X-Git-Url: https://git.auder.net/?a=blobdiff_plain;f=base_rules.js;h=efeb07887f0a4e1a72a2bc7e927e5fa641fc18c2;hb=c9ab034035a3cac65e4ac9f48a946ecef5ed111e;hp=6f11aa13225133ef932a12b573d5b8f092ee554a;hpb=fd31883bca850ffe4b854d8cc52d7457a61b9010;p=xogo.git

diff --git a/base_rules.js b/base_rules.js
index 6f11aa1..efeb078 100644
--- a/base_rules.js
+++ b/base_rules.js
@@ -4,8 +4,13 @@ import PiPo from "/utils/PiPo.js";
 import Move from "/utils/Move.js";
 
 // NOTE: x coords: top to bottom (white perspective); y: left to right
+// NOTE: ChessRules is aliased as window.C, and variants as window.V
 export default class ChessRules {
 
+  static get Aliases() {
+    return {'C': ChessRules};
+  }
+
   /////////////////////////
   // VARIANT SPECIFICATIONS
 
@@ -14,22 +19,28 @@ export default class ChessRules {
   // Users can generally select a randomness level from 0 to 2.
   static get Options() {
     return {
-      // NOTE: some options are required for FEN generation, some aren't.
       select: [{
         label: "Randomness",
         variable: "randomness",
         defaut: 0,
         options: [
-          { label: "Deterministic", value: 0 },
-          { label: "Symmetric random", value: 1 },
-          { label: "Asymmetric random", value: 2 }
+          {label: "Deterministic", value: 0},
+          {label: "Symmetric random", value: 1},
+          {label: "Asymmetric random", value: 2}
         ]
       }],
-      check: [{
-        label: "Capture king?",
-        defaut: false,
-        variable: "taking"
-      }],
+      check: [
+        {
+          label: "Capture king",
+          defaut: false,
+          variable: "taking"
+        },
+        {
+          label: "Falling pawn",
+          defaut: false,
+          variable: "pawnfall"
+        }
+      ],
       // Game modifiers (using "elementary variants"). Default: false
       styles: [
         "atomic",
@@ -50,18 +61,8 @@ export default class ChessRules {
     };
   }
 
-  // Pawns specifications
-  get pawnSpecs() {
-    return {
-      directions: { 'w': -1, 'b': 1 },
-      initShift: { w: 1, b: 1 },
-      twoSquares: true,
-      threeSquares: false,
-      canCapture: true,
-      captureBackward: false,
-      bidirectional: false,
-      promotions: ['r', 'n', 'b', 'q']
-    };
+  get pawnPromotions() {
+    return ['q', 'r', 'n', 'b'];
   }
 
   // Some variants don't have flags:
@@ -91,9 +92,10 @@ export default class ChessRules {
 
   // Some variants use click infos:
   doClick([x, y]) {
-    if (typeof x != "number") return null; //click on reserves
+    if (typeof x != "number")
+      return null; //click on reserves
     if (
-      this.options["teleport"] && this.subTurn == 2 &&
+      this.options["teleport"] && this.subTurnTeleport == 2 &&
       this.board[x][y] == ""
     ) {
       return new Move({
@@ -139,17 +141,15 @@ export default class ChessRules {
   // a2 --> {x:2,y:0} (this is in fact a6)
   static SquareToCoords(sq) {
     return {
-      x: ChessRules.RowToCoord(sq[1]),
+      x: C.RowToCoord(sq[1]),
       // NOTE: column is always one char => max 26 columns
-      y: ChessRules.ColumnToCoord(sq[0])
+      y: C.ColumnToCoord(sq[0])
     };
   }
 
   // {x:0,y:4} --> e0 (should be e8)
   static CoordsToSquare(coords) {
-    return (
-      ChessRules.CoordToColumn(coords.y) + ChessRules.CoordToRow(coords.x)
-    );
+    return C.CoordToColumn(coords.y) + C.CoordToRow(coords.x);
   }
 
   coordsToId([x, y]) {
@@ -160,7 +160,8 @@ export default class ChessRules {
   }
 
   idToCoords(targetId) {
-    if (!targetId) return null; //outside page, maybe...
+    if (!targetId)
+      return null; //outside page, maybe...
     const idParts = targetId.split('|'); //prefix|sq-2-3 (start at 0 => 3,4)
     if (
       idParts.length < 2 ||
@@ -194,7 +195,7 @@ export default class ChessRules {
     Random.setSeed(seed);
 
     let fen, flags = "0707";
-    if (this.options.randomness == 0 || !this.options.randomness)
+    if (!this.options.randomness)
       // Deterministic:
       fen = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w 0";
 
@@ -261,11 +262,16 @@ export default class ChessRules {
     }
     // Add turn + flags + enpassant (+ reserve)
     let parts = [];
-    if (this.hasFlags) parts.push(`"flags":"${flags}"`);
-    if (this.hasEnpassant) parts.push('"enpassant":"-"');
-    if (this.hasReserve) parts.push('"reserve":"000000000000"');
-    if (this.options["crazyhouse"]) parts.push('"ispawn":"-"');
-    if (parts.length >= 1) fen += " {" + parts.join(",") + "}";
+    if (this.hasFlags)
+      parts.push(`"flags":"${flags}"`);
+    if (this.hasEnpassant)
+      parts.push('"enpassant":"-"');
+    if (this.hasReserve)
+      parts.push('"reserve":"000000000000"');
+    if (this.options["crazyhouse"])
+      parts.push('"ispawn":"-"');
+    if (parts.length >= 1)
+      fen += " {" + parts.join(",") + "}";
     return fen;
   }
 
@@ -277,7 +283,8 @@ export default class ChessRules {
       turn: fenParts[1],
       movesCount: fenParts[2]
     };
-    if (fenParts.length > 3) res = Object.assign(res, JSON.parse(fenParts[3]));
+    if (fenParts.length > 3)
+      res = Object.assign(res, JSON.parse(fenParts[3]));
     return res;
   }
 
@@ -289,13 +296,16 @@ export default class ChessRules {
       this.movesCount
     );
     let parts = [];
-    if (this.hasFlags) parts.push(`"flags":"${this.getFlagsFen()}"`);
+    if (this.hasFlags)
+      parts.push(`"flags":"${this.getFlagsFen()}"`);
     if (this.hasEnpassant)
       parts.push(`"enpassant":"${this.getEnpassantFen()}"`);
-    if (this.hasReserve) parts.push(`"reserve":"${this.getReserveFen()}"`);
+    if (this.hasReserve)
+      parts.push(`"reserve":"${this.getReserveFen()}"`);
     if (this.options["crazyhouse"])
       parts.push(`"ispawn":"${this.getIspawnFen()}"`);
-    if (parts.length >= 1) fen += " {" + parts.join(",") + "}";
+    if (parts.length >= 1)
+      fen += " {" + parts.join(",") + "}";
     return fen;
   }
 
@@ -304,9 +314,11 @@ export default class ChessRules {
     const format = (count) => {
       // if more than 9 consecutive free spaces, break the integer,
       // otherwise FEN parsing will fail.
-      if (count <= 9) return count;
+      if (count <= 9)
+        return count;
       // Most boards of size < 18:
-      if (count <= 18) return "9" + (count - 9);
+      if (count <= 18)
+        return "9" + (count - 9);
       // Except Gomoku:
       return "99" + (count - 18);
     };
@@ -314,7 +326,8 @@ export default class ChessRules {
     for (let i = 0; i < this.size.y; i++) {
       let emptyCount = 0;
       for (let j = 0; j < this.size.x; j++) {
-        if (this.board[i][j] == "") emptyCount++;
+        if (this.board[i][j] == "")
+          emptyCount++;
         else {
           if (emptyCount > 0) {
             // Add empty squares in-between
@@ -327,7 +340,8 @@ export default class ChessRules {
       if (emptyCount > 0)
         // "Flush remainder"
         position += format(emptyCount);
-      if (i < this.size.y - 1) position += "/"; //separate rows
+      if (i < this.size.y - 1)
+        position += "/"; //separate rows
     }
     return position;
   }
@@ -345,8 +359,9 @@ export default class ChessRules {
 
   // Enpassant part of the FEN string
   getEnpassantFen() {
-    if (!this.epSquare) return "-"; //no en-passant
-    return ChessRules.CoordsToSquare(this.epSquare);
+    if (!this.epSquare)
+      return "-"; //no en-passant
+    return C.CoordsToSquare(this.epSquare);
   }
 
   getReserveFen() {
@@ -357,8 +372,9 @@ export default class ChessRules {
 
   getIspawnFen() {
     const coords = Object.keys(this.ispawn);
-    if (coords.length == 0) return "-";
-    return coords.map(ChessRules.CoordsToSquare).join(",");
+    if (coords.length == 0)
+      return "-";
+    return coords.join(",");
   }
 
   // Set flags from fen (castle: white a,h then black a,h)
@@ -372,14 +388,14 @@ export default class ChessRules {
   //////////////////
   // INITIALIZATION
 
-  // Fen string fully describes the game state
   constructor(o) {
     this.options = o.options;
     this.playerColor = o.color;
     this.afterPlay = o.afterPlay;
 
-    // FEN-related:
-    if (!o.fen) o.fen = this.genRandInitFen(o.seed);
+    // Fen string fully describes the game state
+    if (!o.fen)
+      o.fen = this.genRandInitFen(o.seed);
     const fenParsed = this.parseFen(o.fen);
     this.board = this.getBoard(fenParsed.position);
     this.turn = fenParsed.turn;
@@ -401,9 +417,11 @@ export default class ChessRules {
         const character = rows[i][indexInRow];
         const num = parseInt(character, 10);
         // If num is a number, just shift j:
-        if (!isNaN(num)) j += num;
+        if (!isNaN(num))
+          j += num;
         // Else: something at position i,j
-        else board[i][j++] = this.fen2board(character);
+        else
+          board[i][j++] = this.fen2board(character);
       }
     }
     return board;
@@ -412,123 +430,108 @@ export default class ChessRules {
   // Some additional variables from FEN (variant dependant)
   setOtherVariables(fenParsed) {
     // Set flags and enpassant:
-    if (this.hasFlags) this.setFlags(fenParsed.flags);
+    if (this.hasFlags)
+      this.setFlags(fenParsed.flags);
     if (this.hasEnpassant)
       this.epSquare = this.getEpSquare(fenParsed.enpassant);
-    if (this.hasReserve) this.initReserves(fenParsed.reserve);
-    if (this.options["crazyhouse"]) this.initIspawn(fenParsed.ispawn);
+    if (this.hasReserve)
+      this.initReserves(fenParsed.reserve);
+    if (this.options["crazyhouse"])
+      this.initIspawn(fenParsed.ispawn);
     this.subTurn = 1; //may be unused
-    if (this.options["teleport"]) this.captured = null;
+    if (this.options["teleport"]) {
+      this.subTurnTeleport = 1;
+      this.captured = null;
+    }
     if (this.options["dark"]) {
-      this.enlightened = ArrayFun.init(this.size.x, this.size.y);
       // Setup enlightened: squares reachable by player side
-      this.updateEnlightened(false);
+      this.enlightened = ArrayFun.init(this.size.x, this.size.y, false);
+      this.updateEnlightened();
     }
   }
 
-  updateEnlightened(withGraphics) {
-    let newEnlightened = ArrayFun.init(this.size.x, this.size.y, false);
-    const pawnShift = { w: -1, b: 1 };
+  updateEnlightened() {
+    this.oldEnlightened = this.enlightened;
+    this.enlightened = ArrayFun.init(this.size.x, this.size.y, false);
     // Add pieces positions + all squares reachable by moves (includes Zen):
-    // (watch out special pawns case)
     for (let x=0; x<this.size.x; x++) {
       for (let y=0; y<this.size.y; y++) {
         if (this.board[x][y] != "" && this.getColor(x, y) == this.playerColor)
         {
-          newEnlightened[x][y] = true;
-          const piece = this.getPiece(x, y);
-          if (piece == ChessRules.PAWN) {
-            // Attacking squares wouldn't be highlighted if no captures:
-            this.pieces(this.playerColor)[piece].attack.forEach(step => {
-              const [i, j] = [x + step[0], this.computeY(y + step[1])];
-              if (this.onBoard(i, j) && this.board[i][j] == "")
-                newEnlightened[i][j] = true;
-            });
-          }
+          this.enlightened[x][y] = true;
           this.getPotentialMovesFrom([x, y]).forEach(m => {
-            newEnlightened[m.end.x][m.end.y] = true;
+            this.enlightened[m.end.x][m.end.y] = true;
           });
         }
       }
     }
-    if (this.epSquare) this.enlightEnpassant(newEnlightened);
-    if (withGraphics) this.graphUpdateEnlightened(newEnlightened);
-    this.enlightened = newEnlightened;
+    if (this.epSquare)
+      this.enlightEnpassant();
   }
 
-  // Include en-passant capturing square if any:
-  enlightEnpassant(newEnlightened) {
-    const steps = this.pieces(this.playerColor)[ChessRules.PAWN].attack;
+  // Include square of the en-passant capturing square:
+  enlightEnpassant() {
+    // NOTE: shortcut, pawn has only one attack type, doesn't depend on square
+    const steps = this.pieces(this.playerColor)["p"].attack[0].steps;
     for (let step of steps) {
       const x = this.epSquare.x - step[0],
             y = this.computeY(this.epSquare.y - step[1]);
       if (
         this.onBoard(x, y) &&
         this.getColor(x, y) == this.playerColor &&
-        this.getPiece(x, y) == ChessRules.PAWN
+        this.getPieceType(x, y) == "p"
       ) {
-        newEnlightened[x][this.epSquare.y] = true;
+        this.enlightened[x][this.epSquare.y] = true;
         break;
       }
     }
   }
 
-  // Apply diff this.enlightened --> newEnlightened on board
-  graphUpdateEnlightened(newEnlightened) {
-    let container = document.getElementById(this.containerId);
-    const r = container.getBoundingClientRect();
+  // Apply diff this.enlightened --> oldEnlightened on board
+  graphUpdateEnlightened() {
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
+    const r = chessboard.getBoundingClientRect();
     const pieceWidth = this.getPieceWidth(r.width);
     for (let x=0; x<this.size.x; x++) {
       for (let y=0; y<this.size.y; y++) {
-        if (this.enlightened[x][y] && !newEnlightened[x][y]) {
+        if (!this.enlightened[x][y] && this.oldEnlightened[x][y]) {
           let elt = document.getElementById(this.coordsToId([x, y]));
-          elt.style.fillOpacity = "0.5";
-          if (this.g_pieces[x][y]) {
-            this.g_pieces[x][y].remove();
-            this.g_pieces[x][y] = null;
-          }
+          elt.classList.add("in-shadow");
+          if (this.g_pieces[x][y])
+            this.g_pieces[x][y].classList.add("hidden");
         }
-        else if (!this.enlightened[x][y] && newEnlightened[x][y]) {
+        else if (this.enlightened[x][y] && !this.oldEnlightened[x][y]) {
           let elt = document.getElementById(this.coordsToId([x, y]));
-          elt.style.fillOpacity = "1";
-          if (this.board[x][y] != "") {
-            const piece = this.getPiece(x, y);
-            const color = this.getColor(x, y);
-            this.g_pieces[x][y] = document.createElement("piece");
-            let newClasses = [
-              this.pieces()[piece]["class"],
-              color == "w" ? "white" : "black"
-            ];
-            newClasses.forEach(cl => this.g_pieces[x][y].classList.add(cl));
-            this.g_pieces[x][y].style.width = pieceWidth + "px";
-            this.g_pieces[x][y].style.height = pieceWidth + "px";
-            const [ip, jp] = this.getPixelPosition(x, y, r);
-            this.g_pieces[x][y].style.transform =
-              `translate(${ip}px,${jp}px)`;
-            container.appendChild(this.g_pieces[x][y]);
-          }
+          elt.classList.remove("in-shadow");
+          if (this.g_pieces[x][y])
+            this.g_pieces[x][y].classList.remove("hidden");
         }
       }
     }
   }
 
-  // ordering p,r,n,b,q,k (most general + count in base 30 if needed)
+  // ordering as in pieces() p,r,n,b,q,k (+ count in base 30 if needed)
   initReserves(reserveStr) {
     const counts = reserveStr.split("").map(c => parseInt(c, 30));
     this.reserve = { w: {}, b: {} };
-    const pieceName = Object.keys(this.pieces());
-    for (let i of ArrayFun.range(12)) {
-      if (i < 6) this.reserve['w'][pieceName[i]] = counts[i];
-      else this.reserve['b'][pieceName[i-6]] = counts[i];
+    const pieceName = ['p', 'r', 'n', 'b', 'q', 'k'];
+    const L = pieceName.length;
+    for (let i of ArrayFun.range(2 * L)) {
+      if (i < L)
+        this.reserve['w'][pieceName[i]] = counts[i];
+      else
+        this.reserve['b'][pieceName[i-L]] = counts[i];
     }
   }
 
   initIspawn(ispawnStr) {
     if (ispawnStr != "-") {
-      this.ispawn = ispawnStr.split(",").map(ChessRules.SquareToCoords)
+      this.ispawn = ispawnStr.split(",").map(C.SquareToCoords)
                     .reduce((o, key) => ({ ...o, [key]: true}), {});
     }
-    else this.ispawn = {};
+    else
+      this.ispawn = {};
   }
 
   getNbReservePieces(color) {
@@ -563,17 +566,18 @@ export default class ChessRules {
     window.onresize = () => this.re_drawBoardElements();
     this.re_drawBoardElements();
     this.initMouseEvents();
-    const container = document.getElementById(this.containerId);
-    new ResizeObserver(this.rescale).observe(container);
+    const chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
+    new ResizeObserver(this.rescale).observe(chessboard);
   }
 
   re_drawBoardElements() {
     const board = this.getSvgChessboard();
-    const oppCol = ChessRules.GetOppCol(this.playerColor);
-    let container = document.getElementById(this.containerId);
-    container.innerHTML = "";
-    container.insertAdjacentHTML('beforeend', board);
-    let cb = container.querySelector("#" + this.containerId + "_SVG");
+    const oppCol = C.GetOppCol(this.playerColor);
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
+    chessboard.innerHTML = "";
+    chessboard.insertAdjacentHTML('beforeend', board);
     const aspectRatio = this.size.y / this.size.x;
     // Compare window ratio width / height to aspectRatio:
     const windowRatio = window.innerWidth / window.innerHeight;
@@ -596,13 +600,13 @@ export default class ChessRules {
         cbWidth = cbHeight * aspectRatio;
       }
     }
-    container.style.width = cbWidth + "px";
-    container.style.height = cbHeight + "px";
+    chessboard.style.width = cbWidth + "px";
+    chessboard.style.height = cbHeight + "px";
     // Center chessboard:
     const spaceLeft = (window.innerWidth - cbWidth) / 2,
           spaceTop = (window.innerHeight - cbHeight) / 2;
-    container.style.left = spaceLeft + "px";
-    container.style.top = spaceTop + "px";
+    chessboard.style.left = spaceLeft + "px";
+    chessboard.style.top = spaceTop + "px";
     // Give sizes instead of recomputing them,
     // because chessboard might not be drawn yet.
     this.setupPieces({
@@ -621,19 +625,18 @@ export default class ChessRules {
       <svg
         viewBox="0 0 80 80"
         version="1.1"
-        id="${this.containerId}_SVG">
+        class="chessboard_SVG">
       <g>`;
     for (let i=0; i < sizeX; i++) {
       for (let j=0; j < sizeY; j++) {
         const ii = (flipped ? this.size.x - 1 - i : i);
         const jj = (flipped ? this.size.y - 1 - j : j);
-        let fillOpacity = '1';
-        if (this.options["dark"] && !this.enlightened[ii][jj])
-          fillOpacity = '0.5';
+        let classes = this.getSquareColorClass(ii, jj);
+        if (this.enlightened && !this.enlightened[ii][jj])
+          classes += " in-shadow";
         // NOTE: x / y reversed because coordinates system is reversed.
-        // TODO: CSS "wood" style, rect --> style --> background-image ?
-        board += `<rect style="fill-opacity:${fillOpacity};
-                               fill:#${this.getSquareColor(ii, jj)}"
+        board += `<rect
+          class="${classes}"
           id="${this.coordsToId([ii, jj])}"
           width="10"
           height="10"
@@ -645,9 +648,9 @@ export default class ChessRules {
     return board;
   }
 
-  // Generally light square bottom-right; TODO: user-defined colors at least
-  getSquareColor(i, j) {
-    return ((i+j) % 2 == 0 ? "f0d9b5": "b58863");
+  // Generally light square bottom-right
+  getSquareColorClass(i, j) {
+    return ((i+j) % 2 == 0 ? "light-square": "dark-square");
   }
 
   setupPieces(r) {
@@ -662,17 +665,18 @@ export default class ChessRules {
         }
       }
     }
-    else this.g_pieces = ArrayFun.init(this.size.x, this.size.y, null);
-    let container = document.getElementById(this.containerId);
+    else
+      this.g_pieces = ArrayFun.init(this.size.x, this.size.y, null);
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
+    if (!r)
+      r = chessboard.getBoundingClientRect();
     const pieceWidth = this.getPieceWidth(r.width);
     for (let i=0; i < this.size.x; i++) {
       for (let j=0; j < this.size.y; j++) {
-        if (
-          this.board[i][j] != "" &&
-          (!this.options["dark"] || this.enlightened[i][j])
-        ) {
-          const piece = this.getPiece(i, j);
+        if (this.board[i][j] != "") {
           const color = this.getColor(i, j);
+          const piece = this.getPiece(i, j);
           this.g_pieces[i][j] = document.createElement("piece");
           this.g_pieces[i][j].classList.add(this.pieces()[piece]["class"]);
           this.g_pieces[i][j].classList.add(color == "w" ? "white" : "black");
@@ -680,11 +684,14 @@ export default class ChessRules {
           this.g_pieces[i][j].style.height = pieceWidth + "px";
           const [ip, jp] = this.getPixelPosition(i, j, r);
           this.g_pieces[i][j].style.transform = `translate(${ip}px,${jp}px)`;
-          container.appendChild(this.g_pieces[i][j]);
+          if (this.enlightened && !this.enlightened[i][j])
+            this.g_pieces[i][j].classList.add("hidden");
+          chessboard.appendChild(this.g_pieces[i][j]);
         }
       }
     }
-    if (this.reserve) this.re_drawReserve(['w', 'b'], r);
+    if (this.reserve)
+      this.re_drawReserve(['w', 'b'], r);
   }
 
   // NOTE: assume !!this.reserve
@@ -692,7 +699,8 @@ export default class ChessRules {
     if (this.r_pieces) {
       // Remove (old) reserve pieces
       for (let c of colors) {
-        if (!this.reserve[c]) continue;
+        if (!this.reserve[c])
+          continue;
         Object.keys(this.reserve[c]).forEach(p => {
           if (this.r_pieces[c][p]) {
             this.r_pieces[c][p].remove();
@@ -702,19 +710,21 @@ export default class ChessRules {
           }
         });
         let reservesDiv = document.getElementById("reserves_" + c);
-        if (reservesDiv) reservesDiv.remove();
+        if (reservesDiv)
+          reservesDiv.remove();
       }
     }
-    else this.r_pieces = { 'w': {}, 'b': {} };
-    if (!r) {
-      const container = document.getElementById(this.containerId);
-      r = container.getBoundingClientRect();
-    }
-    const epsilon = 1e-4; //fix display bug on Firefox at least
+    else
+      this.r_pieces = { 'w': {}, 'b': {} };
+    let container = document.getElementById(this.containerId);
+    if (!r)
+      r = container.querySelector(".chessboard").getBoundingClientRect();
     for (let c of colors) {
-      if (!this.reserve[c]) continue;
+      if (!this.reserve[c])
+        continue;
       const nbR = this.getNbReservePieces(c);
-      if (nbR == 0) continue;
+      if (nbR == 0)
+        continue;
       const sqResSize = this.getReserveSquareSize(r.width, nbR);
       let ridx = 0;
       const vShift = (c == this.playerColor ? r.height + 5 : -sqResSize - 5);
@@ -724,19 +734,21 @@ export default class ChessRules {
       rcontainer.classList.add("reserves");
       rcontainer.style.left = i0 + "px";
       rcontainer.style.top = j0 + "px";
-      rcontainer.style.width = (nbR * sqResSize) + "px";
+      // NOTE: +1 fix display bug on Firefox at least
+      rcontainer.style.width = (nbR * sqResSize + 1) + "px";
       rcontainer.style.height = sqResSize + "px";
-      document.getElementById("boardContainer").appendChild(rcontainer);
+      container.appendChild(rcontainer);
       for (let p of Object.keys(this.reserve[c])) {
-        if (this.reserve[c][p] == 0) continue;
+        if (this.reserve[c][p] == 0)
+          continue;
         let r_cell = document.createElement("div");
         r_cell.id = this.coordsToId([c, p]);
         r_cell.classList.add("reserve-cell");
-        r_cell.style.width = (sqResSize - epsilon) + "px";
-        r_cell.style.height = (sqResSize - epsilon) + "px";
+        r_cell.style.width = sqResSize + "px";
+        r_cell.style.height = sqResSize + "px";
         rcontainer.appendChild(r_cell);
         let piece = document.createElement("piece");
-        const pieceSpec = this.pieces(c)[p];
+        const pieceSpec = this.pieces()[p];
         piece.classList.add(pieceSpec["class"]);
         piece.classList.add(c == 'w' ? "white" : "black");
         piece.style.width = "100%";
@@ -757,10 +769,13 @@ export default class ChessRules {
   }
 
   updateReserve(color, piece, count) {
+    if (this.options["cannibal"] && C.CannibalKings[piece])
+      piece = "k"; //capturing cannibal king: back to king form
     const oldCount = this.reserve[color][piece];
     this.reserve[color][piece] = count;
     // Redrawing is much easier if count==0
-    if ([oldCount, count].includes(0)) this.re_drawReserve([color]);
+    if ([oldCount, count].includes(0))
+      this.re_drawReserve([color]);
     else {
       const numId = this.getReserveNumId(color, piece);
       document.getElementById(numId).textContent = count;
@@ -769,30 +784,32 @@ export default class ChessRules {
 
   // After resize event: no need to destroy/recreate pieces
   rescale() {
-    let container = document.getElementById(this.containerId);
-    if (!container) return; //useful at initial loading
-    const r = container.getBoundingClientRect();
+    const container = document.getElementById(this.containerId);
+    if (!container)
+      return; //useful at initial loading
+    let chessboard = container.querySelector(".chessboard");
+    const r = chessboard.getBoundingClientRect();
     const newRatio = r.width / r.height;
     const aspectRatio = this.size.y / this.size.x;
     let newWidth = r.width,
         newHeight = r.height;
     if (newRatio > aspectRatio) {
       newWidth = r.height * aspectRatio;
-      container.style.width = newWidth + "px";
+      chessboard.style.width = newWidth + "px";
     }
     else if (newRatio < aspectRatio) {
       newHeight = r.width / aspectRatio;
-      container.style.height = newHeight + "px";
+      chessboard.style.height = newHeight + "px";
     }
     const newX = (window.innerWidth - newWidth) / 2;
-    container.style.left = newX + "px";
+    chessboard.style.left = newX + "px";
     const newY = (window.innerHeight - newHeight) / 2;
-    container.style.top = newY + "px";
+    chessboard.style.top = newY + "px";
     const newR = { x: newX, y: newY, width: newWidth, height: newHeight };
     const pieceWidth = this.getPieceWidth(newWidth);
     for (let i=0; i < this.size.x; i++) {
       for (let j=0; j < this.size.y; j++) {
-        if (this.board[i][j] != "") {
+        if (this.g_pieces[i][j]) {
           // NOTE: could also use CSS transform "scale"
           this.g_pieces[i][j].style.width = pieceWidth + "px";
           this.g_pieces[i][j].style.height = pieceWidth + "px";
@@ -801,15 +818,17 @@ export default class ChessRules {
         }
       }
     }
-    if (this.reserve) this.rescaleReserve(newR);
+    if (this.reserve)
+      this.rescaleReserve(newR);
   }
 
   rescaleReserve(r) {
-    const epsilon = 1e-4;
     for (let c of ['w','b']) {
-      if (!this.reserve[c]) continue;
+      if (!this.reserve[c])
+        continue;
       const nbR = this.getNbReservePieces(c);
-      if (nbR == 0) continue;
+      if (nbR == 0)
+        continue;
       // Resize container first
       const sqResSize = this.getReserveSquareSize(r.width, nbR);
       const vShift = (c == this.playerColor ? r.height + 5 : -sqResSize - 5);
@@ -817,25 +836,27 @@ export default class ChessRules {
       let rcontainer = document.getElementById("reserves_" + c);
       rcontainer.style.left = i0 + "px";
       rcontainer.style.top = j0 + "px";
-      rcontainer.style.width = (nbR * sqResSize) + "px";
+      rcontainer.style.width = (nbR * sqResSize + 1) + "px";
       rcontainer.style.height = sqResSize + "px";
       // And then reserve cells:
       const rpieceWidth = this.getReserveSquareSize(r.width, nbR);
       Object.keys(this.reserve[c]).forEach(p => {
-        if (this.reserve[c][p] == 0) return;
+        if (this.reserve[c][p] == 0)
+          return;
         let r_cell = document.getElementById(this.coordsToId([c, p]));
-        r_cell.style.width = (sqResSize - epsilon) + "px";
-        r_cell.style.height = (sqResSize - epsilon) + "px";
+        r_cell.style.width = sqResSize + "px";
+        r_cell.style.height = sqResSize + "px";
       });
     }
   }
 
-  // Return the absolute pixel coordinates given current position.
+  // Return the absolute pixel coordinates (on board) given current position.
   // Our coordinate system differs from CSS one (x <--> y).
   // We return here the CSS coordinates (more useful).
   getPixelPosition(i, j, r) {
     const sqSize = this.getSquareWidth(r.width);
-    if (i < 0 || j < 0) return [0, 0]; //piece vanishes
+    if (i < 0 || j < 0)
+      return [0, 0]; //piece vanishes
     const flipped = (this.playerColor == 'b');
     const x = (flipped ? this.size.y - 1 - j : j) * sqSize;
     const y = (flipped ? this.size.x - 1 - i : i) * sqSize;
@@ -843,10 +864,13 @@ export default class ChessRules {
   }
 
   initMouseEvents() {
-    let container = document.getElementById(this.containerId);
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
 
     const getOffset = e => {
-      if (e.clientX) return {x: e.clientX, y: e.clientY}; //Mouse
+      if (e.clientX)
+        // Mouse
+        return {x: e.clientX, y: e.clientY};
       let touchLocation = null;
       if (e.targetTouches && e.targetTouches.length >= 1)
         // Touch screen, dragstart
@@ -855,15 +879,15 @@ export default class ChessRules {
         // Touch screen, dragend
         touchLocation = e.changedTouches[0];
       if (touchLocation)
-        return {x: touchLocation.pageX, y: touchLocation.pageY};
-      return [0, 0]; //Big trouble here =)
+        return {x: touchLocation.clientX, y: touchLocation.clientY};
+      return [0, 0]; //shouldn't reach here =)
     }
 
     const centerOnCursor = (piece, e) => {
       const centerShift = sqSize / 2;
       const offset = getOffset(e);
-      piece.style.left = (offset.x - centerShift) + "px";
-      piece.style.top = (offset.y - centerShift) + "px";
+      piece.style.left = (offset.x - r.x - centerShift) + "px";
+      piece.style.top = (offset.y - r.y - centerShift) + "px";
     }
 
     let start = null,
@@ -871,16 +895,22 @@ export default class ChessRules {
         startPiece, curPiece = null,
         sqSize;
     const mousedown = (e) => {
-      r = container.getBoundingClientRect();
+      // Disable zoom on smartphones:
+      if (e.touches && e.touches.length > 1)
+        e.preventDefault();
+      r = chessboard.getBoundingClientRect();
       sqSize = this.getSquareWidth(r.width);
       const square = this.idToCoords(e.target.id);
       if (square) {
         const [i, j] = square;
         const move = this.doClick([i, j]);
-        if (move) this.playPlusVisual(move);
+        if (move)
+          this.playPlusVisual(move);
         else {
-          if (typeof i != "number") startPiece = this.r_pieces[i][j];
-          else if (this.g_pieces[i][j]) startPiece = this.g_pieces[i][j];
+          if (typeof i != "number")
+            startPiece = this.r_pieces[i][j];
+          else if (this.g_pieces[i][j])
+            startPiece = this.g_pieces[i][j];
           if (startPiece && this.canIplay(i, j)) {
             e.preventDefault();
             start = { x: i, y: j };
@@ -890,9 +920,9 @@ export default class ChessRules {
             curPiece.style.width = sqSize + "px";
             curPiece.style.height = sqSize + "px";
             centerOnCursor(curPiece, e);
-            document.getElementById("boardContainer").appendChild(curPiece);
+            chessboard.appendChild(curPiece);
             startPiece.style.opacity = "0.4";
-            container.style.cursor = "none";
+            chessboard.style.cursor = "none";
           }
         }
       }
@@ -903,31 +933,37 @@ export default class ChessRules {
         e.preventDefault();
         centerOnCursor(curPiece, e);
       }
+      else if (e.changedTouches && e.changedTouches.length >= 1)
+        // Attempt to prevent horizontal swipe...
+        e.preventDefault();
     };
 
     const mouseup = (e) => {
-      const newR = container.getBoundingClientRect();
+      const newR = chessboard.getBoundingClientRect();
       if (newR.width != r.width || newR.height != r.height) {
         this.rescale();
         return;
       }
-      if (!start) return;
+      if (!start)
+        return;
       const [x, y] = [start.x, start.y];
       start = null;
       e.preventDefault();
-      container.style.cursor = "pointer";
+      chessboard.style.cursor = "pointer";
       startPiece.style.opacity = "1";
       const offset = getOffset(e);
       const landingElt = document.elementFromPoint(offset.x, offset.y);
-      const sq = this.idToCoords(landingElt.id);
+      const sq = landingElt ? this.idToCoords(landingElt.id) : undefined;
       if (sq) {
         const [i, j] = sq;
         // NOTE: clearly suboptimal, but much easier, and not a big deal.
         const potentialMoves = this.getPotentialMovesFrom([x, y])
           .filter(m => m.end.x == i && m.end.y == j);
         const moves = this.filterValid(potentialMoves);
-        if (moves.length >= 2) this.showChoices(moves, r);
-        else if (moves.length == 1) this.playPlusVisual(moves[0], r);
+        if (moves.length >= 2)
+          this.showChoices(moves, r);
+        else if (moves.length == 1)
+          this.playPlusVisual(moves[0], r);
       }
       curPiece.remove();
     };
@@ -938,30 +974,32 @@ export default class ChessRules {
       document.addEventListener("mouseup", mouseup);
     }
     if ('ontouchstart' in window) {
-      document.addEventListener("touchstart", mousedown);
-      document.addEventListener("touchmove", mousemove);
-      document.addEventListener("touchend", mouseup);
+      // https://stackoverflow.com/a/42509310/12660887
+      document.addEventListener("touchstart", mousedown, {passive: false});
+      document.addEventListener("touchmove", mousemove, {passive: false});
+      document.addEventListener("touchend", mouseup, {passive: false});
     }
+    // TODO: onpointerdown/move/up ? See reveal.js /controllers/touch.js
   }
 
   showChoices(moves, r) {
     let container = document.getElementById(this.containerId);
+    let chessboard = container.querySelector(".chessboard");
     let choices = document.createElement("div");
     choices.id = "choices";
     choices.style.width = r.width + "px";
     choices.style.height = r.height + "px";
     choices.style.left = r.x + "px";
     choices.style.top = r.y + "px";
-    container.style.opacity = "0.5";
-    let boardContainer = document.getElementById("boardContainer");
-    boardContainer.appendChild(choices);
+    chessboard.style.opacity = "0.5";
+    container.appendChild(choices);
     const squareWidth = this.getSquareWidth(r.width);
     const firstUpLeft = (r.width - (moves.length * squareWidth)) / 2;
     const firstUpTop = (r.height - squareWidth) / 2;
     const color = moves[0].appear[0].c;
     const callback = (m) => {
-      container.style.opacity = "1";
-      boardContainer.removeChild(choices);
+      chessboard.style.opacity = "1";
+      container.removeChild(choices);
       this.playPlusVisual(m, r);
     }
     for (let i=0; i < moves.length; i++) {
@@ -974,7 +1012,7 @@ export default class ChessRules {
       choice.style.backgroundColor = "lightyellow";
       choice.onclick = () => callback(moves[i]);
       const piece = document.createElement("piece");
-      const pieceSpec = this.pieces(color)[moves[i].appear[0].p];
+      const pieceSpec = this.pieces()[moves[i].appear[0].p];
       piece.classList.add(pieceSpec["class"]);
       piece.classList.add(color == 'w' ? "white" : "black");
       piece.style.width = "100%";
@@ -988,7 +1026,7 @@ export default class ChessRules {
   // BASIC UTILS
 
   get size() {
-    return { "x": 8, "y": 8 };
+    return {"x": 8, "y": 8};
   }
 
   // Color of thing on square (i,j). 'undefined' if square is empty
@@ -996,33 +1034,34 @@ export default class ChessRules {
     return this.board[i][j].charAt(0);
   }
 
-  // Piece type on square (i,j). 'undefined' if square is empty
+  // Assume square i,j isn't empty
   getPiece(i, j) {
     return this.board[i][j].charAt(1);
   }
 
+  // Piece type on square (i,j)
+  getPieceType(i, j) {
+    const p = this.board[i][j].charAt(1);
+    return C.CannibalKings[p] || p; //a cannibal king move as...
+  }
+
   // Get opponent color
   static GetOppCol(color) {
     return (color == "w" ? "b" : "w");
   }
 
-  // Can thing on square1 take thing on square2
+  // Can thing on square1 capture (no return) thing on square2?
   canTake([x1, y1], [x2, y2]) {
-    return (
-      (
-        (this.options["recycle"] || this.options["teleport"]) &&
-        this.getPiece(x2, y2) != ChessRules.KING
-      ) ||
-      (this.getColor(x1, y1) !== this.getColor(x2, y2))
-    );
+    return (this.getColor(x1, y1) !== this.getColor(x2, y2));
   }
 
   // Is (x,y) on the chessboard?
   onBoard(x, y) {
-    return x >= 0 && x < this.size.x && y >= 0 && y < this.size.y;
+    return (x >= 0 && x < this.size.x &&
+            y >= 0 && y < this.size.y);
   }
 
-  // Used in interface: 'side' arg == player color
+  // Used in interface
   canIplay(x, y) {
     return (
       this.playerColor == this.turn &&
@@ -1036,101 +1075,128 @@ export default class ChessRules {
   ////////////////////////
   // PIECES SPECIFICATIONS
 
-  pieces(color) {
+  pieces(color, x, y) {
     const pawnShift = (color == "w" ? -1 : 1);
+    const initRank = ((color == 'w' && x == 6) || (color == 'b' && x == 1));
     return {
       'p': {
         "class": "pawn",
-        steps: [[pawnShift, 0]],
-        range: 1,
-        attack: [[pawnShift, 1], [pawnShift, -1]]
+        moves: [
+          {
+            steps: [[pawnShift, 0]],
+            range: (initRank ? 2 : 1)
+          }
+        ],
+        attack: [
+          {
+            steps: [[pawnShift, 1], [pawnShift, -1]],
+            range: 1
+          }
+        ]
       },
       // rook
       'r': {
         "class": "rook",
-        steps: [[0, 1], [0, -1], [1, 0], [-1, 0]]
+        moves: [
+          {steps: [[0, 1], [0, -1], [1, 0], [-1, 0]]}
+        ]
       },
       // knight
       'n': {
         "class": "knight",
-        steps: [
-          [1, 2], [1, -2], [-1, 2], [-1, -2],
-          [2, 1], [-2, 1], [2, -1], [-2, -1]
-        ],
-        range: 1
+        moves: [
+          {
+            steps: [
+              [1, 2], [1, -2], [-1, 2], [-1, -2],
+              [2, 1], [-2, 1], [2, -1], [-2, -1]
+            ],
+            range: 1
+          }
+        ]
       },
       // bishop
       'b': {
         "class": "bishop",
-        steps: [[1, 1], [1, -1], [-1, 1], [-1, -1]]
+        moves: [
+          {steps: [[1, 1], [1, -1], [-1, 1], [-1, -1]]}
+        ]
       },
       // queen
       'q': {
         "class": "queen",
-        steps: [
-          [0, 1], [0, -1], [1, 0], [-1, 0],
-          [1, 1], [1, -1], [-1, 1], [-1, -1]
+        moves: [
+          {
+            steps: [
+              [0, 1], [0, -1], [1, 0], [-1, 0],
+              [1, 1], [1, -1], [-1, 1], [-1, -1]
+            ]
+          }
         ]
       },
       // king
       'k': {
         "class": "king",
-        steps: [
-          [0, 1], [0, -1], [1, 0], [-1, 0],
-          [1, 1], [1, -1], [-1, 1], [-1, -1]
-        ],
-        range: 1
-      }
+        moves: [
+          {
+            steps: [
+              [0, 1], [0, -1], [1, 0], [-1, 0],
+              [1, 1], [1, -1], [-1, 1], [-1, -1]
+            ],
+            range: 1
+          }
+        ]
+      },
+      // Cannibal kings:
+      '!': {"class": "king-pawn", moveas: "p"},
+      '#': {"class": "king-rook", moveas: "r"},
+      '$': {"class": "king-knight", moveas: "n"},
+      '%': {"class": "king-bishop", moveas: "b"},
+      '*': {"class": "king-queen", moveas: "q"}
     };
   }
 
-  // Some pieces codes (for a clearer code)
-  static get PAWN() {
-    return "p";
-  }
-  static get QUEEN() {
-    return "q";
-  }
-  static get KING() {
-    return "k";
-  }
-
   ////////////////////
   // MOVES GENERATION
 
   // For Cylinder: get Y coordinate
   computeY(y) {
-    if (!this.options["cylinder"]) return y;
+    if (!this.options["cylinder"])
+      return y;
     let res = y % this.size.y;
-    if (res < 0) res += this.size.y;
+    if (res < 0)
+      res += this.size.y;
     return res;
   }
 
   // Stop at the first capture found
   atLeastOneCapture(color) {
     color = color || this.turn;
-    const oppCol = ChessRules.GetOppCol(color);
+    const oppCol = C.GetOppCol(color);
     for (let i = 0; i < this.size.x; i++) {
       for (let j = 0; j < this.size.y; j++) {
         if (this.board[i][j] != "" && this.getColor(i, j) == color) {
-          const specs = this.pieces(color)[this.getPiece(i, j)];
-          const steps = specs.attack || specs.steps;
-          outerLoop: for (let step of steps) {
-            let [ii, jj] = [i + step[0], this.computeY(j + step[1])];
-            let stepCounter = 1;
-            while (this.onBoard(ii, jj) && this.board[ii][jj] == "") {
-              if (specs.range <= stepCounter++) continue outerLoop;
-              ii += step[0];
-              jj = this.computeY(jj + step[1]);
-            }
-            if (
-              this.onBoard(ii, jj) &&
-              this.getColor(ii, jj) == oppCol &&
-              this.filterValid(
-                [this.getBasicMove([i, j], [ii, jj])]
-              ).length >= 1
-            ) {
-              return true;
+          const allSpecs = this.pieces(color, i, j)
+          let specs = allSpecs[this.getPieceType(i, j)];
+          const attacks = specs.attack || specs.moves;
+          for (let a of attacks) {
+            outerLoop: for (let step of a.steps) {
+              let [ii, jj] = [i + step[0], this.computeY(j + step[1])];
+              let stepCounter = 1;
+              while (this.onBoard(ii, jj) && this.board[ii][jj] == "") {
+                if (a.range <= stepCounter++)
+                  continue outerLoop;
+                ii += step[0];
+                jj = this.computeY(jj + step[1]);
+              }
+              if (
+                this.onBoard(ii, jj) &&
+                this.getColor(ii, jj) == oppCol &&
+                this.filterValid(
+                  [this.getBasicMove([i, j], [ii, jj])]
+                ).length >= 1
+              ) {
+                return true;
+              }
             }
           }
         }
@@ -1142,16 +1208,16 @@ export default class ChessRules {
   getDropMovesFrom([c, p]) {
     // NOTE: by design, this.reserve[c][p] >= 1 on user click
     // (but not necessarily otherwise)
-    if (!this.reserve[c][p] || this.reserve[c][p] == 0) return [];
+    if (this.reserve[c][p] == 0)
+      return [];
     let moves = [];
     for (let i=0; i<this.size.x; i++) {
       for (let j=0; j<this.size.y; j++) {
-        // TODO: rather simplify this "if" and add post-condition: more general
         if (
           this.board[i][j] == "" &&
-          (!this.options["dark"] || this.enlightened[i][j]) &&
+          (!this.enlightened || this.enlightened[i][j]) &&
           (
-            p != ChessRules.PAWN ||
+            p != "p" ||
             (c == 'w' && i < this.size.x - 1) ||
             (c == 'b' && i > 0)
           )
@@ -1171,15 +1237,22 @@ export default class ChessRules {
   }
 
   // All possible moves from selected square
-  getPotentialMovesFrom(sq) {
-    if (typeof sq[0] == "string") return this.getDropMovesFrom(sq);
-    if (this.options["madrasi"] && this.isImmobilized(sq)) return [];
-    const piece = this.getPiece(sq[0], sq[1]);
-    let moves;
-    if (piece == ChessRules.PAWN) moves = this.getPotentialPawnMoves(sq);
-    else moves = this.getPotentialMovesOf(piece, sq);
+  getPotentialMovesFrom(sq, color) {
+    if (typeof sq[0] == "string")
+      return this.getDropMovesFrom(sq);
+    if (this.options["madrasi"] && this.isImmobilized(sq))
+      return [];
+    const piece = this.getPieceType(sq[0], sq[1]);
+    let moves = this.getPotentialMovesOf(piece, sq);
     if (
-      piece == ChessRules.KING &&
+      piece == "p" &&
+      this.hasEnpassant &&
+      this.epSquare
+    ) {
+      Array.prototype.push.apply(moves, this.getEnpassantCaptures(sq));
+    }
+    if (
+      piece == "k" &&
       this.hasCastle &&
       this.castleFlags[color || this.turn].some(v => v < this.size.y)
     ) {
@@ -1189,9 +1262,10 @@ export default class ChessRules {
   }
 
   postProcessPotentialMoves(moves) {
-    if (moves.length == 0) return [];
+    if (moves.length == 0)
+      return [];
     const color = this.getColor(moves[0].start.x, moves[0].start.y);
-    const oppCol = ChessRules.GetOppCol(color);
+    const oppCol = C.GetOppCol(color);
 
     if (this.options["capture"] && this.atLeastOneCapture()) {
       // Filter out non-capturing moves (not using m.vanish because of
@@ -1227,7 +1301,7 @@ export default class ChessRules {
             if (
               this.onBoard(x, y) &&
               this.board[x][y] != "" &&
-              this.getPiece(x, y) != ChessRules.PAWN
+              this.getPieceType(x, y) != "p"
             ) {
               m.vanish.push(
                 new PiPo({
@@ -1239,35 +1313,148 @@ export default class ChessRules {
               );
             }
           }
-          if (!this.options["rifle"]) m.appear.pop(); //nothin appears
+          if (!this.options["rifle"])
+            m.appear.pop(); //nothin appears
+        }
+      });
+    }
+
+    if (
+      moves.length > 0 &&
+      this.getPieceType(moves[0].start.x, moves[0].start.y) == "p"
+    ) {
+      let moreMoves = [];
+      const lastRank = (color == "w" ? 0 : this.size.x - 1);
+      const initPiece = this.getPiece(moves[0].start.x, moves[0].start.y);
+      moves.forEach(m => {
+        let finalPieces = ["p"];
+        const [x1, y1] = [m.start.x, m.start.y];
+        const [x2, y2] = [m.end.x, m.end.y];
+        const promotionOk = (
+          x2 == lastRank &&
+          (!this.options["rifle"] || this.board[x2][y2] == "")
+        );
+        if (!promotionOk)
+          return; //nothing to do
+        if (!this.options["pawnfall"]) {
+          if (
+            this.options["cannibal"] &&
+            this.board[x2][y2] != "" &&
+            this.getColor(x2, y2) == oppCol
+          ) {
+            finalPieces = [this.getPieceType(x2, y2)];
+          }
+          else
+            finalPieces = this.pawnPromotions;
+        }
+        m.appear[0].p = finalPieces[0];
+        if (initPiece == "!") //cannibal king-pawn
+          m.appear[0].p = C.CannibalKingCode[finalPieces[0]];
+        for (let i=1; i<finalPieces.length; i++) {
+          const piece = finalPieces[i];
+          let tr = null;
+          if (!this.options["pawnfall"]) {
+            tr = {
+              c: color,
+              p: (initPiece != "!" ? piece : C.CannibalKingCode[piece])
+            };
+          }
+          let newMove = this.getBasicMove([x1, y1], [x2, y2], tr);
+          if (this.options["pawnfall"]) {
+            newMove.appear.shift();
+            newMove.pawnfall = true; //required in prePlay()
+          }
+          moreMoves.push(newMove);
+        }
+      });
+      Array.prototype.push.apply(moves, moreMoves);
+    }
+
+    if (
+      this.options["cannibal"] &&
+      this.options["rifle"] &&
+      this.pawnSpecs.promotions
+    ) {
+      // In this case a rifle-capture from last rank may promote a pawn
+      const lastRank = (color == "w" ? 0 : this.size.x - 1);
+      let newMoves = [];
+      moves.forEach(m => {
+        if (
+          m.start.x == lastRank &&
+          m.appear.length >= 1 &&
+          m.appear[0].p == "p" &&
+          m.appear[0].x == m.start.x &&
+          m.appear[0].y == m.start.y
+        ) {
+          const promotionPiece0 = this.pawnSpecs.promotions[0];
+          m.appear[0].p = this.pawnPromotions[0];
+          for (let i=1; i<this.pawnPromotions.length; i++) {
+            let newMv = JSON.parse(JSON.stringify(m));
+            newMv.appear[0].p = this.pawnSpecs.promotions[i];
+            newMoves.push(newMv);
+          }
         }
       });
+      Array.prototype.push.apply(moves, newMoves);
     }
+
     return moves;
   }
 
+  // NOTE: using special symbols to not interfere with variants' pieces codes
+  static get CannibalKings() {
+    return {
+      "!": "p",
+      "#": "r",
+      "$": "n",
+      "%": "b",
+      "*": "q"
+    };
+  }
+
+  static get CannibalKingCode() {
+    return {
+      "p": "!",
+      "r": "#",
+      "n": "$",
+      "b": "%",
+      "q": "*",
+      "k": "k"
+    };
+  }
+
+  isKing(symbol) {
+    return (
+      symbol == 'k' ||
+      (this.options["cannibal"] && C.CannibalKings[symbol])
+    );
+  }
+
   // For Madrasi:
   // (redefined in Baroque etc, where Madrasi condition doesn't make sense)
   isImmobilized([x, y]) {
     const color = this.getColor(x, y);
-    const oppCol = ChessRules.GetOppCol(color);
-    const piece = this.getPiece(x, y);
-    const stepSpec = this.pieces(color)[piece];
-    let [steps, range] = [stepSpec.attack || stepSpec.steps, stepSpec.range];
-    outerLoop: for (let step of steps) {
-      let [i, j] = [x + step[0], y + step[1]];
-      let stepCounter = 1;
-      while (this.onBoard(i, j) && this.board[i][j] == "") {
-        if (range <= stepCounter++) continue outerLoop;
-        i += step[0];
-        j = this.computeY(j + step[1]);
-      }
-      if (
-        this.onBoard(i, j) &&
-        this.getColor(i, j) == oppCol &&
-        this.getPiece(i, j) == piece
-      ) {
-        return true;
+    const oppCol = C.GetOppCol(color);
+    const piece = this.getPieceType(x, y); //ok not cannibal king
+    const stepSpec = this.pieces(color, x, y);
+    const attacks = stepSpec.attack || stepSpec.moves;
+    for (let a of attacks) {
+      outerLoop: for (let step of a.steps) {
+        let [i, j] = [x + step[0], y + step[1]];
+        let stepCounter = 1;
+        while (this.onBoard(i, j) && this.board[i][j] == "") {
+          if (a.range <= stepCounter++)
+            continue outerLoop;
+          i += step[0];
+          j = this.computeY(j + step[1]);
+        }
+        if (
+          this.onBoard(i, j) &&
+          this.getColor(i, j) == oppCol &&
+          this.getPieceType(i, j) == piece
+        ) {
+          return true;
+        }
       }
     }
     return false;
@@ -1276,74 +1463,108 @@ export default class ChessRules {
   // Generic method to find possible moves of "sliding or jumping" pieces
   getPotentialMovesOf(piece, [x, y]) {
     const color = this.getColor(x, y);
-    const stepSpec = this.pieces(color)[piece];
-    let [steps, range] = [stepSpec.steps, stepSpec.range];
+    const stepSpec = this.pieces(color, x, y)[piece];
     let moves = [];
     let explored = {}; //for Cylinder mode
-    outerLoop: for (let step of steps) {
-      let [i, j] = [x + step[0], this.computeY(y + step[1])];
-      let stepCounter = 1;
-      while (
-        this.onBoard(i, j) &&
-        this.board[i][j] == "" &&
-        !explored[i + "." + j]
-      ) {
-        explored[i + "." + j] = true;
-        moves.push(this.getBasicMove([x, y], [i, j]));
-        if (range <= stepCounter++) continue outerLoop;
-        i += step[0];
-        j = this.computeY(j + step[1]);
-      }
-      if (
-        this.onBoard(i, j) &&
-        (
-          !this.options["zen"] ||
-          this.getPiece(i, j) == ChessRules.KING ||
-          this.getColor(i, j) == color //OK for Recycle and Teleport
-        ) &&
-        this.canTake([x, y], [i, j]) &&
-        !explored[i + "." + j]
-      ) {
-        explored[i + "." + j] = true;
-        moves.push(this.getBasicMove([x, y], [i, j]));
+
+    const findAddMoves = (type, stepArray) => {
+      for (let s of stepArray) {
+        outerLoop: for (let step of s.steps) {
+          let [i, j] = [x + step[0], this.computeY(y + step[1])];
+          let stepCounter = 1;
+          while (this.onBoard(i, j) && this.board[i][j] == "") {
+            if (type != "attack" && !explored[i + "." + j]) {
+              explored[i + "." + j] = true;
+              moves.push(this.getBasicMove([x, y], [i, j]));
+            }
+            if (s.range <= stepCounter++)
+              continue outerLoop;
+            i += step[0];
+            j = this.computeY(j + step[1]);
+          }
+          if (!this.onBoard(i, j))
+            continue;
+          const pieceIJ = this.getPieceType(i, j);
+          if (
+            type != "moveonly" &&
+            !explored[i + "." + j] &&
+            (
+              !this.options["zen"] ||
+              pieceIJ == "k"
+            ) &&
+            (
+              this.canTake([x, y], [i, j]) ||
+              (
+                (this.options["recycle"] || this.options["teleport"]) &&
+                pieceIJ != "k"
+              )
+            )
+          ) {
+            explored[i + "." + j] = true;
+            moves.push(this.getBasicMove([x, y], [i, j]));
+          }
+        }
       }
-    }
+    };
+
+    const specialAttack = !!stepSpec.attack;
+    if (specialAttack)
+      findAddMoves("attack", stepSpec.attack);
+    findAddMoves(specialAttack ? "moveonly" : "all", stepSpec.moves);
     if (this.options["zen"])
-      Array.prototype.push.apply(moves, this.getZenCaptures(x, y));
+      Array.prototype.push.apply(moves, this.findCapturesOn([x, y], true));
     return moves;
   }
 
-  getZenCaptures(x, y) {
+  findCapturesOn([x, y], zen) {
     let moves = [];
     // Find reverse captures (opponent takes)
     const color = this.getColor(x, y);
-    const oppCol = ChessRules.GetOppCol(color);
-    const pieces = this.pieces(oppCol);
-    Object.keys(pieces).forEach(p => {
-      if (p == ChessRules.KING) return; //king isn't captured this way
-      const steps = pieces[p].attack || pieces[p].steps;
-      const range = pieces[p].range;
-      steps.forEach(s => {
-        // From x,y: revert step
-        let [i, j] = [x - s[0], this.computeY(y - s[1])];
-        let stepCounter = 1;
-        while (this.onBoard(i, j) && this.board[i][j] == "") {
-          if (range <= stepCounter++) return;
-          i -= s[0];
-          j = this.computeY(j - s[1]);
-        }
-        if (
-          this.onBoard(i, j) &&
-          this.getPiece(i, j) == p &&
-          this.getColor(i, j) == oppCol && //condition for Recycle & Teleport
-          this.canTake([i, j], [x, y])
-        ) {
-          if (this.getPiece(x, y) != ChessRules.PAWN)
-            moves.push(this.getBasicMove([x, y], [i, j]));
-          else this.addPawnMoves([x, y], [i, j], moves);
+    const pieceType = this.getPieceType(x, y);
+    const oppCol = C.GetOppCol(color);
+    for (let i=0; i<this.size.x; i++) {
+      for (let j=0; j<this.size.y; j++) {
+        if (this.board[i][j] != "" && this.canTake([i, j], [x, y])) {
+          const piece = this.getPieceType(i, j);
+          if (zen && C.CannibalKingCode[piece])
+            continue; //king not captured in this way
+          const stepSpec = this.pieces(oppCol, i, j)[piece];
+          const attacks = stepSpec.attack || stepSpec.moves;
+          for (let a of attacks) {
+            for (let s of a.steps) {
+              // Quick check: if step isn't compatible, don't even try
+              const rx = (x - i) / s[0],
+                    ry = (y - j) / s[1];
+              if (
+                (!Number.isFinite(rx) && !Number.isNaN(rx)) ||
+                (!Number.isFinite(ry) && !Number.isNaN(ry))
+              ) {
+                continue;
+              }
+              let distance = (Number.isNaN(rx) ? ry : rx);
+              // TODO: 1e-7 here is totally arbitrary
+              if (Math.abs(distance - Math.round(distance)) > 1e-7)
+                continue;
+              distance = Math.round(distance); //in case of (numerical...)
+              if (a.range < distance)
+                continue;
+              // Finally verify that nothing stand in-between
+              let [ii, jj] = [i + s[0], this.computeY(j + s[1])];
+              let stepCounter = 1;
+              while (this.onBoard(ii, jj) && this.board[ii][jj] == "") {
+                ii += s[0];
+                jj = this.computeY(jj + s[1]);
+              }
+              if (ii == x && jj == y) {
+                moves.push(this.getBasicMove([x, y], [i, j]));
+                if (!zen)
+                  return moves; //test for underCheck
+              }
+            }
+          }
         }
-      });
-    });
+      }
+    }
     return moves;
   }
 
@@ -1351,7 +1572,7 @@ export default class ChessRules {
   // tr: transformation
   getBasicMove([sx, sy], [ex, ey], tr) {
     const initColor = this.getColor(sx, sy);
-    const initPiece = this.board[sx][sy].charAt(1);
+    const initPiece = this.getPiece(sx, sy);
     const destColor = (this.board[ex][ey] != "" ? this.getColor(ex, ey) : "");
     let mv = new Move({
       appear: [],
@@ -1387,7 +1608,7 @@ export default class ChessRules {
           x: ex,
           y: ey,
           c: this.getColor(ex, ey),
-          p: this.board[ex][ey].charAt(1)
+          p: this.getPiece(ex, ey)
         })
       );
       if (this.options["rifle"])
@@ -1396,14 +1617,18 @@ export default class ChessRules {
         mv.capture = true;
       if (this.options["cannibal"] && destColor != initColor) {
         const lastIdx = mv.vanish.length - 1;
-        if (mv.appear.length >= 1) mv.appear[0].p = mv.vanish[lastIdx].p;
+        let trPiece = mv.vanish[lastIdx].p;
+        if (this.isKing(this.getPiece(sx, sy)))
+          trPiece = C.CannibalKingCode[trPiece];
+        if (mv.appear.length >= 1)
+          mv.appear[0].p = trPiece;
         else if (this.options["rifle"]) {
           mv.appear.unshift(
             new PiPo({
               x: sx,
               y: sy,
               c: initColor,
-              p: mv.vanish[lastIdx].p
+              p: trPiece
             })
           );
           mv.vanish.unshift(
@@ -1424,8 +1649,9 @@ export default class ChessRules {
   getEpSquare(moveOrSquare) {
     if (typeof moveOrSquare === "string") {
       const square = moveOrSquare;
-      if (square == "-") return undefined;
-      return ChessRules.SquareToCoords(square);
+      if (square == "-")
+        return undefined;
+      return C.SquareToCoords(square);
     }
     // Argument is a move:
     const move = moveOrSquare;
@@ -1435,8 +1661,8 @@ export default class ChessRules {
       s.y == e.y &&
       Math.abs(s.x - e.x) == 2 &&
       // Next conditions for variants like Atomic or Rifle, Recycle...
-      (move.appear.length > 0 && move.appear[0].p == ChessRules.PAWN) &&
-      (move.vanish.length > 0 && move.vanish[0].p == ChessRules.PAWN)
+      (move.appear.length > 0 && move.appear[0].p == "p") &&
+      (move.vanish.length > 0 && move.vanish[0].p == "p")
     ) {
       return {
         x: (s.x + e.x) / 2,
@@ -1447,9 +1673,10 @@ export default class ChessRules {
   }
 
   // Special case of en-passant captures: treated separately
-  getEnpassantCaptures([x, y], shiftX) {
+  getEnpassantCaptures([x, y]) {
     const color = this.getColor(x, y);
-    const oppCol = ChessRules.GetOppCol(color);
+    const shiftX = (color == 'w' ? -1 : 1);
+    const oppCol = C.GetOppCol(color);
     let enpassantMove = null;
     if (
       !!this.epSquare &&
@@ -1467,149 +1694,29 @@ export default class ChessRules {
     return !!enpassantMove ? [enpassantMove] : [];
   }
 
-  // Consider all potential promotions:
-  addPawnMoves([x1, y1], [x2, y2], moves, promotions) {
-    let finalPieces = [ChessRules.PAWN];
-    const color = this.getColor(x1, y1);
-    const lastRank = (color == "w" ? 0 : this.size.x - 1);
-    if (x2 == lastRank && (!this.options["rifle"] || this.board[x2][y2] == ""))
-    {
-      // promotions arg: special override for Hiddenqueen variant
-      if (promotions) finalPieces = promotions;
-      else if (this.pawnSpecs.promotions)
-        finalPieces = this.pawnSpecs.promotions;
-    }
-    for (let piece of finalPieces) {
-      const tr = (piece != ChessRules.PAWN ? { c: color, p: piece } : null);
-      moves.push(this.getBasicMove([x1, y1], [x2, y2], tr));
-    }
-  }
-
-  // What are the pawn moves from square x,y ?
-  getPotentialPawnMoves([x, y], promotions) {
-    const color = this.getColor(x, y); //this.turn doesn't work for Dark mode
-    const [sizeX, sizeY] = [this.size.x, this.size.y];
-    const pawnShiftX = this.pawnSpecs.directions[color];
-    const firstRank = (color == "w" ? sizeX - 1 : 0);
-    const forward = (color == 'w' ? -1 : 1);
-
-    // Pawn movements in shiftX direction:
-    const getPawnMoves = (shiftX) => {
-      let moves = [];
-      // NOTE: next condition is generally true (no pawn on last rank)
-      if (x + shiftX >= 0 && x + shiftX < sizeX) {
-        if (this.board[x + shiftX][y] == "") {
-          // One square forward (or backward)
-          this.addPawnMoves([x, y], [x + shiftX, y], moves, promotions);
-          // Next condition because pawns on 1st rank can generally jump
-          if (
-            this.pawnSpecs.twoSquares &&
-            (
-              (
-                color == 'w' &&
-                x >= this.size.x - 1 - this.pawnSpecs.initShift['w']
-              )
-              ||
-              (color == 'b' && x <= this.pawnSpecs.initShift['b'])
-            )
-          ) {
-            if (
-              shiftX == forward &&
-              this.board[x + 2 * shiftX][y] == ""
-            ) {
-              // Two squares jump
-              moves.push(this.getBasicMove([x, y], [x + 2 * shiftX, y]));
-              if (
-                this.pawnSpecs.threeSquares &&
-                this.board[x + 3 * shiftX, y] == ""
-              ) {
-                // Three squares jump
-                moves.push(this.getBasicMove([x, y], [x + 3 * shiftX, y]));
-              }
-            }
-          }
-        }
-        // Captures
-        if (this.pawnSpecs.canCapture) {
-          for (let shiftY of [-1, 1]) {
-            const yCoord = this.computeY(y + shiftY);
-            if (yCoord >= 0 && yCoord < sizeY) {
-              if (
-                this.board[x + shiftX][yCoord] != "" &&
-                this.canTake([x, y], [x + shiftX, yCoord]) &&
-                (
-                  !this.options["zen"] ||
-                  this.getPiece(x + shiftX, yCoord) == ChessRules.KING
-                )
-              ) {
-                this.addPawnMoves(
-                  [x, y], [x + shiftX, yCoord],
-                  moves, promotions
-                );
-              }
-              if (
-                this.pawnSpecs.captureBackward && shiftX == forward &&
-                x - shiftX >= 0 && x - shiftX < this.size.x &&
-                this.board[x - shiftX][yCoord] != "" &&
-                this.canTake([x, y], [x - shiftX, yCoord]) &&
-                (
-                  !this.options["zen"] ||
-                  this.getPiece(x + shiftX, yCoord) == ChessRules.KING
-                )
-              ) {
-                this.addPawnMoves(
-                  [x, y], [x - shiftX, yCoord],
-                  moves, promotions
-                );
-              }
-            }
-          }
-        }
-      }
-      return moves;
-    }
-
-    let pMoves = getPawnMoves(pawnShiftX);
-    if (this.pawnSpecs.bidirectional)
-      pMoves = pMoves.concat(getPawnMoves(-pawnShiftX));
-
-    if (this.hasEnpassant) {
-      // NOTE: backward en-passant captures are not considered
-      // because no rules define them (for now).
-      Array.prototype.push.apply(
-        pMoves,
-        this.getEnpassantCaptures([x, y], pawnShiftX)
-      );
-    }
-
-    if (this.options["zen"])
-      Array.prototype.push.apply(pMoves, this.getZenCaptures(x, y));
-
-    return pMoves;
-  }
-
   // "castleInCheck" arg to let some variants castle under check
   getCastleMoves([x, y], finalSquares, castleInCheck, castleWith) {
     const c = this.getColor(x, y);
 
     // Castling ?
-    const oppCol = ChessRules.GetOppCol(c);
+    const oppCol = C.GetOppCol(c);
     let moves = [];
     // King, then rook:
     finalSquares =
       finalSquares || [ [2, 3], [this.size.y - 2, this.size.y - 3] ];
-    const castlingKing = this.board[x][y].charAt(1);
+    const castlingKing = this.getPiece(x, y);
     castlingCheck: for (
       let castleSide = 0;
       castleSide < 2;
       castleSide++ //large, then small
     ) {
-      if (this.castleFlags[c][castleSide] >= this.size.y) continue;
+      if (this.castleFlags[c][castleSide] >= this.size.y)
+        continue;
       // If this code is reached, rook and king are on initial position
 
       // NOTE: in some variants this is not a rook
       const rookPos = this.castleFlags[c][castleSide];
-      const castlingPiece = this.board[x][rookPos].charAt(1);
+      const castlingPiece = this.getPiece(x, rookPos);
       if (
         this.board[x][rookPos] == "" ||
         this.getColor(x, rookPos) != c ||
@@ -1638,7 +1745,8 @@ export default class ChessRules {
       // Nothing on the path to the rook?
       step = (castleSide == 0 ? -1 : 1);
       for (i = y + step; i != rookPos; i += step) {
-        if (this.board[x][i] != "") continue castlingCheck;
+        if (this.board[x][i] != "")
+          continue castlingCheck;
       }
 
       // Nothing on final squares, except maybe king and castling rook?
@@ -1679,8 +1787,8 @@ export default class ChessRules {
           ],
           end:
             Math.abs(y - rookPos) <= 2
-              ? { x: x, y: rookPos }
-              : { x: x, y: y + 2 * (castleSide == 0 ? -1 : 1) }
+              ? {x: x, y: rookPos}
+              : {x: x, y: y + 2 * (castleSide == 0 ? -1 : 1)}
         })
       );
     }
@@ -1693,66 +1801,34 @@ export default class ChessRules {
 
   // Is (king at) given position under check by "color" ?
   underCheck([x, y], color) {
-    if (this.taking || this.options["dark"]) return false;
-    color = color || ChessRules.GetOppCol(this.getColor(x, y));
-    const pieces = this.pieces(color);
-    return Object.keys(pieces).some(p => {
-      return this.isAttackedBy([x, y], p, color, pieces[p]);
-    });
-  }
-
-  isAttackedBy([x, y], piece, color, stepSpec) {
-    const steps = stepSpec.attack || stepSpec.steps;
-    const range = stepSpec.range;
-    let explored = {}; //for Cylinder mode
-    outerLoop: for (let step of steps) {
-      let rx = x - step[0],
-          ry = this.computeY(y - step[1]);
-      let stepCounter = 1;
-      while (
-        this.onBoard(rx, ry) &&
-        this.board[rx][ry] == "" &&
-        !explored[rx + "." + ry]
-      ) {
-        explored[rx + "." + ry] = true;
-        if (range <= stepCounter++) continue outerLoop;
-        rx -= step[0];
-        ry = this.computeY(ry - step[1]);
-      }
-      if (
-        this.onBoard(rx, ry) &&
-        this.board[rx][ry] != "" &&
-        this.getPiece(rx, ry) == piece &&
-        this.getColor(rx, ry) == color &&
-        (!this.options["madrasi"] || !this.isImmobilized([rx, ry]))
-      ) {
-        return true;
-      }
-    }
-    return false;
+    if (this.options["taking"] || this.options["dark"])
+      return false;
+    return (this.findCapturesOn([x, y]).length >= 1);
   }
 
   // Stop at first king found (TODO: multi-kings)
   searchKingPos(color) {
     for (let i=0; i < this.size.x; i++) {
       for (let j=0; j < this.size.y; j++) {
-        if (this.board[i][j] == color + 'k') return [i, j];
+        if (this.getColor(i, j) == color && this.isKing(this.getPiece(i, j)))
+          return [i, j];
       }
     }
     return [-1, -1]; //king not found
   }
 
   filterValid(moves) {
-    if (moves.length == 0) return [];
+    if (moves.length == 0)
+      return [];
     const color = this.turn;
-    const oppCol = ChessRules.GetOppCol(color);
+    const oppCol = C.GetOppCol(color);
     if (this.options["balance"] && [1, 3].includes(this.movesCount)) {
       // Forbid moves either giving check or exploding opponent's king:
       const oppKingPos = this.searchKingPos(oppCol);
       moves = moves.filter(m => {
         if (
-          m.vanish.some(v => v.c == oppCol && v.p == ChessRules.KING) &&
-          m.appear.every(a => a.c != oppCol || a.p != ChessRUles.KING)
+          m.vanish.some(v => v.c == oppCol && v.p == "k") &&
+          m.appear.every(a => a.c != oppCol || a.p != "k")
         )
           return false;
         this.playOnBoard(m);
@@ -1761,7 +1837,8 @@ export default class ChessRules {
         return res;
       });
     }
-    if (this.taking || this.options["dark"]) return moves;
+    if (this.options["taking"] || this.options["dark"])
+      return moves;
     const kingPos = this.searchKingPos(color);
     let filtered = {}; //avoid re-checking similar moves (promotions...)
     return moves.filter(m => {
@@ -1770,13 +1847,18 @@ export default class ChessRules {
         this.playOnBoard(m);
         let square = kingPos,
             res = true; //a priori valid
-        if (m.vanish.some(v => v.p == ChessRules.KING && v.c == color)) {
+        if (m.vanish.some(v => {
+          return (v.p == "k" || C.CannibalKings[v.p]) && v.c == color;
+        })) {
           // Search king in appear array:
           const newKingIdx =
-            m.appear.findIndex(a => a.p == ChessRules.KING && a.c == color);
+            m.appear.findIndex(a => {
+              return (a.p == "k" || C.CannibalKings[a.p]) && a.c == color;
+            });
           if (newKingIdx >= 0)
             square = [m.appear[newKingIdx].x, m.appear[newKingIdx].y];
-          else res = false;
+          else
+            res = false;
         }
         res &&= !this.underCheck(square, oppCol);
         this.undoOnBoard(m);
@@ -1816,17 +1898,20 @@ export default class ChessRules {
     move.appear.concat(move.vanish).forEach(psq => {
       if (
         this.board[psq.x][psq.y] != "" &&
-        this.getPiece(psq.x, psq.y) == ChessRules.KING
+        this.getPieceType(psq.x, psq.y) == "k"
       ) {
         this.castleFlags[psq.c] = [this.size.y, this.size.y];
       }
       // NOTE: not "else if" because king can capture enemy rook...
-      let c = '';
-      if (psq.x == 0) c = 'b';
-      else if (psq.x == this.size.x - 1) c = 'w';
-      if (c != '') {
+      let c = "";
+      if (psq.x == 0)
+        c = "b";
+      else if (psq.x == this.size.x - 1)
+        c = "w";
+      if (c != "") {
         const fidx = this.castleFlags[c].findIndex(f => f == psq.y);
-        if (fidx >= 0) this.castleFlags[c][fidx] = this.size.y;
+        if (fidx >= 0)
+          this.castleFlags[c][fidx] = this.size.y;
       }
     });
   }
@@ -1834,7 +1919,7 @@ export default class ChessRules {
   prePlay(move) {
     if (
       typeof move.start.x == "number" &&
-      (!this.options["teleport"] || this.subTurn == 1)
+      (!this.options["teleport"] || this.subTurnTeleport == 1)
     ) {
       // OK, not a drop move
       if (
@@ -1845,25 +1930,33 @@ export default class ChessRules {
       ) {
         this.updateCastleFlags(move);
       }
-      const initSquare = ChessRules.CoordsToSquare(move.start);
+      const initSquare = C.CoordsToSquare(move.start);
       if (
         this.options["crazyhouse"] &&
         (!this.options["rifle"] || !move.capture)
       ) {
+        const destSquare = C.CoordsToSquare(move.end);
         if (this.ispawn[initSquare]) {
           delete this.ispawn[initSquare];
-          this.ispawn[ChessRules.CoordsToSquare(move.end)] = true;
+          this.ispawn[destSquare] = true;
+        }
+        else if (
+          move.vanish[0].p == "p" &&
+          move.appear[0].p != "p"
+        ) {
+          this.ispawn[destSquare] = true;
         }
         else if (
-          move.vanish[0].p == ChessRules.PAWN &&
-          move.appear[0].p != ChessRules.PAWN
+          this.ispawn[destSquare] &&
+          this.getColor(move.end.x, move.end.y) != move.vanish[0].c
         ) {
-          this.ispawn[ChessRules.CoordsToSquare(move.end)] = true;
+          move.vanish[1].p = "p";
+          delete this.ispawn[destSquare];
         }
       }
     }
     const minSize = Math.min(move.appear.length, move.vanish.length);
-    if (this.hasReserve) {
+    if (this.hasReserve && !move.pawnfall) {
       const color = this.turn;
       for (let i=minSize; i<move.appear.length; i++) {
         // Something appears = dropped on board (some exceptions, Chakart...)
@@ -1881,30 +1974,34 @@ export default class ChessRules {
 
   play(move) {
     this.prePlay(move);
-    if (this.hasEnpassant) this.epSquare = this.getEpSquare(move);
+    if (this.hasEnpassant)
+      this.epSquare = this.getEpSquare(move);
     this.playOnBoard(move);
     this.postPlay(move);
   }
 
   postPlay(move) {
     const color = this.turn;
-    const oppCol = ChessRules.GetOppCol(color);
-    if (this.options["dark"]) this.updateEnlightened(true);
+    const oppCol = C.GetOppCol(color);
+    if (this.options["dark"])
+      this.updateEnlightened();
     if (this.options["teleport"]) {
       if (
-        this.subTurn == 1 &&
+        this.subTurnTeleport == 1 &&
         move.vanish.length > move.appear.length &&
         move.vanish[move.vanish.length - 1].c == color
       ) {
         const v = move.vanish[move.vanish.length - 1];
         this.captured = {x: v.x, y: v.y, c: v.c, p: v.p};
-        this.subTurn = 2;
+        this.subTurnTeleport = 2;
         return;
       }
+      this.subTurnTeleport = 1;
       this.captured = null;
     }
     if (this.options["balance"]) {
-      if (![1, 3].includes(this.movesCount)) this.turn = oppCol;
+      if (![1, 3].includes(this.movesCount))
+        this.turn = oppCol;
     }
     else {
       if (
@@ -1916,7 +2013,13 @@ export default class ChessRules {
         (this.options["progressive"] && this.subTurn <= this.movesCount)
       ) {
         const oppKingPos = this.searchKingPos(oppCol);
-        if (oppKingPos[0] >= 0 && !this.underCheck(oppKingPos, color)) {
+        if (
+          oppKingPos[0] >= 0 &&
+          (
+            this.options["taking"] ||
+            !this.underCheck(oppKingPos, color)
+          )
+        ) {
           this.subTurn++;
           return;
         }
@@ -1933,16 +2036,19 @@ export default class ChessRules {
     for (let i = 0; i < this.size.x; i++) {
       for (let j = 0; j < this.size.y; j++) {
         if (this.board[i][j] != "" && this.getColor(i, j) == color) {
-          // TODO?: do not search all possible moves here
+          // NOTE: in fact searching for all potential moves from i,j.
+          //       I don't believe this is an issue, for now at least.
           const moves = this.getPotentialMovesFrom([i, j]);
-          if (moves.some(m => this.filterValid([m]).length >= 1)) return true;
+          if (moves.some(m => this.filterValid([m]).length >= 1))
+            return true;
         }
       }
     }
     if (this.hasReserve && this.reserve[color]) {
       for (let p of Object.keys(this.reserve[color])) {
         const moves = this.getDropMovesFrom([color, p]);
-        if (moves.some(m => this.filterValid([m]).length >= 1)) return true;
+        if (moves.some(m => this.filterValid([m]).length >= 1))
+          return true;
       }
     }
     return false;
@@ -1951,31 +2057,37 @@ export default class ChessRules {
   // What is the score ? (Interesting if game is over)
   getCurrentScore(move) {
     const color = this.turn;
-    const oppCol = ChessRules.GetOppCol(color);
+    const oppCol = C.GetOppCol(color);
     const kingPos = [this.searchKingPos(color), this.searchKingPos(oppCol)];
-    if (kingPos[0][0] < 0 && kingPos[1][0] < 0) return "1/2";
-    if (kingPos[0][0] < 0) return (color == "w" ? "0-1" : "1-0");
-    if (kingPos[1][0] < 0) return (color == "w" ? "1-0" : "0-1");
-    if (this.atLeastOneMove()) return "*";
+    if (kingPos[0][0] < 0 && kingPos[1][0] < 0)
+      return "1/2";
+    if (kingPos[0][0] < 0)
+      return (color == "w" ? "0-1" : "1-0");
+    if (kingPos[1][0] < 0)
+      return (color == "w" ? "1-0" : "0-1");
+    if (this.atLeastOneMove())
+      return "*";
     // No valid move: stalemate or checkmate?
-    if (!this.underCheck(kingPos, color)) return "1/2";
+    if (!this.underCheck(kingPos[0], color))
+      return "1/2";
     // OK, checkmate
     return (color == "w" ? "0-1" : "1-0");
   }
 
-  // NOTE: quite suboptimal for eg. Benedict (TODO?)
+  // NOTE: quite suboptimal for eg. Benedict (not a big deal I think)
   playVisual(move, r) {
     move.vanish.forEach(v => {
-      if (!this.enlightened || this.enlightened[v.x][v.y]) {
+      // TODO: next "if" shouldn't be required
+      if (this.g_pieces[v.x][v.y])
         this.g_pieces[v.x][v.y].remove();
-        this.g_pieces[v.x][v.y] = null;
-      }
+      this.g_pieces[v.x][v.y] = null;
     });
-    let container = document.getElementById(this.containerId);
-    if (!r) r = container.getBoundingClientRect();
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
+    if (!r)
+      r = chessboard.getBoundingClientRect();
     const pieceWidth = this.getPieceWidth(r.width);
     move.appear.forEach(a => {
-      if (this.enlightened && !this.enlightened[a.x][a.y]) return;
       this.g_pieces[a.x][a.y] = document.createElement("piece");
       this.g_pieces[a.x][a.y].classList.add(this.pieces()[a.p]["class"]);
       this.g_pieces[a.x][a.y].classList.add(a.c == "w" ? "white" : "black");
@@ -1983,13 +2095,17 @@ export default class ChessRules {
       this.g_pieces[a.x][a.y].style.height = pieceWidth + "px";
       const [ip, jp] = this.getPixelPosition(a.x, a.y, r);
       this.g_pieces[a.x][a.y].style.transform = `translate(${ip}px,${jp}px)`;
-      container.appendChild(this.g_pieces[a.x][a.y]);
+      if (this.enlightened && !this.enlightened[a.x][a.y])
+        this.g_pieces[a.x][a.y].classList.add("hidden");
+      chessboard.appendChild(this.g_pieces[a.x][a.y]);
     });
+    if (this.options["dark"])
+      this.graphUpdateEnlightened();
   }
 
   playPlusVisual(move, r) {
-    this.playVisual(move, r);
     this.play(move);
+    this.playVisual(move, r);
     this.afterPlay(move); //user method
   }
 
@@ -1998,12 +2114,14 @@ export default class ChessRules {
     let nbR = 0,
         ridx = 0;
     for (let pi of Object.keys(this.reserve[c])) {
-      if (this.reserve[c][pi] == 0) continue;
-      if (pi == p) ridx = nbR;
+      if (this.reserve[c][pi] == 0)
+        continue;
+      if (pi == p)
+        ridx = nbR;
       nbR++;
     }
     const rsqSize = this.getReserveSquareSize(r.width, nbR);
-    return [ridx * rsqSize, rsqSize]; //slightly inaccurate... TODO?
+    return [-ridx * rsqSize, rsqSize]; //slightly inaccurate... TODO?
   }
 
   animate(move, callback) {
@@ -2015,23 +2133,30 @@ export default class ChessRules {
     const dropMove = (typeof i1 == "string");
     const startArray = (dropMove ? this.r_pieces : this.g_pieces);
     let startPiece = startArray[i1][j1];
-    let container = document.getElementById(this.containerId);
+    // TODO: next "if" shouldn't be required
+    if (!startPiece) {
+      callback();
+      return;
+    }
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
     const clonePiece = (
       !dropMove &&
       this.options["rifle"] ||
-      (this.options["teleport"] && this.subTurn == 2)
+      (this.options["teleport"] && this.subTurnTeleport == 2)
     );
     if (clonePiece) {
       startPiece = startPiece.cloneNode();
-      if (this.options["rifle"]) startArray[i1][j1].style.opacity = "0";
-      if (this.options["teleport"] && this.subTurn == 2) {
+      if (this.options["rifle"])
+        startArray[i1][j1].style.opacity = "0";
+      if (this.options["teleport"] && this.subTurnTeleport == 2) {
         const pieces = this.pieces();
         const startCode = (dropMove ? j1 : this.getPiece(i1, j1));
         startPiece.classList.remove(pieces[startCode]["class"]);
         startPiece.classList.add(pieces[this.captured.p]["class"]);
         // Color: OK
       }
-      container.appendChild(startPiece);
+      chessboard.appendChild(startPiece);
     }
     const [i2, j2] = [move.end.x, move.end.y];
     let startCoords;
@@ -2041,25 +2166,33 @@ export default class ChessRules {
         this.size.y / 2 //not trying to be accurate here... (TODO?)
       ];
     }
-    else startCoords = [i1, j1];
-    const r = container.getBoundingClientRect();
+    else
+      startCoords = [i1, j1];
+    const r = chessboard.getBoundingClientRect();
     const arrival = this.getPixelPosition(i2, j2, r); //TODO: arrival on drop?
     let rs = [0, 0];
-    if (dropMove) rs = this.getReserveShift(i1, j1, r);
+    if (dropMove)
+      rs = this.getReserveShift(i1, j1, r);
     const distance =
       Math.sqrt((startCoords[0] - i2) ** 2 + (startCoords[1] - j2) ** 2);
     const maxDist = Math.sqrt((this.size.x - 1)** 2 + (this.size.y - 1) ** 2);
     const multFact = (distance - 1) / (maxDist - 1); //1 == minDist
     const duration = 0.2 + multFact * 0.3;
+    const initTransform = startPiece.style.transform;
     startPiece.style.transform =
       `translate(${arrival[0] + rs[0]}px, ${arrival[1] + rs[1]}px)`;
     startPiece.style.transitionDuration = duration + "s";
     setTimeout(
       () => {
         if (clonePiece) {
-          if (this.options["rifle"]) startArray[i1][j1].style.opacity = "1";
+          if (this.options["rifle"])
+            startArray[i1][j1].style.opacity = "1";
           startPiece.remove();
         }
+        else {
+          startPiece.style.transform = initTransform;
+          startPiece.style.transitionDuration = "0s";
+        }
         callback();
       },
       duration * 1000
@@ -2067,24 +2200,40 @@ export default class ChessRules {
   }
 
   playReceivedMove(moves, callback) {
-    if (!document.hasFocus()) {
-      window.onfocus = () => {
-        window.onfocus = undefined;
-        setTimeout(() => this.playReceivedMove(moves, callback), 700);
+    const launchAnimation = () => {
+      const r = container.querySelector(".chessboard").getBoundingClientRect();
+      const animateRec = i => {
+        this.animate(moves[i], () => {
+          this.playVisual(moves[i], r);
+          this.play(moves[i]);
+          if (i < moves.length - 1)
+            setTimeout(() => animateRec(i+1), 300);
+          else
+            callback();
+        });
       };
-      return;
-    }
-    const r =
-      document.getElementById(this.containerId).getBoundingClientRect();
-    const animateRec = i => {
-      this.animate(moves[i], () => {
-        this.playVisual(moves[i], r);
-        this.play(moves[i]);
-        if (i < moves.length - 1) setTimeout(() => animateRec(i+1), 300);
-        else callback();
-      });
+      animateRec(0);
+    };
+    // Delay if user wasn't focused:
+    const checkDisplayThenAnimate = (delay) => {
+      if (container.style.display == "none") {
+        alert("New move! Let's go back to game...");
+        document.getElementById("gameInfos").style.display = "none";
+        container.style.display = "block";
+        setTimeout(launchAnimation, 700);
+      }
+      else
+        setTimeout(launchAnimation, delay || 0);
     };
-    animateRec(0);
+    let container = document.getElementById(this.containerId);
+    if (document.hidden) {
+      document.onvisibilitychange = () => {
+        document.onvisibilitychange = undefined;
+        checkDisplayThenAnimate(700);
+      };
+    }
+    else
+      checkDisplayThenAnimate();
   }
 
 };