add Nuclear (#703)

src/parser.cpp

@@ -360,6 +360,7 @@ Variant* VariantParser<DoCheck>::parse(Variant* v) {
     parse_attribute("blastImmuneTypes", v->blastImmuneTypes, v->pieceToChar);
     parse_attribute("mutuallyImmuneTypes", v->mutuallyImmuneTypes, v->pieceToChar);
     parse_attribute("petrifyOnCapture", v->petrifyOnCapture);
+    parse_attribute("petrifyBlastPieces", v->petrifyBlastPieces);
     parse_attribute("doubleStep", v->doubleStep);
     parse_attribute("doubleStepRegionWhite", v->doubleStepRegion[WHITE]);
     parse_attribute("doubleStepRegionBlack", v->doubleStepRegion[BLACK]);

src/position.cpp

@@ -2003,7 +2003,7 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
           }
 
           // Make a wall square where the piece was
-          if (var->petrifyOnCapture)
+          if (bsq == to ? var->petrifyOnCapture : var->petrifyBlastPieces)
           {
               st->wallSquares |= bsq;
               byTypeBB[ALL_PIECES] |= bsq;

src/variant.h

@@ -67,6 +67,7 @@ struct Variant {
   PieceSet blastImmuneTypes = NO_PIECE_SET;
   PieceSet mutuallyImmuneTypes = NO_PIECE_SET;
   bool petrifyOnCapture = false;
+  bool petrifyBlastPieces = false;
   bool doubleStep = true;
   Bitboard doubleStepRegion[COLOR_NB] = {Rank2BB, Rank7BB};
   Bitboard tripleStepRegion[COLOR_NB] = {};

src/variants.ini

@@ -169,6 +169,7 @@
 # blastImmuneTypes: pieces completely immune to explosions (even at ground zero) [PieceSet] (default: none)
 # mutuallyImmuneTypes: pieces that can't capture another piece of same types (e.g., kings (commoners) in atomar) [PieceSet] (default: none)
 # petrifyOnCapture: non-pawn pieces are turned into wall squares when capturing [bool] (default: false)
+# petrifyBlastPieces: if petrify and blast combined, should pieces destroyed in the blast be petrified? [bool] (default: false)
 # doubleStep: enable pawn double step [bool] (default: true)
 # doubleStepRegionWhite: region where pawn double steps are allowed for white [Bitboard] (default: *2)
 # doubleStepRegionBlack: region where pawn double steps are allowed for black [Bitboard] (default: *2)
@@ -1334,7 +1335,7 @@ customPiece1 = i:NN
 customPiece2 = h:mfWcfFfhmnN
 startFen = r8r/3nkqn3/hcb1ii1bch/1hhhhhhhh1/10/10/1HHHHHHHH1/HCB1II1BCH/3NKQN3/R8R
 #technically not needed because of initial setup
-##enPassantRegion = 0
+##enPassantRegion = -
 ##castling = false
 
 #https://boardgamegeek.com/boardgame/32/buffalo-chess
@@ -1582,3 +1583,14 @@ customPiece4 = w:mRpRFAcpR
 customPiece5 = f:mBpBWDcpB
 promotedPieceType = u:w a:w c:f i:f
 startFen = lnsgkgsnl/1rci1uab1/p1p1p1p1p/9/9/9/P1P1P1P1P/1BAU1ICR1/LNSGKGSNL[-] w 0 1
+
+#https://www.chessvariants.com/difftaking.dir/deadsquare.html
+[nuclear:atomic]
+#define a piece that looks exactly like a pawn, but is not one. Takes care of major differences:
+#1. Pawns can be petrified.
+#2. Pawns can be destroyed by explosions.
+pawn = -
+customPiece1 = p:fmWfceFifmnD
+pawnTypes = p
+petrifyOnCapture = true
+enPassantRegion = -