event::EventType,

    surface::Surface,

    pixels::{

        PixelFormatEnum, Color

    }

use integral_geometry::Point;

    thread_rng, RngCore, Rng,

    distributions::uniform::SampleUniform

fn fill_pixels(pixels: &mut [u8], land: &Land2D<u32>) {

    for (surf_row, land_row) in pixels.chunks_mut(land.width() * 4).zip(land.rows()) {

        for (surf_pixel, land_pixel) in surf_row.chunks_mut(4).zip(land_row) {

            if let [b, g, r, a] = surf_pixel {

                *a = 255; *r = *land_pixel as u8;

            }

        }

    }

}

fn fill_texture(surface: &mut Surface, land: &Land2D<u32>) {

    if surface.must_lock() {

        surface.with_lock_mut(|data| fill_pixels(data, land));

    } else {

        surface.without_lock_mut().map(|data| fill_pixels(data, land));

    }

}

fn rnd<T: Default + SampleUniform + Ord>(max: T) -> T {

    thread_rng().gen_range(T::default(), max)

}

const WIDTH: u32 = 512;

const HEIGHT: u32 = 512;

    let window = video.window("Theme Editor", WIDTH, HEIGHT)

    let mut land_surf = Surface::new(WIDTH, HEIGHT, PixelFormatEnum::ARGB8888).unwrap();

    fn point() -> Point {

        Point::new(rnd(WIDTH as i32), rnd(HEIGHT as i32))

    }

    let mut land = Land2D::new(WIDTH as usize, HEIGHT as usize, 0);

    for i in 0..64 {

        land.draw_thick_line(point(), point(), rnd(5), u32::max_value());

    }

    fill_texture(&mut land_surf, &land);

    let mut win_surf = window.surface(&pump).unwrap();

    let win_rect = win_surf.rect();

    land_surf.blit(land_surf.rect(), &mut win_surf, win_rect).unwrap();

    win_surf.update_window();

        }

}