roguelike-game/src/monster_ai_system.rs
2021-10-29 15:15:22 -04:00

75 lines
2.3 KiB
Rust

use crate::{Map, Monster, Position, RunState, Viewshed, WantsToMelee};
use rltk::Point;
use specs::prelude::*;
pub struct MonsterAI {}
impl<'a> System<'a> for MonsterAI {
#[allow(clippy::type_complexity)]
type SystemData = (
WriteExpect<'a, Map>,
ReadExpect<'a, Point>,
ReadExpect<'a, Entity>,
ReadExpect<'a, RunState>,
Entities<'a>,
WriteStorage<'a, Viewshed>,
ReadStorage<'a, Monster>,
WriteStorage<'a, Position>,
WriteStorage<'a, WantsToMelee>,
);
fn run(&mut self, data: Self::SystemData) {
let (
mut map,
player_pos,
player_entity,
runstate,
entities,
mut viewshed,
monster,
mut position,
mut wants_to_melee,
) = data;
if *runstate != RunState::MonsterTurn {
return;
}
for (entity, mut viewshed, _monster, mut pos) in
(&entities, &mut viewshed, &monster, &mut position).join()
{
let distance =
rltk::DistanceAlg::Pythagoras.distance2d(Point::new(pos.x, pos.y), *player_pos);
if distance < 1.5 {
// Attack goes here
wants_to_melee
.insert(
entity,
WantsToMelee {
target: *player_entity,
},
)
.expect("Unable to insert attack");
} else if viewshed.visible_tiles.contains(&*player_pos) {
let path = rltk::a_star_search(
map.xy_idx(pos.x, pos.y) as i32,
map.xy_idx(player_pos.x, player_pos.y) as i32,
&mut *map,
);
if path.success && path.steps.len() > 1 {
let mut idx = map.xy_idx(pos.x, pos.y);
map.blocked[idx] = false;
pos.x = path.steps[1] as i32 % map.width;
pos.y = path.steps[1] as i32 / map.width;
idx = map.xy_idx(pos.x, pos.y);
map.blocked[idx] = true;
viewshed.dirty = true;
}
}
}
}
}