attack.c

#include "attack.h"

const int knDir[8] = { -8, -19,	-21, -12, 8, 19, 21, 12 };
const int rkDir[4] = {-1, -10, 1, 10};
const int biDir[4] = {-9, -11, 11, 9};
const int kiDir[8] = {-1, -10, 1, 10, -9, -11, 11, 9};

int sqAttacked(const int sq, const int side, const S_BOARD *pos) {

    int pce,index,t_sq,dir;

    ASSERT(sqOnBoard(sq));
    ASSERT(sideValid(side));
    ASSERT(checkBoard(pos));

    //pawns
    if(side == WHITE) {
        if(pos->pieces[sq-11] == wP || pos->pieces[sq-9] == wP) {
            return TRUE;
        }
    } else {
        if(pos->pieces[sq+11] == bP || pos->pieces[sq+9] == bP) {
            return TRUE;
        }
    }

    //knights
    for(index = 0; index < 8; index++) {
        pce = pos->pieces[sq+knDir[index]];
        if(pce != OFFBOARD && IsKn(pce) && pieceCol[pce] == side) {
            return TRUE;
        }
    }
    //rooks + queens
    for(index = 0; index < 4; index++) {
        dir = rkDir[index];
        t_sq = sq + dir;
        pce=pos->pieces[t_sq];
        while(pce != OFFBOARD) {
            if(pce != EMPTY) {
                if(IsRQ(pce) && pieceCol[pce] == side) {
                    return TRUE;
                }
                break;
            }
            t_sq += dir;
            pce=pos->pieces[t_sq];
        }
    }
    //bishops, queens
    for(index = 0; index < 4; index++) {
        dir = biDir[index];
        t_sq = sq + dir;
        pce = pos->pieces[t_sq];
        while(pce != OFFBOARD) {
            if(pce != EMPTY) {
                if(IsBQ(pce) && pieceCol[pce] == side) {
                    return TRUE;
                }
                break;
            }
            t_sq += dir;
            pce = pos->pieces[t_sq];
        }
    }
    // kings
    for(index = 0; index < 8; index++) {
        pce = pos->pieces[sq + kiDir[index]];
        if(pce != OFFBOARD && IsKi(pce) && pieceCol[pce]==side) {
            return TRUE;
        }
    }
    return FALSE;

}