X-Git-Url: https://git.auder.net/?p=xogo.git;a=blobdiff_plain;f=base_rules.js;h=8ad0894e2972c074d8474844e15d52511fefc7d8;hp=e7d58b26ebfa2c5b7470ea13cf4213cf4cf7bbae;hb=3b641716d7e86d9f1b39d1e046ce197e6b5a8075;hpb=449d72e350051d3ddb86a360c7bb4a4327cbeb75

diff --git a/base_rules.js b/base_rules.js
index e7d58b2..8ad0894 100644
--- a/base_rules.js
+++ b/base_rules.js
@@ -29,16 +29,18 @@ export default class ChessRules {
           {label: "Asymmetric random", value: 2}
         ]
       }],
-      check: [
+      input: [
         {
           label: "Capture king",
-          defaut: false,
-          variable: "taking"
+          variable: "taking",
+          type: "checkbox",
+          defaut: false
         },
         {
           label: "Falling pawn",
-          defaut: false,
-          variable: "pawnfall"
+          variable: "pawnfall",
+          type: "checkbox",
+          defaut: false
         }
       ],
       // Game modifiers (using "elementary variants"). Default: false
@@ -85,6 +87,10 @@ export default class ChessRules {
       (!!this.options["recycle"] && !this.options["teleport"])
     );
   }
+  // Some variants do not store reserve state (Align4, Chakart...)
+  get hasReserveFen() {
+    return this.hasReserve;
+  }
 
   get noAnimate() {
     return !!this.options["dark"];
@@ -98,7 +104,7 @@ export default class ChessRules {
       this.options["teleport"] && this.subTurnTeleport == 2 &&
       this.board[coords.x][coords.y] == ""
     ) {
-      return new Move({
+      let res = new Move({
         start: {x: this.captured.x, y: this.captured.y},
         appear: [
           new PiPo({
@@ -108,9 +114,10 @@ export default class ChessRules {
             p: this.captured.p
           })
         ],
-        vanish: [],
-        drag: {c: this.captured.c, p: this.captured.p}
+        vanish: []
       });
+      res.drag = {c: this.captured.c, p: this.captured.p};
+      return res;
     }
     return null;
   }
@@ -118,13 +125,13 @@ export default class ChessRules {
   ////////////////////
   // COORDINATES UTILS
 
-  // a3 --> {x:10, y:3}
+  // 3a --> {x:3, y:10}
   static SquareToCoords(sq) {
     return ArrayFun.toObject(["x", "y"],
                              [0, 1].map(i => parseInt(sq[i], 36)));
   }
 
-  // {x:1, y:12} --> 1c
+  // {x:11, y:12} --> bc
   static CoordsToSquare(cd) {
     return Object.values(cd).map(c => c.toString(36)).join("");
   }
@@ -162,18 +169,16 @@ export default class ChessRules {
 
   // Turn "wb" into "B" (for FEN)
   board2fen(b) {
-    return b[0] == "w" ? b[1].toUpperCase() : b[1];
+    return (b[0] == "w" ? b[1].toUpperCase() : b[1]);
   }
 
   // Turn "p" into "bp" (for board)
   fen2board(f) {
-    return f.charCodeAt(0) <= 90 ? "w" + f.toLowerCase() : "b" + f;
+    return (f.charCodeAt(0) <= 90 ? "w" + f.toLowerCase() : "b" + f);
   }
 
   // Setup the initial random-or-not (asymmetric-or-not) position
   genRandInitFen(seed) {
-    Random.setSeed(seed);
-
     let fen, flags = "0707";
     if (!this.options.randomness)
       // Deterministic:
@@ -181,7 +186,8 @@ export default class ChessRules {
 
     else {
       // Randomize
-      let pieces = { w: new Array(8), b: new Array(8) };
+      Random.setSeed(seed);
+      let pieces = {w: new Array(8), b: new Array(8)};
       flags = "";
       // Shuffle pieces on first (and last rank if randomness == 2)
       for (let c of ["w", "b"]) {
@@ -280,7 +286,7 @@ export default class ChessRules {
       parts.push(`"flags":"${this.getFlagsFen()}"`);
     if (this.hasEnpassant)
       parts.push(`"enpassant":"${this.getEnpassantFen()}"`);
-    if (this.hasReserve)
+    if (this.hasReserveFen)
       parts.push(`"reserve":"${this.getReserveFen()}"`);
     if (this.options["crazyhouse"])
       parts.push(`"ispawn":"${this.getIspawnFen()}"`);
@@ -289,19 +295,20 @@ export default class ChessRules {
     return fen;
   }
 
+  static FenEmptySquares(count) {
+    // if more than 9 consecutive free spaces, break the integer,
+    // otherwise FEN parsing will fail.
+    if (count <= 9)
+      return count;
+    // Most boards of size < 18:
+    if (count <= 18)
+      return "9" + (count - 9);
+    // Except Gomoku:
+    return "99" + (count - 18);
+  }
+
   // Position part of the FEN string
   getPosition() {
-    const format = (count) => {
-      // if more than 9 consecutive free spaces, break the integer,
-      // otherwise FEN parsing will fail.
-      if (count <= 9)
-        return count;
-      // Most boards of size < 18:
-      if (count <= 18)
-        return "9" + (count - 9);
-      // Except Gomoku:
-      return "99" + (count - 18);
-    };
     let position = "";
     for (let i = 0; i < this.size.y; i++) {
       let emptyCount = 0;
@@ -311,7 +318,7 @@ export default class ChessRules {
         else {
           if (emptyCount > 0) {
             // Add empty squares in-between
-            position += format(emptyCount);
+            position += C.FenEmptySquares(emptyCount);
             emptyCount = 0;
           }
           position += this.board2fen(this.board[i][j]);
@@ -319,7 +326,7 @@ export default class ChessRules {
       }
       if (emptyCount > 0)
         // "Flush remainder"
-        position += format(emptyCount);
+        position += C.FenEmptySquares(emptyCount);
       if (i < this.size.y - 1)
         position += "/"; //separate rows
     }
@@ -370,6 +377,14 @@ export default class ChessRules {
 
   constructor(o) {
     this.options = o.options;
+    // Fill missing options (always the case if random challenge)
+    (V.Options.select || []).concat(V.Options.input || []).forEach(opt => {
+      if (this.options[opt.variable] === undefined)
+        this.options[opt.variable] = opt.defaut;
+    });
+    if (o.genFenOnly)
+      // This object will be used only for initial FEN generation
+      return;
     this.playerColor = o.color;
     this.afterPlay = o.afterPlay; //trigger some actions after playing a move
 
@@ -455,7 +470,7 @@ export default class ChessRules {
     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]);
+            y = this.getY(this.epSquare.y - step[1]);
       if (
         this.onBoard(x, y) &&
         this.getColor(x, y) == this.playerColor &&
@@ -519,6 +534,22 @@ export default class ChessRules {
     return `${this.containerId}|rnum-${color}${piece}`;
   }
 
+  static AddClass_es(piece, class_es) {
+    if (!Array.isArray(class_es))
+      class_es = [class_es];
+    class_es.forEach(cl => {
+      piece.classList.add(cl);
+    });
+  }
+
+  static RemoveClass_es(piece, class_es) {
+    if (!Array.isArray(class_es))
+      class_es = [class_es];
+    class_es.forEach(cl => {
+      piece.classList.remove(cl);
+    });
+  }
+
   graphicalInit() {
     // NOTE: not window.onresize = this.re_drawBoardElts because scope (this)
     window.onresize = () => this.re_drawBoardElements();
@@ -526,7 +557,6 @@ export default class ChessRules {
     this.initMouseEvents();
     const chessboard =
       document.getElementById(this.containerId).querySelector(".chessboard");
-    new ResizeObserver(this.rescale).observe(chessboard);
   }
 
   re_drawBoardElements() {
@@ -549,7 +579,7 @@ export default class ChessRules {
       cbHeight = Math.min(window.innerHeight, 767);
       cbWidth = cbHeight * this.size.ratio;
     }
-    if (this.reserve) {
+    if (this.hasReserve) {
       const sqSize = cbWidth / this.size.y;
       // NOTE: allocate space for reserves (up/down) even if they are empty
       // Cannot use getReserveSquareSize() here, but sqSize is an upper bound.
@@ -581,8 +611,7 @@ export default class ChessRules {
     let board = `
       <svg
         viewBox="0 0 80 80"
-        class="chessboard_SVG">
-      <g>`;
+        class="chessboard_SVG">`;
     for (let i=0; i < this.size.x; i++) {
       for (let j=0; j < this.size.y; j++) {
         const ii = (flipped ? this.size.x - 1 - i : i);
@@ -591,16 +620,18 @@ export default class ChessRules {
         if (this.enlightened && !this.enlightened[ii][jj])
           classes += " in-shadow";
         // NOTE: x / y reversed because coordinates system is reversed.
-        board += `<rect
-          class="${classes}"
-          id="${this.coordsToId({x: ii, y: jj})}"
-          width="10"
-          height="10"
-          x="${10*j}"
-          y="${10*i}" />`;
+        board += `
+          <rect
+            class="${classes}"
+            id="${this.coordsToId({x: ii, y: jj})}"
+            width="10"
+            height="10"
+            x="${10*j}"
+            y="${10*i}"
+          />`;
       }
     }
-    board += "</g></svg>";
+    board += "</svg>";
     return board;
   }
 
@@ -634,49 +665,46 @@ export default class ChessRules {
           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"]);
+          C.AddClass_es(this.g_pieces[i][j], this.pieces()[piece]["class"]);
           this.g_pieces[i][j].classList.add(C.GetColorClass(color));
           this.g_pieces[i][j].style.width = pieceWidth + "px";
           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)`;
+          let [ip, jp] = this.getPixelPosition(i, j, r);
+          // Translate coordinates to use chessboard as reference:
+          this.g_pieces[i][j].style.transform =
+            `translate(${ip - r.x}px,${jp - r.y}px)`;
           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)
+    if (this.hasReserve)
       this.re_drawReserve(['w', 'b'], r);
   }
 
-  // NOTE: assume !!this.reserve
+  // NOTE: assume this.reserve != null
   re_drawReserve(colors, r) {
     if (this.r_pieces) {
       // Remove (old) reserve pieces
       for (let c of colors) {
-        if (!this.reserve[c])
-          continue;
-        Object.keys(this.reserve[c]).forEach(p => {
-          if (this.r_pieces[c][p]) {
-            this.r_pieces[c][p].remove();
-            delete this.r_pieces[c][p];
-            const numId = this.getReserveNumId(c, p);
-            document.getElementById(numId).remove();
-          }
+        Object.keys(this.r_pieces[c]).forEach(p => {
+          this.r_pieces[c][p].remove();
+          delete this.r_pieces[c][p];
+          const numId = this.getReserveNumId(c, p);
+          document.getElementById(numId).remove();
         });
-        let reservesDiv = document.getElementById("reserves_" + c);
-        if (reservesDiv)
-          reservesDiv.remove();
       }
     }
     else
-      this.r_pieces = { 'w': {}, 'b': {} };
-    let chessboard = 
-      document.getElementById(this.containerId).querySelector(".chessboard");
+      this.r_pieces = { w: {}, b: {} };
+    let container = document.getElementById(this.containerId);
     if (!r)
-      r = chessboard.getBoundingClientRect();
+      r = container.querySelector(".chessboard").getBoundingClientRect();
     for (let c of colors) {
+      let reservesDiv = document.getElementById("reserves_" + c);
+      if (reservesDiv)
+        reservesDiv.remove();
       if (!this.reserve[c])
         continue;
       const nbR = this.getNbReservePieces(c);
@@ -694,7 +722,7 @@ export default class ChessRules {
       // NOTE: +1 fix display bug on Firefox at least
       rcontainer.style.width = (nbR * sqResSize + 1) + "px";
       rcontainer.style.height = sqResSize + "px";
-      chessboard.appendChild(rcontainer);
+      container.appendChild(rcontainer);
       for (let p of Object.keys(this.reserve[c])) {
         if (this.reserve[c][p] == 0)
           continue;
@@ -705,8 +733,7 @@ export default class ChessRules {
         r_cell.style.height = sqResSize + "px";
         rcontainer.appendChild(r_cell);
         let piece = document.createElement("piece");
-        const pieceSpec = this.pieces()[p];
-        piece.classList.add(pieceSpec["class"]);
+        C.AddClass_es(piece, this.pieces()[p]["class"]);
         piece.classList.add(C.GetColorClass(c));
         piece.style.width = "100%";
         piece.style.height = "100%";
@@ -748,13 +775,13 @@ export default class ChessRules {
     for (let x=0; x<this.size.x; x++) {
       for (let y=0; y<this.size.y; y++) {
         if (!this.enlightened[x][y] && this.oldEnlightened[x][y]) {
-          let elt = document.getElementById(this.coordsToId(x, y));
+          let elt = document.getElementById(this.coordsToId({x: x, y: y}));
           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] && !this.oldEnlightened[x][y]) {
-          let elt = document.getElementById(this.coordsToId(x, y));
+          let elt = document.getElementById(this.coordsToId({x: x, y: y}));
           elt.classList.remove("in-shadow");
           if (this.g_pieces[x][y])
             this.g_pieces[x][y].classList.remove("hidden");
@@ -763,42 +790,48 @@ export default class ChessRules {
     }
   }
 
-  // After resize event: no need to destroy/recreate pieces
-  rescale() {
-    const container = document.getElementById(this.containerId);
-    if (!container)
-      return; //useful at initial loading
-    let chessboard = container.querySelector(".chessboard");
+  // Resize board: no need to destroy/recreate pieces
+  rescale(mode) {
+    let chessboard =
+      document.getElementById(this.containerId).querySelector(".chessboard");
     const r = chessboard.getBoundingClientRect();
-    const newRatio = r.width / r.height;
-    let newWidth = r.width,
-        newHeight = r.height;
-    if (newRatio > this.size.ratio) {
-      newWidth = r.height * this.size.ratio;
-      chessboard.style.width = newWidth + "px";
+    const multFact = (mode == "up" ? 1.05 : 0.95);
+    let [newWidth, newHeight] = [multFact * r.width, multFact * r.height];
+    // Stay in window:
+    if (newWidth > window.innerWidth) {
+      newWidth = window.innerWidth;
+      newHeight = newWidth / this.size.ratio;
     }
-    else if (newRatio < this.size.ratio) {
-      newHeight = r.width / this.size.ratio;
-      chessboard.style.height = newHeight + "px";
+    if (newHeight > window.innerHeight) {
+      newHeight = window.innerHeight;
+      newWidth = newHeight * this.size.ratio;
     }
+    chessboard.style.width = newWidth + "px";
+    chessboard.style.height = newHeight + "px";
     const newX = (window.innerWidth - newWidth) / 2;
     chessboard.style.left = newX + "px";
     const newY = (window.innerHeight - newHeight) / 2;
     chessboard.style.top = newY + "px";
-    const newR = { x: newX, y: newY, width: newWidth, height: newHeight };
+    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.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";
-          const [ip, jp] = this.getPixelPosition(i, j, newR);
-          this.g_pieces[i][j].style.transform = `translate(${ip}px,${jp}px)`;
+    // NOTE: next "if" for variants which use squares filling
+    // instead of "physical", moving pieces
+    if (this.g_pieces) {
+      for (let i=0; i < this.size.x; i++) {
+        for (let j=0; j < this.size.y; 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";
+            const [ip, jp] = this.getPixelPosition(i, j, newR);
+            // Translate coordinates to use chessboard as reference:
+            this.g_pieces[i][j].style.transform =
+              `translate(${ip - newX}px,${jp - newY}px)`;
+          }
         }
       }
     }
-    if (this.reserve)
+    if (this.hasReserve)
       this.rescaleReserve(newR);
   }
 
@@ -830,7 +863,7 @@ export default class ChessRules {
     }
   }
 
-  // Return the absolute pixel coordinates (on board) given current position.
+  // Return the absolute pixel coordinates given current position.
   // Our coordinate system differs from CSS one (x <--> y).
   // We return here the CSS coordinates (more useful).
   getPixelPosition(i, j, r) {
@@ -850,12 +883,12 @@ export default class ChessRules {
       x = (flipped ? this.size.y - 1 - j : j) * sqSize;
       y = (flipped ? this.size.x - 1 - i : i) * sqSize;
     }
-    return [x, y];
+    return [r.x + x, r.y + y];
   }
 
   initMouseEvents() {
-    let chessboard =
-      document.getElementById(this.containerId).querySelector(".chessboard");
+    let container = document.getElementById(this.containerId);
+    let chessboard = container.querySelector(".chessboard");
 
     const getOffset = e => {
       if (e.clientX)
@@ -876,8 +909,8 @@ export default class ChessRules {
     const centerOnCursor = (piece, e) => {
       const centerShift = this.getPieceWidth(r.width) / 2;
       const offset = getOffset(e);
-      piece.style.left = (offset.x - r.x - centerShift) + "px";
-      piece.style.top = (offset.y - r.y - centerShift) + "px";
+      piece.style.left = (offset.x - centerShift) + "px";
+      piece.style.top = (offset.y - centerShift) + "px";
     }
 
     let start = null,
@@ -910,7 +943,7 @@ export default class ChessRules {
             curPiece.style.width = pieceWidth + "px";
             curPiece.style.height = pieceWidth + "px";
             centerOnCursor(curPiece, e);
-            chessboard.appendChild(curPiece);
+            container.appendChild(curPiece);
             startPiece.style.opacity = "0.4";
             chessboard.style.cursor = "none";
           }
@@ -929,11 +962,6 @@ export default class ChessRules {
     };
 
     const mouseup = (e) => {
-      const newR = chessboard.getBoundingClientRect();
-      if (newR.width != r.width || newR.height != r.height) {
-        this.rescale();
-        return;
-      }
       if (!start)
         return;
       const [x, y] = [start.x, start.y];
@@ -962,6 +990,8 @@ export default class ChessRules {
       document.addEventListener("mousedown", mousedown);
       document.addEventListener("mousemove", mousemove);
       document.addEventListener("mouseup", mouseup);
+      document.addEventListener("wheel",
+        (e) => this.rescale(e.deltaY < 0 ? "up" : "down"));
     }
     if ('ontouchstart' in window) {
       // https://stackoverflow.com/a/42509310/12660887
@@ -1002,8 +1032,8 @@ export default class ChessRules {
       choice.style.backgroundColor = "lightyellow";
       choice.onclick = () => callback(moves[i]);
       const piece = document.createElement("piece");
-      const pieceSpec = this.pieces()[moves[i].appear[0].p];
-      piece.classList.add(pieceSpec["class"]);
+      const cdisp = moves[i].choice || moves[i].appear[0].p;
+      C.AddClass_es(piece, this.pieces()[cdisp]["class"]);
       piece.classList.add(C.GetColorClass(color));
       piece.style.width = "100%";
       piece.style.height = "100%";
@@ -1031,7 +1061,11 @@ export default class ChessRules {
   }
 
   static GetColorClass(c) {
-    return (c == 'w' ? "white" : "black");
+    if (c == 'w')
+      return "white";
+    if (c == 'b')
+      return "black";
+    return "other-color"; //unidentified color
   }
 
   // Assume square i,j isn't empty
@@ -1043,7 +1077,7 @@ export default class ChessRules {
 
   // Piece type on square (i,j)
   getPieceType(i, j) {
-    const p = (typeof i == "string" ? j : this.board[i][j].charAt(1));
+    const p = this.getPiece(i, j);
     return C.CannibalKings[p] || p; //a cannibal king move as...
   }
 
@@ -1065,13 +1099,7 @@ export default class ChessRules {
 
   // Am I allowed to move thing at square x,y ?
   canIplay(x, y) {
-    return (
-      this.playerColor == this.turn &&
-      (
-        (typeof x == "number" && this.getColor(x, y) == this.turn) ||
-        (typeof x == "string" && x == this.turn) //reserve
-      )
-    );
+    return (this.playerColor == this.turn && this.getColor(x, y) == this.turn);
   }
 
   ////////////////////////
@@ -1079,7 +1107,8 @@ export default class ChessRules {
 
   pieces(color, x, y) {
     const pawnShift = (color == "w" ? -1 : 1);
-    const initRank = ((color == 'w' && x == 6) || (color == 'b' && x == 1));
+    // NOTE: jump 2 squares from first rank (pawns can be here sometimes)
+    const initRank = ((color == 'w' && x >= 6) || (color == 'b' && x <= 1));
     return {
       'p': {
         "class": "pawn",
@@ -1161,7 +1190,7 @@ export default class ChessRules {
   // MOVES GENERATION
 
   // For Cylinder: get Y coordinate
-  computeY(y) {
+  getY(y) {
     if (!this.options["cylinder"])
       return y;
     let res = y % this.size.y;
@@ -1182,13 +1211,13 @@ export default class ChessRules {
           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 [ii, jj] = [i + step[0], this.getY(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]);
+                jj = this.getY(jj + step[1]);
               }
               if (
                 this.onBoard(ii, jj) &&
@@ -1209,7 +1238,7 @@ export default class ChessRules {
 
   getDropMovesFrom([c, p]) {
     // NOTE: by design, this.reserve[c][p] >= 1 on user click
-    // (but not necessarily otherwise)
+    // (but not necessarily otherwise: atLeastOneMove() etc)
     if (this.reserve[c][p] == 0)
       return [];
     let moves = [];
@@ -1289,7 +1318,7 @@ export default class ChessRules {
       this.options["rifle"]
     ) {
       // In this case a rifle-capture from last rank may promote a pawn
-      this.riflePromotePostProcess(moves);
+      this.riflePromotePostProcess(moves, color);
     }
 
     return moves;
@@ -1325,7 +1354,7 @@ export default class ChessRules {
         ];
         for (let step of steps) {
           let x = m.end.x + step[0];
-          let y = this.computeY(m.end.y + step[1]);
+          let y = this.getY(m.end.y + step[1]);
           if (
             this.onBoard(x, y) &&
             this.board[x][y] != "" &&
@@ -1342,7 +1371,7 @@ export default class ChessRules {
           }
         }
         if (!this.options["rifle"])
-          m.appear.pop(); //nothin appears
+          m.appear.pop(); //nothing appears
       }
     });
   }
@@ -1352,7 +1381,6 @@ export default class ChessRules {
     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 = (
@@ -1361,41 +1389,37 @@ export default class ChessRules {
       );
       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;
+      if (this.options["pawnfall"]) {
+        m.appear.shift();
+        return;
       }
+      let finalPieces = ["p"];
+      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])
-          };
-        }
+        const 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);
   }
 
-  riflePromotePostProcess(moves) {
+  riflePromotePostProcess(moves, color) {
     const lastRank = (color == "w" ? 0 : this.size.x - 1);
     let newMoves = [];
     moves.forEach(m => {
@@ -1406,7 +1430,6 @@ export default class ChessRules {
         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));
@@ -1425,7 +1448,8 @@ export default class ChessRules {
       "#": "r",
       "$": "n",
       "%": "b",
-      "*": "q"
+      "*": "q",
+      "k": "k"
     };
   }
 
@@ -1441,10 +1465,7 @@ export default class ChessRules {
   }
 
   isKing(symbol) {
-    return (
-      symbol == 'k' ||
-      (this.options["cannibal"] && C.CannibalKings[symbol])
-    );
+    return !!C.CannibalKings[symbol];
   }
 
   // For Madrasi:
@@ -1465,7 +1486,7 @@ export default class ChessRules {
           if (a.range <= stepCounter++)
             continue outerLoop;
           i += step[0];
-          j = this.computeY(j + step[1]);
+          j = this.getY(j + step[1]);
         }
         if (
           this.onBoard(i, j) &&
@@ -1479,28 +1500,59 @@ export default class ChessRules {
     return false;
   }
 
+  canStepOver(i, j) {
+    // In some variants, objects on boards don't stop movement (Chakart)
+    return this.board[i][j] == "";
+  }
+
   // 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, x, y)[piece];
     let moves = [];
-    let explored = {}; //for Cylinder mode
+    // Next 3 for Cylinder mode:
+    let explored = {};
+    let segments = [];
+    let segStart = [];
+
+    const addMove = (start, end) => {
+      let newMove = this.getBasicMove(start, end);
+      if (segments.length > 0) {
+        newMove.segments = JSON.parse(JSON.stringify(segments));
+        newMove.segments.push([[segStart[0], segStart[1]], [end[0], end[1]]]);
+      }
+      moves.push(newMove);
+    };
 
     const findAddMoves = (type, stepArray) => {
       for (let s of stepArray) {
-        // TODO: if jump in y (computeY, Cylinder), move.segments
         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]) {
+          segments = [];
+          segStart = [x, y];
+          let [i, j] = [x, y];
+          let stepCounter = 0;
+          while (
+            this.onBoard(i, j) &&
+            (this.canStepOver(i, j) || (i == x && j == y))
+          ) {
+            if (
+              type != "attack" &&
+              !explored[i + "." + j] &&
+              (i != x || j != y)
+            ) {
               explored[i + "." + j] = true;
-              moves.push(this.getBasicMove([x, y], [i, j]));
+              addMove([x, y], [i, j]);
             }
             if (s.range <= stepCounter++)
               continue outerLoop;
+            const oldIJ = [i, j];
             i += step[0];
-            j = this.computeY(j + step[1]);
+            j = this.getY(j + step[1]);
+            if (Math.abs(j - oldIJ[1]) > 1) {
+              // Boundary between segments (cylinder mode)
+              segments.push([[segStart[0], segStart[1]], oldIJ]);
+              segStart = [i, j];
+            }
           }
           if (!this.onBoard(i, j))
             continue;
@@ -1521,7 +1573,7 @@ export default class ChessRules {
             )
           ) {
             explored[i + "." + j] = true;
-            moves.push(this.getBasicMove([x, y], [i, j]));
+            addMove([x, y], [i, j]);
           }
         }
       }
@@ -1531,28 +1583,29 @@ export default class ChessRules {
     if (specialAttack)
       findAddMoves("attack", stepSpec.attack);
     findAddMoves(specialAttack ? "moveonly" : "all", stepSpec.moves);
-    if (this.options["zen"])
-      Array.prototype.push.apply(moves, this.findCapturesOn([x, y], true));
+    if (this.options["zen"]) {
+      Array.prototype.push.apply(moves,
+                                 this.findCapturesOn([x, y], {zen: true}));
+    }
     return moves;
   }
 
-  findCapturesOn([x, y], zen) {
+  // Search for enemy (or not) pieces attacking [x, y]
+  findCapturesOn([x, y], args) {
     let moves = [];
-    // Find reverse captures (opponent takes)
-    const color = this.getColor(x, y);
-    const pieceType = this.getPieceType(x, y);
-    const oppCol = C.GetOppCol(color);
+    if (!args.oppCol)
+      args.oppCol = C.GetOppCol(this.getColor(x, y) || this.turn);
     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]) &&
+          this.getColor(i, j) == args.oppCol &&
           !this.isImmobilized([i, j])
         ) {
-          const piece = this.getPieceType(i, j);
-          if (zen && C.CannibalKingCode[piece])
+          if (args.zen && this.isKing(this.getPiece(i, j)))
             continue; //king not captured in this way
-          const stepSpec = this.pieces(oppCol, i, j)[piece];
+          const stepSpec =
+            this.pieces(args.oppCol, i, j)[this.getPieceType(i, j)];
           const attacks = stepSpec.attack || stepSpec.moves;
           for (let a of attacks) {
             for (let s of a.steps) {
@@ -1560,15 +1613,23 @@ export default class ChessRules {
               if (!C.CompatibleStep([i, j], [x, y], s, a.range))
                 continue;
               // Finally verify that nothing stand in-between
-              let [ii, jj] = [i + s[0], this.computeY(j + s[1])];
+              let [ii, jj] = [i + s[0], this.getY(j + s[1])];
               let stepCounter = 1;
-              while (this.onBoard(ii, jj) && this.board[ii][jj] == "") {
+              while (
+                this.onBoard(ii, jj) &&
+                this.board[ii][jj] == "" &&
+                (ii != x || jj != y) //condition to attack empty squares too
+              ) {
                 ii += s[0];
-                jj = this.computeY(jj + s[1]);
+                jj = this.getY(jj + s[1]);
               }
               if (ii == x && jj == y) {
-                moves.push(this.getBasicMove([x, y], [i, j]));
-                if (!zen)
+                if (args.zen)
+                  // Reverse capture:
+                  moves.push(this.getBasicMove([x, y], [i, j]));
+                else
+                  moves.push(this.getBasicMove([i, j], [x, y]));
+                if (args.one)
                   return moves; //test for underCheck
               }
             }
@@ -1641,10 +1702,6 @@ export default class ChessRules {
           p: this.getPiece(ex, ey)
         })
       );
-      if (this.options["rifle"])
-        // Rifle captures are tricky in combination with Atomic etc,
-        // so it's useful to mark the move :
-        mv.capture = true;
       if (this.options["cannibal"] && destColor != initColor) {
         const lastIdx = mv.vanish.length - 1;
         let trPiece = mv.vanish[lastIdx].p;
@@ -1711,7 +1768,7 @@ export default class ChessRules {
     if (
       !!this.epSquare &&
       this.epSquare.x == x + shiftX &&
-      Math.abs(this.computeY(this.epSquare.y - y)) == 1 &&
+      Math.abs(this.getY(this.epSquare.y - y)) == 1 &&
       this.getColor(x, this.epSquare.y) == oppCol //Doublemove guard...
     ) {
       const [epx, epy] = [this.epSquare.x, this.epSquare.y];
@@ -1829,11 +1886,13 @@ export default class ChessRules {
   ////////////////////
   // MOVES VALIDATION
 
-  // Is (king at) given position under check by "color" ?
-  underCheck([x, y], color) {
+  // Is (king at) given position under check by "oppCol" ?
+  underCheck([x, y], oppCol) {
     if (this.options["taking"] || this.options["dark"])
       return false;
-    return (this.findCapturesOn([x, y]).length >= 1);
+    return (
+      this.findCapturesOn([x, y], {oppCol: oppCol, one: true}).length >= 1
+    );
   }
 
   // Stop at first king found (TODO: multi-kings)
@@ -1878,12 +1937,12 @@ export default class ChessRules {
         let square = kingPos,
             res = true; //a priori valid
         if (m.vanish.some(v => {
-          return (v.p == "k" || C.CannibalKings[v.p]) && v.c == color;
+          return C.CannibalKings[v.p] && v.c == color;
         })) {
           // Search king in appear array:
           const newKingIdx =
             m.appear.findIndex(a => {
-              return (a.p == "k" || C.CannibalKings[a.p]) && a.c == color;
+              return C.CannibalKings[a.p] && a.c == color;
             });
           if (newKingIdx >= 0)
             square = [m.appear[newKingIdx].x, m.appear[newKingIdx].y];
@@ -1914,13 +1973,17 @@ export default class ChessRules {
 
   // Apply a move on board
   playOnBoard(move) {
-    for (let psq of move.vanish) this.board[psq.x][psq.y] = "";
-    for (let psq of move.appear) this.board[psq.x][psq.y] = psq.c + psq.p;
+    for (let psq of move.vanish)
+      this.board[psq.x][psq.y] = "";
+    for (let psq of move.appear)
+      this.board[psq.x][psq.y] = psq.c + psq.p;
   }
   // Un-apply the played move
   undoOnBoard(move) {
-    for (let psq of move.appear) this.board[psq.x][psq.y] = "";
-    for (let psq of move.vanish) this.board[psq.x][psq.y] = psq.c + psq.p;
+    for (let psq of move.appear)
+      this.board[psq.x][psq.y] = "";
+    for (let psq of move.vanish)
+      this.board[psq.x][psq.y] = psq.c + psq.p;
   }
 
   updateCastleFlags(move) {
@@ -1948,31 +2011,26 @@ export default class ChessRules {
 
   prePlay(move) {
     if (
-      typeof move.start.x == "number" &&
-      (!this.options["teleport"] || this.subTurnTeleport == 1)
+      this.hasCastle &&
+      // If flags already off, no need to re-check:
+      Object.keys(this.castleFlags).some(c => {
+        return this.castleFlags[c].some(val => val < this.size.y)})
     ) {
-      // OK, not a drop move
-      if (
-        this.hasCastle &&
-        // If flags already off, no need to re-check:
-        Object.keys(this.castleFlags).some(c => {
-          return this.castleFlags[c].some(val => val < this.size.y)})
-      ) {
-        this.updateCastleFlags(move);
-      }
-      const initSquare = C.CoordsToSquare(move.start);
-      if (
-        this.options["crazyhouse"] &&
-        (!this.options["rifle"] || !move.capture)
-      ) {
+      this.updateCastleFlags(move);
+    }
+    if (this.options["crazyhouse"]) {
+      move.vanish.forEach(v => {
+        const square = C.CoordsToSquare({x: v.x, y: v.y});
+        if (this.ispawn[square])
+          delete this.ispawn[square];
+      });
+      if (move.appear.length > 0 && move.vanish.length > 0) {
+        // Assumption: something is moving
+        const initSquare = C.CoordsToSquare(move.start);
         const destSquare = C.CoordsToSquare(move.end);
-        if (this.ispawn[initSquare]) {
-          delete this.ispawn[initSquare];
-          this.ispawn[destSquare] = true;
-        }
-        else if (
-          move.vanish[0].p == "p" &&
-          move.appear[0].p != "p"
+        if (
+          this.ispawn[initSquare] ||
+          (move.vanish[0].p == "p" && move.appear[0].p != "p")
         ) {
           this.ispawn[destSquare] = true;
         }
@@ -1986,18 +2044,28 @@ export default class ChessRules {
       }
     }
     const minSize = Math.min(move.appear.length, move.vanish.length);
-    if (this.hasReserve && !move.pawnfall) {
+    if (
+      this.hasReserve &&
+      // Warning; atomic pawn removal isn't a capture
+      (!this.options["atomic"] || !this.rempawn || this.movesCount >= 1)
+    ) {
       const color = this.turn;
       for (let i=minSize; i<move.appear.length; i++) {
         // Something appears = dropped on board (some exceptions, Chakart...)
-        const piece = move.appear[i].p;
-        this.updateReserve(color, piece, this.reserve[color][piece] - 1);
+        if (move.appear[i].c == color) {
+          const piece = move.appear[i].p;
+          this.updateReserve(color, piece, this.reserve[color][piece] - 1);
+        }
       }
       for (let i=minSize; i<move.vanish.length; i++) {
         // Something vanish: add to reserve except if recycle & opponent
-        const piece = move.vanish[i].p;
-        if (this.options["crazyhouse"] || move.vanish[i].c == color)
+        if (
+          this.options["crazyhouse"] ||
+          (this.options["recycle"] && move.vanish[i].c == color)
+        ) {
+          const piece = move.vanish[i].p;
           this.updateReserve(color, piece, this.reserve[color][piece] + 1);
+        }
       }
     }
   }
@@ -2104,12 +2172,9 @@ export default class ChessRules {
     return (color == "w" ? "0-1" : "1-0");
   }
 
-  // NOTE: quite suboptimal for eg. Benedict (not a big deal I think)
   playVisual(move, r) {
     move.vanish.forEach(v => {
-      // 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].remove();
       this.g_pieces[v.x][v.y] = null;
     });
     let chessboard =
@@ -2119,12 +2184,14 @@ export default class ChessRules {
     const pieceWidth = this.getPieceWidth(r.width);
     move.appear.forEach(a => {
       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");
+      C.AddClass_es(this.g_pieces[a.x][a.y], this.pieces()[a.p]["class"]);
+      this.g_pieces[a.x][a.y].classList.add(C.GetColorClass(a.c));
       this.g_pieces[a.x][a.y].style.width = pieceWidth + "px";
       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)`;
+      // Translate coordinates to use chessboard as reference:
+      this.g_pieces[a.x][a.y].style.transform =
+        `translate(${ip - r.x}px,${jp - r.y}px)`;
       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]);
@@ -2153,39 +2220,50 @@ export default class ChessRules {
       callback();
       return;
     }
-    let movingPiece = this.getDomPiece(move.start.x, move.start.y);
-    const initTransform = movingPiece.style.transform;
-    let chessboard =
-      document.getElementById(this.containerId).querySelector(".chessboard");
-    const r = chessboard.getBoundingClientRect();
-    const [ix, iy] = this.getPixelPosition(move.start.x, move.start.y, r);
+    let initPiece = this.getDomPiece(move.start.x, move.start.y);
+    // NOTE: cloning generally not required, but light enough, and simpler
+    let movingPiece = initPiece.cloneNode();
+    initPiece.style.opacity = "0";
+    let container =
+      document.getElementById(this.containerId)
+    const r = container.querySelector(".chessboard").getBoundingClientRect();
+    if (typeof move.start.x == "string") {
+      // Need to bound width/height (was 100% for reserve pieces)
+      const pieceWidth = this.getPieceWidth(r.width);
+      movingPiece.style.width = pieceWidth + "px";
+      movingPiece.style.height = pieceWidth + "px";
+    }
     const maxDist = this.getMaxDistance(r.width);
-    // NOTE: move.drag could be generalized per-segment (usage?)
+    const pieces = this.pieces();
     if (move.drag) {
-      // Drag something else: require cloning
-      movingPiece = movingPiece.cloneNode();
-      const pieces = this.pieces();
       const startCode = this.getPiece(move.start.x, move.start.y);
-      movingPiece.classList.remove(pieces[startCode]["class"]);
-      movingPiece.classList.add(pieces[move.drag.p]["class"]);
+      C.RemoveClass_es(movingPiece, pieces[startCode]["class"]);
+      C.AddClass_es(movingPiece, pieces[move.drag.p]["class"]);
       const apparentColor = this.getColor(move.start.x, move.start.y);
       if (apparentColor != move.drag.c) {
         movingPiece.classList.remove(C.GetColorClass(apparentColor));
         movingPiece.classList.add(C.GetColorClass(move.drag.c));
       }
-      chessboard.appendChild(movingPiece);
     }
+    container.appendChild(movingPiece);
     const animateSegment = (index, cb) => {
+      // NOTE: move.drag could be generalized per-segment (usage?)
       const [i1, j1] = move.segments[index][0];
       const [i2, j2] = move.segments[index][1];
       const dep = this.getPixelPosition(i1, j1, r);
       const arr = this.getPixelPosition(i2, j2, r);
+      movingPiece.style.transitionDuration = "0s";
+      movingPiece.style.transform = `translate(${dep[0]}px, ${dep[1]}px)`;
       const distance =
         Math.sqrt((arr[0] - dep[0]) ** 2 + (arr[1] - dep[1]) ** 2);
       const duration = 0.2 + (distance / maxDist) * 0.3;
-      movingPiece.style.transform = `translate(${arr[0]}px, ${arr[1]}px)`;
-      movingPiece.style.transitionDuration = duration + "s";
-      setTimeout(cb, duration * 1000);
+      // TODO: unclear why we need this new delay below:
+      setTimeout(() => {
+        movingPiece.style.transitionDuration = duration + "s";
+        // movingPiece is child of container: no need to adjust coordinates
+        movingPiece.style.transform = `translate(${arr[0]}px, ${arr[1]}px)`;
+        setTimeout(cb, duration * 1000);
+      }, 50);
     };
     if (!move.segments) {
       move.segments = [
@@ -2197,12 +2275,8 @@ export default class ChessRules {
       if (index < move.segments.length)
         animateSegment(index++, animateSegmentCallback);
       else {
-        if (move.drag)
-          movingPiece.remove();
-        else {
-          movingPiece.style.transform = initTransform;
-          movingPiece.style.transitionDuration = "0s";
-        }
+        movingPiece.remove();
+        initPiece.style.opacity = "1";
         callback();
       }
     };