roguelike-game/src/visibility_system.rs

45 lines
1.5 KiB
Rust

use crate::{Map, Player, Position, Viewshed};
use rltk::{field_of_view, Point};
use specs::prelude::*;
pub struct VisibilitySystem {}
impl<'a> System<'a> for VisibilitySystem {
type SystemData = (
WriteExpect<'a, Map>,
Entities<'a>,
WriteStorage<'a, Viewshed>,
WriteStorage<'a, Position>,
ReadStorage<'a, Player>,
);
fn run(&mut self, data: Self::SystemData) {
let (mut map, entities, mut viewshed, pos, player) = data;
for (ent, viewshed, pos) in (&entities, &mut viewshed, &pos).join() {
if viewshed.dirty {
viewshed.dirty = false;
viewshed.visible_tiles.clear();
viewshed.visible_tiles =
field_of_view(Point::new(pos.x, pos.y), viewshed.range, &*map);
viewshed
.visible_tiles
.retain(|p| p.x >= 0 && p.x < map.width && p.y >= 0 && p.y < map.height);
// if this is the player, reveal what they can see
let _p: Option<&Player> = player.get(ent);
if let Some(_p) = _p {
for t in map.visible_tiles.iter_mut() {
*t = false
}
for vis in viewshed.visible_tiles.iter() {
let idx = map.xy_idx(vis.x, vis.y);
map.revealed_tiles[idx] = true;
map.visible_tiles[idx] = true;
}
}
}
}
}
}