line_of_sight

A crate for finding the line of sight on a 2D grid.

Example

use line_of_sight::ShadowMap;
use line_of_sight::BLOCK;
use line_of_sight::PLAYER;

// create a 16x17 line of sight map with empty cells by default
let mut map = ShadowMap::new_with_empty_cells(16, 17);

// add some obstacles
let obstacles = vec![
    (3, 3),
    (4, 3),
    (5, 3),
    (8, 7),
    (8, 5),
    (6, 9),
    (6, 10),
    (6, 11),
    (7, 11),
    (7, 10),
    (7, 9),
];

for obstacle in obstacles {
    map.set(obstacle.0, obstacle.1, BLOCK);
}

// set the center to be (4, 5)
let center = (4.0, 5.0);

// fully scan the map in the 20 unit radius (in 4 directions. Use `scan_arc` to only scan in 1 direction)
map.full_scan(center, 20.0);

// set (4, 5) to be the "player cell" for visual purposes
map.set(4, 5, PLAYER);
map.show();

Result

[2, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2]
[2, 2, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2]
[2, 2, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2]
[2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0]
[2, 2, 2, 2, 3, 2, 2, 2, 1, 0, 0, 0, 0, 0, 0, 0]
[2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0]
[2, 2, 2, 2, 2, 2, 2, 2, 1, 0, 2, 2, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 0, 0, 0, 0, 2]
[2, 2, 2, 2, 2, 2, 1, 1, 0, 2, 2, 2, 2, 0, 0, 0]
[2, 2, 2, 2, 2, 2, 1, 1, 0, 0, 2, 2, 2, 2, 0, 0]
[2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 2, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 2, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 2, 2, 2]
[2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 2, 2]

Explanation

• 0 -- unreachable cells
• 1 -- obstacles
• 2 -- reachable cells
• 3 -- center (optional; visual purpose only)

Graphical result

Explanation

• white cells -- reachable cells
• grey cells -- unreachable cells
• blue cells -- obstacles
• orange cell -- center