draws it with draw_line; backends that support real curves (SVG) should override this. Non-finite input draws nothing.

Dyn Compatibility

This trait is dyn compatible.

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

Implementors

impl DrawBackend for SvgBackend

impl<'a, DB: DrawingBackend> DrawBackend for PlottersAdapter<'a, DB>