Method transform_position

src/transform.rs:206–221

Convert a value into a normalized `[0, 1]` position along an axis. Data-coordinate transforms use `axis_range` as raw data coordinates. Axes-coordinate transforms already store normalized positions.

(
        &self,
        pos: f64,
        axis_scale: AxisScale,
        axis_range: [f64; 2],
    )

    /// Data-coordinate transforms use `axis_range` as raw data coordinates.
    /// Axes-coordinate transforms already store normalized positions.
    pub fn transform_position(
        &self,
        pos: f64,
        axis_scale: AxisScale,
        axis_range: [f64; 2],
    ) -> Option<f64> {
        if self.coordinate_system == CoordinateSystem::Axes {
            return self.transform_value(pos);
        }

        let pos = self.transform_data(pos, axis_scale)?;
        let min = self.transform_data(axis_range[0], axis_scale)?;
        let max = self.transform_data(axis_range[1], axis_scale)?;
        let span = max - min;
        (span.is_finite() && span.abs() > f64::EPSILON).then_some((pos - min) / span)
    }

    pub(crate) fn uses_axes_coordinates(&self) -> bool {
        self.coordinate_system == CoordinateSystem::Axes