CPW-Engine attacks

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This page holds the functions responsible for detecting if a given square is attacked by a given player.

isAttacked

#include "stdafx.h"
#include "0x88_math.h"

int isAttacked(char byColor, S8 sq) {
  /* pawns */
  if (byColor == WHITE) {
    if (IS_SQ(sq + SE) &&
      isPiece(WHITE, PAWN, sq + SE)
      )
      return 1;
    if (IS_SQ(sq + SW) &&
      isPiece(WHITE, PAWN, sq + SW)
      )
      return 1;
  }
  else {
    if (IS_SQ(sq + NE) &&
      isPiece(BLACK, PAWN, sq + NE)
      )
      return 1;
    if (IS_SQ(sq + NW) &&
      isPiece(BLACK, PAWN, sq + NW)
      )
      return 1;
  }

  /* knights */
  if (leaperAttack(byColor, sq, KNIGHT))
    return 1;

  /* kings */
  if (leaperAttack(byColor, sq, KING))
    return 1;

  /* straight line sliders */
  if (straightAttack(byColor, sq, NORTH) ||
    straightAttack(byColor, sq, SOUTH) ||
    straightAttack(byColor, sq, EAST) ||
    straightAttack(byColor, sq, WEST)
    )
    return 1;

  /* diagonal sliders */
  if (diagAttack(byColor, sq, NE) ||
    diagAttack(byColor, sq, SE) ||
    diagAttack(byColor, sq, NW) ||
    diagAttack(byColor, sq, SW)
    )
    return 1;

  return 0;
}

leaperAttack

int leaperAttack(char byColor, S8 sq, char byPiece) {
  S8 nextSq;
  for (int dir = 0; dir < 8; dir++) {
    nextSq = sq + vector[byPiece][dir];
    if (IS_SQ(nextSq) &&
      isPiece(byColor, byPiece, nextSq)
      )
      return 1;
  }
  return 0;
}

straightAttack

int straightAttack(char byColor, S8 sq, int vect) {
  int nextSq = sq + vect;

  while (IS_SQ(nextSq)) {
    if (b.color[nextSq] != COLOR_EMPTY) {
      if ((b.color[nextSq] == byColor) &&
        (b.pieces[nextSq] == ROOK || b.pieces[nextSq] == QUEEN)
        )
        return 1;
      return 0;
    }
    nextSq = nextSq + vect;
  }
  return 0;
}

diagAttack

int diagAttack(int byColor, S8 sq, int vect) {
  int nextSq = sq + vect;

  while (IS_SQ(nextSq)) {
    if (b.color[nextSq] != COLOR_EMPTY) {
      if ((b.color[nextSq] == byColor) &&
        (b.pieces[nextSq] == BISHOP || b.pieces[nextSq] == QUEEN)
        )
        return 1;
      return 0;
    }
    nextSq = nextSq + vect;
  }
  return 0;
}

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