AI perfect chance, rendering with proportions instead of absolute pixel values

src/comp/mod.rs

@@ -1,12 +1,15 @@
 //! AI player logic
 
 use indextree::{Arena, Node, NodeId, NodeEdge};
+
+use rand::prelude::*;
 use rand::seq::SliceRandom;
 
 extern crate wasm_bindgen;
 // use wasm_bindgen::prelude::*;
 
 use crate::log;
+use crate::log_error;
 
 use crate::board::{Board, BrdIdx};
 use crate::board::enums::{MoveType, Moveable, Team};
@@ -63,13 +66,15 @@ pub struct Computer {
     pub search_depth: usize,
     pub team: Team,
     pub last_node_count: usize,
+    pub perfect_chance: f64,
 }
 
 impl Computer {
-    pub fn new(search_depth: usize, team: Team) -> Computer {
+    pub fn new(search_depth: usize, team: Team, perfect_chance: f64) -> Computer {
         Computer {
             search_depth,
             team,
+            perfect_chance,
             last_node_count: 0,
         }
     }
@@ -333,49 +338,88 @@ impl Computer {
             .expect("No node returned for node id")
             .get(); // get BoardNode from Node
 
-        // when boards have equal scores, store for shuffling and selection
-        let mut equal_scores = Vec::with_capacity(10);
+        // node ids of available next moves
+        let possible_moves: Vec<NodeId> = root_node.children(&tree).collect();
+
+        if possible_moves.len() == 0 {
+            return None;
+        }
 
         // DEBUG
         #[cfg(feature = "debug_logs")]
         {
             log!("Current root score: {}", root_board_node.score);
-            let scores: Vec<NodeId> = root_node
-                .children(&tree)
-                .collect();
-            let scores: Vec<isize> = scores
-                .into_iter()
-                .map(|n| tree.get(n).unwrap().get().score)
+            let scores: Vec<isize> = possible_moves
+                .iter()
+                .map(|n| tree.get(*n).unwrap().get().score)
                 .collect();
             log!("Next boards scores: {:?}", scores);
         }
 
-        // search through root node's children for the same score
-        for n in root_node.children(&tree) {
+        let mut rng = rand::thread_rng();
+        // random number to compare against threshold
+        let perfect_num: f64 = rng.gen();
 
-            // get each board
-            let iter_board_node = tree
-                .get(n) // get Node
-                .expect("No node returned for node id")
-                .get(); // get BoardNode from Node
+        // make perfect move
+        if perfect_num < self.perfect_chance {
+            #[cfg(feature = "debug_logs")]
+            log!("Making perfect move");
 
-            if root_board_node.score == iter_board_node.score {
-                equal_scores.push(iter_board_node);
-                // return Some(iter_board_node.board.clone());
+            // get boards of equal score that are perfect for the given player
+            let possible_perfect_moves: Vec<&BoardNode> = possible_moves
+                .iter()
+                .map(
+                    // get immutable references to BoardNodes for possible moves
+                    |n| tree
+                        .get(*n) // get Node using NodeID
+                        .expect("Unable to get perfect move data from tree node")
+                        .get() // get *BoardNode from Node
+                )
+                .filter(
+                    // filter for only scores of root node which are perfect moves
+                    |b| b.score == root_board_node.score
+                )
+                .collect();
+
+            // weird error, no child nodes have same score as root node
+            // this is odd because the root nodes score is either the max or min of it's children
+            if possible_perfect_moves.len() == 0 {
+                log_error!("No next moves matched the score of the root node, picking randomly instead");
+                
+                Some(Computer::random_choice(&tree, possible_moves, &mut rng))
+            }
+            // only one possible move, use that
+            else if possible_perfect_moves.len() == 1 {
+                Some(possible_perfect_moves[0].board.clone())
+            }
+            // more than one possible perfect move to make, choose one randomly
+            else {
+                Some(
+                    possible_perfect_moves
+                        .choose(&mut rng) // random choice
+                        .unwrap() // unwrap Option
+                        .board
+                        .clone()
+                )
             }
         } 
+        // get random move
+        else {
+            #[cfg(feature = "debug_logs")]
+            log!("Making random move");
 
-        if equal_scores.len() == 0 {
-            None
-        } else if equal_scores.len() == 1 {
-            Some(equal_scores[0].board.clone())
-        } else {
-            Some(equal_scores
-                .choose(&mut rand::thread_rng())
-                .unwrap()
-                .board
-                .clone()
-            )
+            Some(Computer::random_choice(&tree, possible_moves, &mut rng))
         }
     }
+
+    /// Get a random board from possible node IDs and associated tree
+    fn random_choice(tree: &Arena<BoardNode>, possible_moves: Vec<NodeId>, rng: &mut ThreadRng) -> Board {
+        let chosen_move = possible_moves.choose(rng).unwrap();
+        tree
+            .get(*chosen_move)
+            .expect("Unable to get random move data from tree node")
+            .get()
+            .board
+            .clone()
+    }
 }

src/comp/tests.rs

@@ -4,7 +4,7 @@ use wasm_bindgen_test::*;
 
 use crate::board::Square;
 use crate::board::enums::Strength::*;
-use crate::log;
+// use crate::log;
 
 // use Team::*;
 
@@ -25,7 +25,7 @@ fn available_moves() {
     // _ . _
 
     let mut brd = Board::new(3, 2, White);
-    let comp = Computer::new(3, White);
+    let comp = Computer::new(3, White, 0.5);
 
     // log!("{}", brd);
 
@@ -50,7 +50,7 @@ fn available_moves_jumps() {
     // _ . _ .
     
     let mut brd = Board::new(4, 4, White);
-    let comp = Computer::new(3, White);
+    let comp = Computer::new(3, White, 0.5);
 
     // log!("{}", brd);
 
@@ -71,7 +71,7 @@ fn available_moves_jumps() {
 #[wasm_bindgen_test]
 fn available_moves_std_brd() {
     let brd = Board::init_game(Board::new(8, 8, White), 3);
-    let comp = Computer::new(3, White);
+    let comp = Computer::new(3, White, 0.5);
 
     // log!("{}", brd);
 
@@ -87,7 +87,7 @@ fn available_moves_std_brd() {
 #[wasm_bindgen_test]
 fn expand_node() {
     let brd = Board::init_game(Board::new(8, 8, White), 3);
-    let mut comp = Computer::new(3, White);
+    let mut comp = Computer::new(3, White, 0.5);
 
     // log!("{}", brd);
 
@@ -106,7 +106,7 @@ fn expand_node() {
 #[wasm_bindgen_test]
 fn expand_layer() {
     let brd = Board::init_game(Board::new(8, 8, White), 3);
-    let mut comp = Computer::new(3, White);
+    let mut comp = Computer::new(3, White, 0.5);
 
     // log!("{}", brd);
 
@@ -123,7 +123,7 @@ fn expand_layer() {
 #[wasm_bindgen_test]
 fn leaf_nodes() {
     let brd = Board::init_game(Board::new(8, 8, White), 3);
-    let mut comp = Computer::new(3, White);
+    let mut comp = Computer::new(3, White, 0.5);
 
     let mut tree = Arena::new(); 
     let id = tree.new_node(BoardNode::brd(brd));
@@ -160,7 +160,7 @@ fn insert_scores_all_take() {
     brd.set_cell(brd.cell_idx(BrdIdx::from(1, 4)), Square::pc(White, Man));
     brd.set_cell(brd.cell_idx(BrdIdx::from(2, 1)), Square::pc(Black, Man));
     brd.set_cell(brd.cell_idx(BrdIdx::from(2, 3)), Square::pc(Black, Man));
-    let mut comp = Computer::new(1, White);
+    let mut comp = Computer::new(1, White, 0.5);
 
     // log!("{}", brd);
 
@@ -203,7 +203,7 @@ fn insert_scores_one_take() {
     brd.set_cell(brd.cell_idx(BrdIdx::from(1, 4)), Square::pc(White, Man));
     brd.set_cell(brd.cell_idx(BrdIdx::from(2, 1)), Square::pc(Black, Man));
     // brd.set_cell(brd.cell_idx(BrdIdx::from(2, 3)), Square::pc(Black, Man));
-    let mut comp = Computer::new(1, White);
+    let mut comp = Computer::new(1, White, 0.5);
 
     // log!("{}", brd);
 

src/game/mod.rs

@@ -29,6 +29,7 @@ pub struct Game {
     painter: Option<Painter>,
     search_depth: usize,
     pub last_node_count: usize,
+    pub perfect_chance: f64,
 }
 
 impl Game {
@@ -95,6 +96,7 @@ impl Game {
         self.current.cell(self.current.cell_idx(*idx))
     }
 
+    /// Set tree depth for AI to search to
     pub fn set_search_depth(&mut self, search_depth: usize) {
         self.search_depth = search_depth;
     }
@@ -114,6 +116,11 @@ impl Game {
         }
     }
 
+    /// Set proportion of perfect moves from AI
+    pub fn set_perfect_chance(&mut self, new_chance: f64) {
+        self.perfect_chance = new_chance;
+    }
+
     /// Clear currently selected piece
     pub fn clear_selected(&mut self) {
         self.selected_piece = None;
@@ -180,6 +187,7 @@ impl Game {
             painter: None,
             search_depth,
             last_node_count: 0,
+            perfect_chance: 0.5,
         }
     }
 
@@ -196,6 +204,7 @@ impl Game {
             ),
             search_depth,
             last_node_count: 0,
+            perfect_chance: 0.5,
         }
     }
 
@@ -215,14 +224,22 @@ impl Game {
     /// Create computer, get move from current board and update current board
     pub fn ai_move(&mut self) {
         
-        let mut comp = Computer::new(self.search_depth, self.current.current_turn);
+        let mut comp = Computer::new(self.search_depth, self.current.current_turn, self.perfect_chance);
+
         let new_brd = comp.get_move(self.current.clone());
 
         self.last_node_count = comp.last_node_count;
 
         match new_brd {
             Some(brd) => self.push_new_board(brd),
-            None => panic!("No AI move returned"),
+            None => {
+                log!("No possible moves, re-pushing current board");
+
+                let mut new_brd = self.current.clone();
+                new_brd.current_turn = new_brd.current_turn.opponent();
+
+                self.push_new_board(new_brd);
+            },
         }
     }
 }

src/game/tests.rs

@@ -6,7 +6,7 @@ wasm_bindgen_test_configure!(run_in_browser);
 
 // use crate::board::{Piece};
 use crate::board::enums::Strength::*;
-use crate::board::enums::Team::*;
+// use crate::board::enums::Team::*;
 
 
 #[wasm_bindgen_test]

src/lib.rs

@@ -29,6 +29,12 @@ macro_rules! log {
         web_sys::console::log_1(&format!( $( $t )* ).into());
     }
 }
+#[macro_export]
+macro_rules! log_error {
+    ( $( $t:tt )* ) => {
+        web_sys::console::error_1(&format!( $( $t )* ).into());
+    }
+}
 
 #[wasm_bindgen]
 pub fn init_wasm() {

src/paint.rs

@@ -23,8 +23,8 @@ const BLACK_SQUARE: &str = "#000000";
 
 /// Default hex colour value for outline of black squares
 const SQUARE_OUTLINE: &str = "#9c9c9c";
-/// Line width when outlining black squares
-const OUTLINE_WIDTH: f64 = 3.0;
+/// Line width when outlining black squares as proportion of min cell dimension
+const OUTLINE_WIDTH: f64 = 0.05;
 /// Whether to outline black squares
 const DRAW_OUTLINE: bool = true;
 
@@ -46,10 +46,10 @@ const SELECTED_PIECE_OUTLINE: &str = "#d1cf45";
 const KING_OUTLINE: &str = "#ffea00";
 /// Whether to outline pieces
 const DRAW_PIECE_OUTLINES: bool = true;
-/// Line width for outlining pieces
-const PIECE_OUTLINE_WIDTH: f64 = 6.0;
-/// Margin from square to define piece radius
-const PIECE_MARGIN: f64 = 14.0;
+/// Line width for outlining pieces as proportion of piece radius
+const PIECE_OUTLINE_PROPORTION: f64 = 0.25;
+/// Proportion of square that piece fills as proportion of min cell dimension
+const PIECE_PROPORTION: f64 = 0.6;
 
 /// Used to paint boards onto HTML canvases
 #[wasm_bindgen]
@@ -72,7 +72,7 @@ pub struct Painter {
     king_line: JsValue,
 
     piece_lines: bool,
-    piece_line_width: f64,
+    piece_line_proportion: f64,
 
     square_outline: JsValue,
     outline_width: f64,
@@ -168,7 +168,7 @@ impl Painter {
             selected_piece_line: JsValue::from_str(SELECTED_PIECE_OUTLINE),
             king_line: JsValue::from_str(KING_OUTLINE),
             piece_lines: DRAW_PIECE_OUTLINES,
-            piece_line_width: PIECE_OUTLINE_WIDTH,
+            piece_line_proportion: PIECE_OUTLINE_PROPORTION,
 
             square_outline: JsValue::from_str(SQUARE_OUTLINE),
             outline_width: OUTLINE_WIDTH,
@@ -201,7 +201,7 @@ impl Painter {
             selected_piece_line: JsValue::from_str(SELECTED_PIECE_OUTLINE),
             king_line: JsValue::from_str(KING_OUTLINE),
             piece_lines: DRAW_PIECE_OUTLINES,
-            piece_line_width: PIECE_OUTLINE_WIDTH,
+            piece_line_proportion: PIECE_OUTLINE_PROPORTION,
 
             square_outline: JsValue::from_str(SQUARE_OUTLINE),
             outline_width: OUTLINE_WIDTH,
@@ -255,12 +255,19 @@ impl Painter {
         let cell_height = self.height as usize / board.height;
         let cell_width = self.width as usize / board.width;
         
+        let min_dimension = usize::min(cell_width, cell_height) as f64;
+
+        let cell_radius = min_dimension * PIECE_PROPORTION / 2.0;
+
+        let piece_outline = cell_radius * self.piece_line_proportion;
+        let square_outline = min_dimension * self.outline_width;
+
         self.context.set_fill_style(&self.white_square);
         self.context.fill_rect(0.0, 0.0, self.width as f64, self.height as f64);
 
         self.context.set_fill_style(&self.black_square);
         self.context.set_stroke_style(&self.square_outline);
-        self.context.set_line_width(self.outline_width);
+        self.context.set_line_width(square_outline);
 
         // Draw black squares onto canvas
         for i in 0..board.height {
@@ -336,7 +343,7 @@ impl Painter {
                     match self.context.arc(
                         center_x, 
                         center_y, 
-                        (cell_width as f64 / 2.0) - PIECE_MARGIN, // radius 
+                        cell_radius, // radius 
                         0.0, // start angle
                         f64::consts::PI * 2.0) // end angle
                     {
@@ -346,7 +353,7 @@ impl Painter {
                     self.context.fill();
 
                     if self.piece_lines {
-                        self.context.set_line_width(self.piece_line_width);
+                        self.context.set_line_width(piece_outline);
                         self.context.stroke()
                     }
 
@@ -366,7 +373,7 @@ impl Painter {
             match self.context.arc(
                 center_x, 
                 center_y, 
-                (cell_width as f64 / 2.0) - PIECE_MARGIN, // radius 
+                cell_radius, // radius 
                 0.0, // start angle
                 f64::consts::PI * 2.0) // end angle
             {
@@ -376,7 +383,7 @@ impl Painter {
             self.context.fill();
 
             if self.piece_lines {
-                self.context.set_line_width(self.piece_line_width);
+                self.context.set_line_width(piece_outline);
                 self.context.stroke()
             }
         }

www/index.html

@@ -119,7 +119,7 @@
                 </div>
             </div>
             <div class="row p-3">
-                <div class="col-sm-4" title="should the AI play?">
+                <div class="col-sm-3" title="should the AI play?">
                     <input class="form-check-input" 
                         type="checkbox" 
                         value="" 
@@ -129,15 +129,19 @@
                         AI Player
                     </label>
                 </div>
-                <div class="col-sm-4" title="how many layers deep should the AI search (grows exponentially, be careful)">
+                <div class="col-sm-3" title="how many layers deep should the AI search (grows exponentially, be careful)">
                     <input type="number" 
                         id="ai_search_depth" 
                         name="ai_search_depth" 
                         min="1" max="10" value="4" 
                         class="form-control">
-                    <label for="ai_search_depth">ai difficulty <small class="text-muted">moves ahead</small></label>
+                    <label for="ai_search_depth">ai clairvoyance <small class="text-muted">moves ahead</small></label>
                 </div>
-                <div class="col-sm-4" title="how many nodes were expanded in the search tree">
+                <div class="col-sm-3" title="what percentage of the AI's moves should be perfect?">
+                    <label for="ai_difficulty" class="form-label">ai difficulty <small class="text-muted">%</small></label>
+                    <input type="range" class="form-range" min="1" max="100" id="ai_difficulty">
+                </div>
+                <div class="col-sm-3" title="how many nodes were expanded in the search tree">
                     <p class="text-muted" id="node-count"></p>
                 </div>
             </div>

www/index.js

@@ -13,6 +13,7 @@ var BOARD_HEIGHT = 8;
 
 var PIECE_ROWS = 3;
 var SEARCH_DEPTH = 4;
+var PERFECT_CHANCE = 0.5;
 
 const STATUS_TIMEOUT = 3000;
 const WON_TIMEOUT = 3000;
@@ -137,7 +138,7 @@ function process_canvas_click(cell_coord) {
                 switch(status) {
                     case Moveable.Allowed:
 
-                        if (aiCheckBox.checked) {
+                        if (aiCheckBox.checked && game.has_won() === undefined) {
                             game.ai_move();
                             nodeCountText.innerText = `searched ${game.last_node_count.toLocaleString("en-GB")} possible moves`;
                         }
@@ -338,3 +339,15 @@ const onAICheck = () => {
 }
 aiCheckBox.onchange = onAICheck;
 // aiCheckBox.checked = true;
+
+const aiPerfectChance = document.getElementById("ai_difficulty");
+/**
+ * Handler for piece rows input box change, start a new game
+ */
+const onPerfectChance = () => {
+
+    PERFECT_CHANCE = parseInt(aiPerfectChance.value) / 100;
+    game.set_perfect_chance(PERFECT_CHANCE);
+}
+aiPerfectChance.onchange = onPerfectChance;
+aiPerfectChance.value = 50;