Add validation for remaining pieces

This commit is contained in:
Ole Morud
2023-03-19 20:37:07 +01:00
parent 7a2f961c69
commit 37fc5e7838

178
chess.c
View File

@@ -25,47 +25,46 @@ typedef ssize_t pos_t;
#define N ( (tile_t) 5 ) /* knight */
#define P ( (tile_t) 6 ) /* pawn */
#define WHITE 1
#define BG_DARKBLUE() setcolor(0, 100, 100, 150)
#define BG_LIGHTBLUE() setcolor(0, 150, 150, 200)
#define FG_BLACK() setcolor(1, 0, 0, 0)
#define FG_WHITE() setcolor(1, 0xff, 0xff, 0xff)
#define WHITE 1
#define BLACK -1
#define UNICODE_CHESS_SYMBOL 0x2659
int get_piece(char* input);
void setcolor(int mode, int r, int g, int b);
void print_board(tile_t* board);
void init_board(tile_t* board);
void do_turn(int turn_no, tile_t *board);
bool move_ok(tile_t* board, pos_t from, pos_t to, int player);
bool tile_empty(tile_t t);
bool bishop_move_ok(tile_t const* board, pos_t from, pos_t to);
bool cardinal_move_ok(tile_t const *board, pos_t from, pos_t to);
bool diagonal_move_ok(tile_t const *board, pos_t from, pos_t to);
bool king_move_ok(tile_t const *board, pos_t from, pos_t to);
bool knight_move_ok(pos_t from, pos_t to);
bool move_ok(tile_t* board, pos_t from, pos_t to, int player);
bool pawn_move_ok(tile_t const* board, pos_t from, pos_t to, int direction);
bool queen_move_ok(tile_t const *board, pos_t from, pos_t to);
bool rook_move_ok(tile_t const *board, pos_t from, pos_t to);
bool tile_empty(tile_t t);
int get_piece(char* input);
pos_t abs_pos(pos_t p);
pos_t column(pos_t t);
pos_t row(pos_t t);
tile_t abs_tile(tile_t t);
void do_turn(int turn_no, tile_t *board);
void init_board(tile_t* board);
void print_board(tile_t* board);
void setcolor(int mode, int r, int g, int b);
bool pawn_move_ok(tile_t const *board, pos_t from, pos_t to, int direction);
bool bishop_move_ok(tile_t const* board, pos_t from, pos_t to);
/*
* main
*/
int main(){
int turn = 0;
setlocale(LC_ALL, "C.UTF-8");
tile_t *board = malloc(BOARD_SIZE);
tile_t board[8*8] = { 0 };
init_board(board);
while(1){
while(1) {
print_board(board);
do_turn(turn++, board);
}
@@ -313,11 +312,23 @@ bool move_ok(tile_t* board, pos_t from, pos_t to, int const player)
/* BISHOPS */
case B:
return bishop_move_ok(board, from, to);
/* ROOKS */
case R:
return rook_move_ok(board, from, to);
// the remaining pieces are left as an exercise for the reader
/* KNIGHTS */
case N:
return knight_move_ok(from, to);
case K:
return king_move_ok(board, from, to);
case Q:
return queen_move_ok(board, from, to);
}
return 0;
return false;
}
/* Returns true if move is a valid pawn move
@@ -346,6 +357,10 @@ bool pawn_move_ok(tile_t const* board, pos_t from, pos_t to, int direction)
}
}
/* Returns true if `to` is on a diagonal line of `from`
board - array of tiles representing chess board state
from - index of board piece is at
to - index of board piece tries to move to */
bool diagonal_move_ok(tile_t const *board, pos_t from, pos_t to)
{
pos_t const col_diff = column(to) - column(from);
@@ -354,32 +369,105 @@ bool diagonal_move_ok(tile_t const *board, pos_t from, pos_t to)
pos_t const x_step = col_diff / abs_pos(col_diff);
pos_t const y_step = ROW * row_diff / abs_pos(row_diff);
pos_t const step = x_step + y_step;
if ( abs_pos(col_diff) != abs_pos(row_diff) ) {
printf("\nnot a diagonal move");
return false;
}
for (pos_t p = from + step; p != to; p += step) {
if (!tile_empty(board[p]))
if (!tile_empty(board[p])) {
printf("\ncan't jump over pieces");
return false;
}
}
return true;
}
/* Returns true if `to` is in a cardinal line of `from`
board - array of tiles representing chess board state
from - index of board piece is at
to - index of board piece tries to move to */
bool cardinal_move_ok(tile_t const *board, pos_t from, pos_t to)
{
pos_t const col_diff = column(to) - column(from);
pos_t const row_diff = row(to) - row(from);
if (row_diff > 0 && col_diff > 0) {
printf("Must move in a straight line");
}
pos_t step;
if (row_diff) {
step = ROW * row_diff / abs_pos(row_diff);
} else {
step = col_diff / abs_pos(col_diff);
}
for (pos_t p = from + step; p != to; p += step) {
if (!tile_empty(board[p])) {
printf("\ncan't jump over pieces");
return false;
}
}
return true;
}
/* Returns true if move is a valid bishop move
board - array of tiles representing chess board state
from - index of board bishop is at
to - index of board bishop wants to move to */
board - array of tiles representing chess board state
from - index of board bishop is at
to - index of board bishop wants to move to */
bool bishop_move_ok(tile_t const* board, pos_t from, pos_t to)
{
pos_t const diff = to - from;
if ( diff % (ROW+COL) != 0 && diff % (ROW-COL) != 0 ) {
printf("bishops can only move diagonally");
return false;
}
if (!diagonal_move_ok(board, from, to)) {
printf("cant jump over pieces");
return false;
}
return true;
return diagonal_move_ok(board, from, to);
}
/* Returns true if move is a valid rook move
board - array of tiles representing chess board state
from - index of board rook is at
to - index of board rook wants to move to */
bool rook_move_ok(tile_t const *board, pos_t from, pos_t to)
{
return cardinal_move_ok(board, from, to);
}
/* Returns true if move is a valid knight move
board - array of tiles representing chess board state
from - index of board knight is at
to - index of board knight wants to move to */
bool knight_move_ok(pos_t from, pos_t to)
{
pos_t const abs_col_diff = abs_pos(column(to) - column(from));
pos_t const abs_row_diff = abs_pos(row(to) - row(from));
return (abs_col_diff == 1 && abs_row_diff == 2)
|| (abs_col_diff == 2 && abs_row_diff == 1);
}
/* Returns true if move is a valid king move
board - array of tiles representing chess board state
from - index of board king is at
to - index of board king wants to move to */
bool king_move_ok(tile_t const *board, pos_t from, pos_t to)
{
pos_t const abs_col_diff = abs_pos(column(to) - column(from));
pos_t const abs_row_diff = abs_pos(row(to) - row(from));
(void)board;
return abs_col_diff <= 1
&& abs_row_diff <= 1;
}
/* Returns true if move is a valid queen move
board - array of tiles representing chess board state
from - index of board queen is at
to - index of board queen wants to move to */
bool queen_move_ok(tile_t const *board, pos_t from, pos_t to)
{
return diagonal_move_ok(board, from, to)
|| cardinal_move_ok(board, from, to);
}