src/lib/ai.rs

@@ -1,67 +1,108 @@
 use crate::lib::entity::{Ant, Egg, Queen};
-use crate::lib::point::{astar, Point};
+use crate::lib::point::{Direction, Point};
 use crate::lib::screen::{BoardCommand, Screen};
-use crate::lib::world::World;
+use crate::lib::world::{Pheremone, World};
 use rand::prelude::SliceRandom;
 use rand::thread_rng;
+use std::iter::zip;
 
 pub trait AI {
     fn step(&mut self, b: &Screen, w: &mut World) -> BoardCommand;
-    fn plan(&mut self, w: &World) {}
+    fn plan(&mut self, b: &Screen, w: &mut World) -> BoardCommand {
+        BoardCommand::Noop
+    }
 }
 
 #[derive(Clone, Debug)]
 pub enum AIGoal {
     Seek,
-    //Pickup(Point),
-    //Drop(),
-    Idle,
+    Return,
 }
 
 impl AI for Ant {
-    fn plan(&mut self, w: &World) {
-        // check last part of plan
-        if let Some(goal) = self.plan.last() {
-            match goal {
+    fn plan(&mut self, b: &Screen, w: &mut World) -> BoardCommand {
+        match self.goal {
             AIGoal::Seek => {
                 // if we reach food, we change state
                 if w.food.contains(&self.pos) {
-                        self.plan.pop();
+                    for p in &self.history {
+                        w.drop_pheremone(&p, &self.goal);
                     }
+                    self.history.clear();
+                    self.cw();
+                    self.cw();
+                    self.goal = AIGoal::Return;
+                } 
+                BoardCommand::Noop
+            }
+            AIGoal::Return => {
+                if self.pos == b.center {
+                    for p in &self.history {
+                        w.drop_pheremone(&p, &self.goal);
+                    }
+                    self.history.clear();
+                    self.cw();
+                    self.cw();
+                    self.goal = AIGoal::Seek;
+                    return BoardCommand::SpawnAnt
+                } else {
+                    BoardCommand::Noop
                 }
-                AIGoal::Idle => {}
             }
         }
     }
 
-    // return the next move for this ant
     fn step(&mut self, b: &Screen, w: &mut World) -> BoardCommand {
-        let goal = match self.plan.last() {
-            Some(g) => g,
-            None => &AIGoal::Idle,
+
+        let valid = vec![
+            (self.dir, self.dir.relative_point(&self.pos)),
+            (self.dir.ccw(), self.dir.ccw().relative_point(&self.pos)),
+            (self.dir.cw(), self.dir.cw().relative_point(&self.pos)),
+        ];
+
+        let ph: Vec<Pheremone> = valid
+            .iter()
+            .map(|(_, pnt)| { 
+                let op = w.cleared.get(pnt);
+                match op {
+                    Some(ph) => ph.clone(),
+                    None => {
+                        w.cleared.insert(pnt.clone(), Pheremone::new());
+                        w.cleared.get(pnt).unwrap().clone()
+                    }
+                }
+            })
+            .collect();
+
+        let ph_fn = match self.goal {
+            AIGoal::Seek => |ph: &Pheremone| ph.food,
+            AIGoal::Return => |ph: &Pheremone| ph.home,
         };
 
-        let valid = w.get_valid_movements(&self.pos, b, true);
+        let r: f32 = rand::random();
+        
+        let mut dir = &valid[0].0;
+        if r < 0.2 || ph.len() == 0 {
             let mut rng = thread_rng();
-        let choice = valid.choose(&mut rng).cloned();
-        
-        if !choice.is_none() {
-            let pos = choice.unwrap();
-            if w.cleared.contains(&pos) {
-                self.pos = pos;
+            let choice = valid.choose(&mut rng).unwrap();
+            dir = &choice.0;
         } else {
-                
-                match goal {
-                AIGoal::Seek => {
-                    if w.is_safe_to_dig(&pos, &b) {
-                        w.clear(pos);
-                    }
-                },
-                AIGoal::Idle => {}
+            let mut greatest = &ph[0];
+            for (tup, p) in zip(&valid, &ph) {
+                if ph_fn(p) > ph_fn(greatest) {
+                    greatest = p;
+                    dir = &tup.0;
                 }
             }
         }
     
+        if dir == &self.dir {
+            self.forward(w,b);
+        } else if dir == &self.dir.cw() {
+            self.cw();
+        } else if dir == &self.dir.ccw() {
+            self.ccw();
+        } 
         BoardCommand::Noop
     }
 }
@@ -79,14 +120,14 @@ impl AI for Egg {
 
 impl AI for Queen {
     fn step(&mut self, b: &Screen, w: &mut World) -> BoardCommand {
-        let valid: Vec<Point> = w.get_valid_movements(&self.pos, b, false);
+        let valid: Vec<Point> = self.pos.get_neighbors();
         let mut rng = thread_rng();
 
         let choice = valid.choose(&mut rng).cloned();
 
         if !choice.is_none() {
             let pos = choice.unwrap();
-            if w.cleared.contains(&pos) {
+            if w.is_cleared(&pos) {
                 // choose between laying an egg and moving
                 if self.egg_count < 3 {
                     self.egg_count += 1;

src/lib/entity.rs

@@ -1,10 +1,10 @@
 use crate::lib::ai::{AIGoal, AI};
-use crate::lib::point::Point;
+use crate::lib::point::{Direction, Point};
 use crate::lib::screen::{BoardCommand, Screen};
 use crate::lib::world::World;
 use rand::Rng;
 
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 
 use ncurses::*;
 
@@ -40,7 +40,9 @@ impl_downcast!(Renderable);
 pub struct Ant {
     pub pos: Point,
     pub id: u32,
-    pub plan: Vec<AIGoal>,
+    pub goal: AIGoal,
+    pub dir: Direction,
+    pub history: HashSet<Point>,
 }
 
 impl Ant {
@@ -48,10 +50,36 @@ impl Ant {
         Ant {
             pos: Point(x, y),
             id: 0,
-            plan: vec![],
+            goal: AIGoal::Seek,
+            dir: Direction::Up,
+            history: HashSet::new(),
         }
     }
+
+    pub fn forward(&mut self, w: &mut World, b: &Screen) {
+        let target = self.dir.relative_point(&self.pos);
+        if b.is_in_bounds(&target) {
+            if w.is_cleared(&self.pos) {
+                self.history.insert(self.pos);
+                self.pos = target;
+            } else {
+                w.clear(target);
             }
+        } else {
+            self.cw();
+            self.cw();
+        }
+    }
+
+    pub fn ccw(&mut self) {
+        self.dir = self.dir.ccw();
+    }
+
+    pub fn cw(&mut self) {
+        self.dir = self.dir.cw();
+    }
+}
+
 impl_entity!(Ant);
 impl_entity!(Food);
 impl_entity!(FoodGenerator);
@@ -60,14 +88,27 @@ impl_entity!(Queen);
 
 impl Renderable for Ant {
     fn representation(&self) -> &str {
-        "o"
+        match self.dir {
+            Direction::Up => "^",
+            Direction::Down => "v",
+            Direction::Right => ">",
+            Direction::Left => "<",
+        }
     }
     fn before_render(&self) {
         attron(A_BOLD());
+        match self.goal {
+            AIGoal::Return => attron(A_UNDERLINE()),
+            AIGoal::Seek => 0,
+        };
     }
 
     fn after_render(&self) {
         attroff(A_BOLD());
+        match self.goal {
+            AIGoal::Return => attroff(A_UNDERLINE()),
+            AIGoal::Seek => 0,
+        };
     }
 }
 
@@ -188,8 +229,11 @@ impl Food {
 
 impl AI for Food {
     fn step(&mut self, b: &Screen, w: &mut World) -> BoardCommand {
-        // perhaps check if we're in target?
-        // implement drag logic?
+        for n in self.pos.get_neighbors() {
+            w.drop_pheremone(&n, &AIGoal::Seek);
+        }
+        w.drop_pheremone(&self.pos, &AIGoal::Seek);
+
         BoardCommand::Noop
     }
 }
@@ -206,12 +250,17 @@ pub struct FoodGenerator {
     timer: u32,
     pos: Point,
     id: u32,
-    counter: u32
+    counter: u32,
 }
 
 impl FoodGenerator {
     pub fn new() -> FoodGenerator {
-        FoodGenerator { timer: 0, id: 0, pos: Point(0,0), counter: 0 }
+        FoodGenerator {
+            timer: 0,
+            id: 0,
+            pos: Point(0, 0),
+            counter: 0,
+        }
     }
 }
 

src/lib/point.rs

@@ -14,29 +14,10 @@ impl Point {
         Point(self.0 - 1, self.1)
     }
 
-    pub fn is_below(&self, other: Point) -> bool {
-        other.down() == *self
-    }
-
     pub fn right(&self) -> Point {
         Point(self.0 + 1, self.1)
     }
 
-    pub fn uldiag(&self) -> Point {
-        Point(self.0 - 1, self.1 - 1)
-    }
-
-    pub fn bldiag(&self) -> Point {
-        Point(self.0 + 1, self.1 - 1)
-    }
-
-    pub fn brdiag(&self) -> Point {
-        Point(self.0 + 1, self.1 + 1)
-    }
-
-    pub fn urdiag(&self) -> Point {
-        Point(self.0 - 1, self.1 + 1)
-    }
     // y values are reversed in ncurses
     pub fn down(&self) -> Point {
         Point(self.0, self.1 + 1)
@@ -47,111 +28,45 @@ impl Point {
     }
 }
 
-fn manhattan(c1: &Point, c2: &Point) -> i32 {
-    return (c2.0 - c1.0).abs() + (c2.1 - c1.1).abs();
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub enum Direction {
+    Up = 0,
+    Right = 1,
+    Down = 2,
+    Left = 3,
 }
 
-fn weigh_point(w: &World, p: &Point) -> i32 {
-    if w.is_cleared(p) {
-        3
+impl Direction {
+    pub fn from_u8(v: u8) -> Direction {
+        match v {
+            0 => Direction::Up,
+            1 => Direction::Right,
+            2 => Direction::Down,
+            3 => Direction::Left,
+            _ => panic!("Shouldn't happen")
+        }
+    }
+
+    pub fn cw(&self) -> Direction {
+        let val = *self as u8;
+        Direction::from_u8((val + 1) % 4)
+    }
+
+    pub fn ccw(&self) -> Direction {
+        let val = *self as u8;
+        if val == 0 {
+            Direction::Left
         } else {
-        15
+            Direction::from_u8(val - 1)
         }
     }
 
-pub struct PathNotFoundError;
-
-pub fn astar(start: &Point, goal: &Point, w: Option<&World>, s: Option<&Screen>) -> Result<Vec<Point>, PathNotFoundError> {
-    let mut open_set: HashSet<Point> = HashSet::new();
-    open_set.insert(*start);
-
-    let mut came_from: HashMap<Point, Point> = HashMap::new();
-
-    let mut gscore: HashMap<Point, i32> = HashMap::new();
-    gscore.insert(*start, 0);
-
-    let mut fscore: HashMap<Point, i32> = HashMap::new();
-    fscore.insert(*start, manhattan(&start, &goal));
-
-    let mut answer = Vec::new();
-
-    let mut current: Point = *start;
-    while !open_set.is_empty() {
-        let mut min_score = i32::MAX;
-        for c in open_set.iter() {
-            let val = fscore[c];
-            current = if val < min_score { c.clone() } else { current };
-            min_score = if val < min_score { val } else { min_score };
-        }
-
-        if current == *goal {
-            answer.push(current.clone());
-            while came_from.contains_key(&current) {
-                current = came_from[&current].clone();
-                if current != *start {
-                    answer.push(current.clone());
-                }
-            }
-            return Ok(answer);
-        }
-
-        open_set.remove(&current);
-
-        let current_gscore = gscore[&current];
-
-        let all_neighbors: Vec<Point> = match w {
-            Some(w) => current
-                .get_neighbors()
-                .iter()
-                .filter(|p| w.is_valid_movement(&current, p, s.unwrap()))
-                .map(|e| e.clone())
-                .collect(),
-            None => current.get_neighbors(),
-        };
-
-        for neighbor in all_neighbors.iter() {
-            let neighbor_score = if gscore.contains_key(&neighbor) {
-                gscore[&neighbor]
-            } else {
-                i32::MAX
-            };
-
-            let weight = match w {
-                Some(w) => weigh_point(&w, neighbor),
-                None => 1,
-            };
-
-            let score = current_gscore + weight;
-
-            if score < neighbor_score {
-                gscore.insert(neighbor.clone(), score);
-                fscore.insert(neighbor.clone(), score + manhattan(&neighbor, &goal));
-                came_from.insert(neighbor.clone(), current.clone());
-                open_set.insert(neighbor.clone());
+    pub fn relative_point(&self, p: &Point) -> Point {
+        match self {
+            Direction::Up => p.up(),
+            Direction::Left => p.left(),
+            Direction::Right => p.right(),
+            Direction::Down => p.down(),
         }
     }
 }
-
-    Err(PathNotFoundError)
-}
-
-#[test]
-fn test_astar() {
-    let start = Point(0, 0);
-
-    let goal = Point(10, 10);
-    let answers = astar(&start, &goal, None, None);
-    
-    match answers {
-        Ok(ans) => {
-            for a in ans.iter() {
-                println!("{:?}", &a);
-            }     
-        },
-        Err(_) => {
-            panic!("Path not found. That shouldn't happen!")
-        }
-    }
-
-    
-}

src/lib/screen.rs

@@ -11,6 +11,8 @@ use ncurses::*;
 pub fn init_screen() -> Screen {
     initscr();
 
+    start_color();
+    init_pair(0, 0, 1);
     /* Invisible cursor. */
     curs_set(CURSOR_VISIBILITY::CURSOR_INVISIBLE);
 
@@ -81,5 +83,6 @@ pub enum BoardCommand {
     LayEgg(Point, u32),
     SpawnFood(Point),
     Hatch(u32, u32),
+    SpawnAnt,
     Noop,
 }

src/lib/world.rs

@@ -1,24 +1,46 @@
+use crate::lib::ai::AIGoal;
 use crate::lib::entity::{Ant, Egg, Entities, Food, Queen};
-use crate::lib::point::{astar, Point};
+use crate::lib::point::Point;
 use crate::lib::screen::{BoardCommand, Screen};
-use std::collections::HashSet;
+use std::collections::{HashMap, HashSet};
 
 #[derive(Clone)]
 pub struct World {
-    pub cleared: HashSet<Point>,
+    pub cleared: HashMap<Point, Pheremone>,
     pub food: HashSet<Point>,
 }
 
+#[derive(Clone, PartialEq, PartialOrd, Debug)]
+pub struct Pheremone {
+    pub home: u32,
+    pub food: u32,
+}
+
+impl Pheremone {
+    pub fn new() -> Pheremone {
+        Pheremone { home: 0, food: 0 }
+    }
+
+    pub fn decay(&mut self) {
+        if self.home > 0 {
+            self.home -= 1;
+        }
+        if self.food > 0 {
+            self.food -= 1;
+        }
+    }
+}
+
 impl World {
     pub fn new() -> World {
         World {
-            cleared: HashSet::new(),
+            cleared: HashMap::new(),
             food: HashSet::new(),
         }
     }
 
     pub fn clear(&mut self, pos: Point) {
-        self.cleared.insert(pos);
+        self.cleared.insert(pos, Pheremone::new());
     }
 
     pub fn create_chamber(&mut self, center: Point, radius: i32) {
@@ -32,67 +54,30 @@ impl World {
         }
     }
 
-    pub fn is_valid_movement(&self, current: &Point, target: &Point, b: &Screen) -> bool {
-        // should allow down movements always
-
-        let safe = target.is_below(*current)
-            || (!self.cleared.contains(&target.down())
-                || !self.cleared.contains(&target.left())
-                || !self.cleared.contains(&target.right())
-                || !self.cleared.contains(&target.bldiag())
-                || !self.cleared.contains(&target.uldiag())
-                || !self.cleared.contains(&target.brdiag())
-                || !self.cleared.contains(&target.urdiag()));
-
-        // of course, its only a valid move if you can walk there!
-        b.is_in_bounds(target) && self.cleared.contains(target) && safe
-    }
-
     pub fn is_cleared(&self, pos: &Point) -> bool {
-        self.cleared.contains(pos)
+        self.cleared.contains_key(pos)
     }
 
-    pub fn is_safe_to_dig(&self, target: &Point, b: &Screen) -> bool {
-        let mut hypothetical_world = self.clone();
-        hypothetical_world.clear(*target);
-        let result = astar(target, &b.center, Some(&hypothetical_world), Some(b));
-        b.is_in_bounds(target) && result.is_ok()
+    pub fn drop_pheremone(&mut self, pos: &Point, state: &AIGoal) {
+        let op = self.cleared.get_mut(&pos);
+
+        let ph = match op {
+            Some(p) => p,
+            None => {
+                self.cleared.insert(*pos, Pheremone::new());
+                self.cleared.get_mut(pos).unwrap()
             }
+        };
 
-    pub fn get_diggable(&self, b: &Screen, pos: &Point) -> Vec<Point> {
-        let moves = b.get_valid_movements(pos);
-        moves
-            .iter()
-            .filter(|p| !self.is_cleared(p))
-            .map(|p| p.clone())
-            .collect()
+        match state {
+            AIGoal::Seek => ph.home += 1,
+            AIGoal::Return => ph.food += 1,
         }
-
-    pub fn get_valid_movements(
-        &self,
-        pos: &Point,
-        b: &Screen,
-        return_diggables: bool,
-    ) -> Vec<Point> {
-        let moves = b.get_valid_movements(pos);
-        let mut ans: Vec<Point> = moves
-            .iter()
-            .filter(|p| self.is_valid_movement(pos, p, b))
-            .map(|p| p.clone())
-            .collect();
-
-        if return_diggables {
-            let digs = self.get_diggable(b, pos);
-            ans.extend(digs);
-        }
-
-        ans
-
     }
 }
 
 pub fn render(e: &Entities, w: &World, b: &Screen) {
-    for c in w.cleared.iter() {
+    for c in w.cleared.keys() {
         b.render(c, "x");
     }
 
@@ -101,18 +86,19 @@ pub fn render(e: &Entities, w: &World, b: &Screen) {
     }
 }
 
-pub fn simulate(e: &mut Entities, w: &mut World, b: &mut Screen) {
-    let cmds: Vec<BoardCommand> = e
-        .data
-        .values_mut()
-        .map(|a| {
-            a.plan(w);
-            a.step(b, w)
-        })
-        .collect();
+pub fn simulate(e: &mut Entities, w: &mut World, b: &mut Screen, step: u32) {
+    let plan_cmds: Vec<BoardCommand> = e.data.values_mut().map(|a| a.plan(b, w)).collect();
+
+    let mut cmds: Vec<BoardCommand> = e.data.values_mut().map(|a| a.step(b, w)).collect();
+
+    cmds.extend(plan_cmds);
 
     for cmd in cmds {
         match cmd {
+            BoardCommand::SpawnAnt => {
+                let ant = Ant::new(b.center.0, b.center.1);
+                e.add_entity(&ant);
+            }
             BoardCommand::Dig(pos) => {
                 w.clear(pos);
             }
@@ -138,4 +124,16 @@ pub fn simulate(e: &mut Entities, w: &mut World, b: &mut Screen) {
             BoardCommand::Noop => {}
         }
     }
+
+    for n in b.center.get_neighbors() {
+        w.drop_pheremone(&n, &AIGoal::Return);
+    }
+    w.drop_pheremone(&b.center, &AIGoal::Return);
+
+    // decay all pheremones by some amount
+    if step % 60 == 0 {
+        for ph in w.cleared.values_mut() {
+            ph.decay();
+        }
+    }
 }

src/main.rs

@@ -7,17 +7,17 @@ use std::thread::sleep;
 use std::time;
 
 mod lib {
+    pub mod ai;
+    pub mod entity;
     pub mod point;
     pub mod screen;
     pub mod world;
-    pub mod entity;
-    pub mod ai;
 }
 
+use lib::entity::{Ant, Entities, FoodGenerator};
 use lib::point::Point;
 use lib::screen::init_screen;
-use lib::world::{World, simulate, render};
-use lib::entity::{Entities, Ant, FoodGenerator};
+use lib::world::{render, simulate, World};
 
 fn main() {
     let mut board = init_screen();
@@ -31,18 +31,22 @@ fn main() {
     let fg = FoodGenerator::new();
     entities.add_entity(&fg);
 
+    for _ in 0..5 {
         let mut a = Ant::new(board.center.0, board.center.1);
-    a.plan.push(lib::ai::AIGoal::Seek);
+        a.goal = lib::ai::AIGoal::Seek;
         entities.add_entity(&a);
+    }
 
     world.create_chamber(Point(board.center.0, board.center.1), 3);
 
+    let mut t = 0;
     loop {
         // TODO: add way to break out of the loop by hitting a random key
-        simulate(&mut entities, &mut world, &mut board);
+        simulate(&mut entities, &mut world, &mut board, t);
         render(&entities, &world, &board);
         sleep(time::Duration::from_millis(100));
         refresh();
+        t += 1;
     }
     endwin();
 }

tests/ai_test.rs

@@ -23,15 +23,15 @@ fn test_reach_astar() {
 
     let a = entities.data.get_mut(&id).unwrap();
     let ant: &mut Ant = a.downcast_mut::<Ant>().unwrap();
-    ant.plan.push(AIGoal::Reach(Point(0, 0)));
+    /*ant.plan.push(AIGoal::Reach(Point(0, 0)));
     ant.plan.push(AIGoal::Reach(Point(20, 20)));
     ant.plan.push(AIGoal::Reach(Point(0, 0)));
-    ant.plan.push(AIGoal::Reach(Point(20, 20)));
+    ant.plan.push(AIGoal::Reach(Point(20, 20)));*/
 
     // craps out... need to make sure unwrap() is safe
-    for _ in 0..420 {
+    for t in 0..420 {
         // TODO: add way to break out of the loop by hitting a random key
-        simulate(&mut entities, &mut world, &mut board);
+        simulate(&mut entities, &mut world, &mut board, t);
         render(&entities, &world, &board);
         sleep(time::Duration::from_millis(100));
         refresh();

tests/entity_test.rs

@@ -15,9 +15,9 @@ fn test_foodgen() {
     let fg = FoodGenerator::new();
     entities.add_entity(&fg);
 
-    for _ in 0..60 {
+    for t in 0..60 {
         // TODO: add way to break out of the loop by hitting a random key
-        simulate(&mut entities, &mut world, &mut board);
+        simulate(&mut entities, &mut world, &mut board, t);
         render(&entities, &world, &board);
         sleep(time::Duration::from_millis(100));
         refresh();