Function simulate_coordinate

tools/streamline.rs:320–356

(
    original: Coord,
    field: &VectorField,
    timestep: f64,
    num_timesteps: usize,
    record_streamlines: bool,
)

}

fn simulate_coordinate(
    original: Coord,
    field: &VectorField,
    timestep: f64,
    num_timesteps: usize,
    record_streamlines: bool,
) -> (AffineTransform, LineString) {
    let mut streamline = Vec::with_capacity(if record_streamlines { num_timesteps } else { 0 });
    let mut current = original;
    if record_streamlines {
        streamline.push(current);
    }
    for _ in 0..num_timesteps {
        if current.x > field.max_x
            || current.x < field.min_x
            || current.y > field.max_y
            || current.y < field.min_y
        {
            break;
        }

        let current_vector = (field.function)(current.x, current.y);

        current.x += timestep * current_vector.0;
        current.y += timestep * current_vector.1;

        if record_streamlines {
            streamline.push(current);
        }
    }

    // TODO: Keep track of the initial and final coordinate orientations
    let offset = current - original;
    let transform = AffineTransform::translate(offset.x, offset.y);

    (transform, LineString::new(streamline))
}

fn simulate_rigid_geometry(
    mut geometry: Geometry,