Method write

tools/streamline.rs:225–257

(&self, writer: &mut W)

    }

    fn write<W>(&self, writer: &mut W) -> eyre::Result<()>
    where
        W: std::io::Write,
    {
        let min_i = self.x2i(self.min_x);
        let max_i = self.x2i(self.max_x);
        let min_j = self.y2j(self.min_y);
        let max_j = self.y2j(self.max_y);

        let is = min_i..=max_i;
        let js = min_j..=max_j;
        let vectors = js.flat_map(|j| {
            is.clone().map(move |i| {
                let x1 = self.i2x(i);
                let y1 = self.j2y(j);

                let vector = (self.function)(x1, y1);

                // Vector field visualizations don't look good if the vectors use the same scale as the
                // uniform grid they're drawn on. So we scale by the delta-h.
                let dx = vector.0 * self.stride;
                let dy = vector.1 * self.stride;

                let x2 = x1 + dx;
                let y2 = y1 + dy;

                let line = Line::new(Coord { x: x1, y: y1 }, Coord { x: x2, y: y2 });
                Geometry::Line(line)
            })
        });

        write_geometries(writer, vectors)
    }
}

#[allow(clippy::too_many_arguments)]