#include #include #include #include #include \"game.h\" #include \"aaball.h\" #define CHECKERS_CELL_SIZE 40 #define CHECKERS_NUM_PIECES 4 #define CHECKERS_BOARD_WID 8 #define CHECKERS_BOARD_HEIT 8 #define CHECKERS_WK 1 #define CHECKERS_WP 2 #define CHECKERS_BK 3 #define CHECKERS_BP 4 #define CHECKERS_ISKING(x) (x == 1 || x == 3) #define CHECKERS_ISPAWN(x) (x == 2 || x == 4) #define CHECKERS_ISWHITE(x) (x >= 1 && x <= 2) #define CHECKERS_ISBLACK(x) (x >= 3 && x <= 4) char checkers_colors[] = {200, 200, 200, 220,220,255}; int checkers_init_pos[] = { 0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 , 4 , 0 , 4 , 0 , 4 , 0 , 4 , 0 , 0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 , 2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 , 0 , 2 , 0 , 2 , 0 , 2 , 0 , 2 , 2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 , }; static int checkers_max_moves = 200; void checkers_init (); int checkers_getmove (Pos *, int, int, GtkboardEventType, Player, byte **, int **); ResultType checkers_who_won (Pos *, Player, char **); byte *checkers_movegen (Pos *); ResultType checkers_eval (Pos *, Player, float *); char ** checkers_get_pixmap (int idx, int color); void checkers_reset_uistate (); Game Checkers = { CHECKERS_CELL_SIZE, CHECKERS_BOARD_WID, CHECKERS_BOARD_HEIT, CHECKERS_NUM_PIECES, checkers_colors, checkers_init_pos, NULL, \"Checkers\", checkers_init}; void checkers_init () { game_getmove = checkers_getmove; game_movegen = checkers_movegen; game_who_won = checkers_who_won; game_eval = checkers_eval; game_get_pixmap = checkers_get_pixmap; game_reset_uistate = checkers_reset_uistate; game_file_label = FILERANK_LABEL_TYPE_ALPHA; game_rank_label = FILERANK_LABEL_TYPE_NUM | FILERANK_LABEL_DESC; game_allow_flip = TRUE; game_doc_about = \"Checkers\ \" \"Two player game\ \" \"Status: Partially implemented (currently unplayable)\ \" \"URL: \"GAME_DEFAULT_URL(\"checkers\"); } ResultType checkers_who_won (Pos *pos, Player player, char **commp) { static char comment[32]; char *who_str [2] = { \"white won\", \"black won\"}; int found_w = 0, found_b = 0; int i; for (i=0; iboard[i])) found_w = 1; else if (CHECKERS_ISBLACK (pos->board[i])) found_b = 1; if (!found_b) { strncpy (comment, who_str[0], 31); *commp = comment; return RESULT_WHITE; } if (!found_w) { strncpy (comment, who_str[1], 31); *commp = comment; return RESULT_BLACK; } return RESULT_NOTYET; } byte * checkers_movegen (Pos *pos) { int i, j, diffx, diffy; byte movbuf [256]; byte *movlist, *mp = movbuf; byte *board = pos->board; Player player = pos->player; for (i=0; iboard [j * board_wid + i]) { case CHECKERS_WK: sum += (5 - fabs ((i-3.5) * (j-3.5)) / 10); break; case CHECKERS_WP: sum += (1 + j / 10.0); break; case CHECKERS_BK: sum -= (5 - fabs ((i-3.5) * (j-3.5)) / 10); break; case CHECKERS_BP: sum -= (1 + (board_heit - 1 - j) / 10.0); break; } } *eval = sum; return RESULT_NOTYET; } static int oldx = -1, oldy = -1; void checkers_reset_uistate () { oldx = -1, oldy = -1; } int checkers_getmove (Pos *pos, int x, int y, Gtkboa.

1. #include
#include
#include
#include
#include "game.h"
#include "aaball.h"
#define CHECKERS_CELL_SIZE 40
#define CHECKERS_NUM_PIECES 4
#define CHECKERS_BOARD_WID 8
#define CHECKERS_BOARD_HEIT 8
#define CHECKERS_WK 1
#define CHECKERS_WP 2
#define CHECKERS_BK 3
#define CHECKERS_BP 4
#define CHECKERS_ISKING(x) (x == 1 || x == 3)
#define CHECKERS_ISPAWN(x) (x == 2 || x == 4)
#define CHECKERS_ISWHITE(x) (x >= 1 && x <= 2)
#define CHECKERS_ISBLACK(x) (x >= 3 && x <= 4)
char checkers_colors[] =
{200, 200, 200,
220,220,255};
int checkers_init_pos[] =
{
0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 ,
4 , 0 , 4 , 0 , 4 , 0 , 4 , 0 ,
0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 ,
0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 ,
0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 ,
2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 ,
0 , 2 , 0 , 2 , 0 , 2 , 0 , 2 ,
2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 ,
};
static int checkers_max_moves = 200;

2. void checkers_init ();
int checkers_getmove (Pos *, int, int, GtkboardEventType, Player, byte **, int **);
ResultType checkers_who_won (Pos *, Player, char **);
byte *checkers_movegen (Pos *);
ResultType checkers_eval (Pos *, Player, float *);
char ** checkers_get_pixmap (int idx, int color);
void checkers_reset_uistate ();
Game Checkers =
{ CHECKERS_CELL_SIZE, CHECKERS_BOARD_WID,
CHECKERS_BOARD_HEIT,
CHECKERS_NUM_PIECES,
checkers_colors, checkers_init_pos, NULL, "Checkers",
checkers_init};
void checkers_init ()
{
game_getmove = checkers_getmove;
game_movegen = checkers_movegen;
game_who_won = checkers_who_won;
game_eval = checkers_eval;
game_get_pixmap = checkers_get_pixmap;
game_reset_uistate = checkers_reset_uistate;
game_file_label = FILERANK_LABEL_TYPE_ALPHA;
game_rank_label = FILERANK_LABEL_TYPE_NUM | FILERANK_LABEL_DESC;
game_allow_flip = TRUE;
game_doc_about =
"Checkers "
"Two player game "
"Status: Partially implemented (currently unplayable) "
"URL: "GAME_DEFAULT_URL("checkers");
}
ResultType checkers_who_won (Pos *pos, Player player, char **commp)
{
static char comment[32];
char *who_str [2] = { "white won", "black won"};
int found_w = 0, found_b = 0;

3. int i;
for (i=0; iboard[i])) found_w = 1;
else if (CHECKERS_ISBLACK (pos->board[i])) found_b = 1;
if (!found_b)
{
strncpy (comment, who_str[0], 31);
*commp = comment;
return RESULT_WHITE;
}
if (!found_w)
{
strncpy (comment, who_str[1], 31);
*commp = comment;
return RESULT_BLACK;
}
return RESULT_NOTYET;
}
byte * checkers_movegen (Pos *pos)
{
int i, j, diffx, diffy;
byte movbuf [256];
byte *movlist, *mp = movbuf;
byte *board = pos->board;
Player player = pos->player;
for (i=0; iboard [j * board_wid + i])
{
case CHECKERS_WK: sum += (5 - fabs ((i-3.5) * (j-3.5)) / 10); break;
case CHECKERS_WP: sum += (1 + j / 10.0); break;
case CHECKERS_BK: sum -= (5 - fabs ((i-3.5) * (j-3.5)) / 10); break;
case CHECKERS_BP: sum -= (1 + (board_heit - 1 - j) / 10.0); break;
}
}
*eval = sum;
return RESULT_NOTYET;
}

4. static int oldx = -1, oldy = -1;
void checkers_reset_uistate ()
{
oldx = -1, oldy = -1;
}
int checkers_getmove (Pos *pos, int x, int y, GtkboardEventType type, Player to_play,
byte **movp, int ** rmovep)
{
static byte move[10];
byte *mp = move;
int diffx, diffy;
byte *board = pos->board;
if (type != GTKBOARD_BUTTON_RELEASE) return 0;
if (oldx < 0)
{
int val = board [y * board_wid + x];
if ((CHECKERS_ISWHITE(val) && !(to_play == WHITE)) ||
(CHECKERS_ISBLACK(val) && !(to_play == BLACK)))
return -1;
oldx = x; oldy = y;
return 0;
}
if (x == oldx && y == oldy)
{
oldx = -1; oldy = -1; return 0;
}
diffx = x - oldx;
if (abs (diffx) == 1)
{
diffy = y - oldy;
if (abs (diffy) != 1)

5. { oldx = oldy = -1; return -1;}
if (!CHECKERS_ISKING(board [oldy * board_wid + oldx])
&& diffy != (to_play == WHITE ? 1 : -1))
{ oldx = oldy = -1; return -1;}
if (board [y * board_wid + x] != 0)
{ oldx = oldy = -1; return -1;}
*mp++ = oldx; *mp++ = oldy; *mp++ = 0;
*mp++ = x; *mp++ = y;
if ((to_play == WHITE && y == board_heit - 1)
|| (to_play == BLACK && y == 0))
*mp++ = (to_play == WHITE ? CHECKERS_WK : CHECKERS_BK);
else
*mp++ = board [oldy * board_wid + oldx];
*mp++ = -1;
*movp = move;
oldx = oldy = -1;
return 1;
}
if (abs (diffx) == 2)
{
int val;
diffy = y - oldy;
if (abs (diffy) != 2)
{ oldx = oldy = -1; return -1;}
if (!CHECKERS_ISKING(board [oldy * board_wid + oldx])
&& diffy != (to_play == WHITE ? 2 : -2))
{ oldx = oldy = -1; return -1;}
if (board [y * board_wid + x] != 0)
{ oldx = oldy = -1; return -1;}
val = board [(y-diffy/2) * board_wid + (x-diffx/2)];
if ((!CHECKERS_ISWHITE(val) && (to_play == BLACK)) ||
(!CHECKERS_ISBLACK(val) && (to_play == WHITE)))
{ oldx = oldy = -1; return -1;}
*mp++ = oldx; *mp++ = oldy; *mp++ = 0;
*mp++ = oldx+diffx/2; *mp++ = oldy+diffy/2; *mp++ = 0;
*mp++ = x; *mp++ = y;

6. if ((to_play == WHITE && y == board_heit - 1)
|| (to_play == BLACK && y == 0))
*mp++ = (to_play == WHITE ? CHECKERS_WK : CHECKERS_BK);
else
*mp++ = board [oldy * board_wid + oldx];
*mp++ = -1;
*movp = move;
oldx = oldy = -1;
return 1;
}
{ oldx = oldy = -1; return -1;}
}
char ** checkers_get_pixmap (int idx, int color)
{
int bg;
int i;
static char pixbuf[CHECKERS_CELL_SIZE * (CHECKERS_CELL_SIZE+1)];
for(i=0, bg=0;i<3;i++)
{ int col = checkers_colors[i+3];
if (col<0) col += 256; bg += col * (1 << (16-8*i));}
return pixmap_ball_gen (CHECKERS_CELL_SIZE, pixbuf,
CHECKERS_ISWHITE(idx) ? 0xffffff : 0x0000ff, bg,
(idx == CHECKERS_WP || idx == CHECKERS_BP) ? 8 : 12, 24);
}
Solution
#include
#include
#include
#include
#include "game.h"
#include "aaball.h"
#define CHECKERS_CELL_SIZE 40
#define CHECKERS_NUM_PIECES 4

7. #define CHECKERS_BOARD_WID 8
#define CHECKERS_BOARD_HEIT 8
#define CHECKERS_WK 1
#define CHECKERS_WP 2
#define CHECKERS_BK 3
#define CHECKERS_BP 4
#define CHECKERS_ISKING(x) (x == 1 || x == 3)
#define CHECKERS_ISPAWN(x) (x == 2 || x == 4)
#define CHECKERS_ISWHITE(x) (x >= 1 && x <= 2)
#define CHECKERS_ISBLACK(x) (x >= 3 && x <= 4)
char checkers_colors[] =
{200, 200, 200,
220,220,255};
int checkers_init_pos[] =
{
0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 ,
4 , 0 , 4 , 0 , 4 , 0 , 4 , 0 ,
0 , 4 , 0 , 4 , 0 , 4 , 0 , 4 ,
0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 ,
0 , 0 , 0 , 0 , 0 , 0 , 0 , 0 ,
2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 ,
0 , 2 , 0 , 2 , 0 , 2 , 0 , 2 ,
2 , 0 , 2 , 0 , 2 , 0 , 2 , 0 ,
};
static int checkers_max_moves = 200;
void checkers_init ();
int checkers_getmove (Pos *, int, int, GtkboardEventType, Player, byte **, int **);
ResultType checkers_who_won (Pos *, Player, char **);
byte *checkers_movegen (Pos *);
ResultType checkers_eval (Pos *, Player, float *);
char ** checkers_get_pixmap (int idx, int color);
void checkers_reset_uistate ();
Game Checkers =
{ CHECKERS_CELL_SIZE, CHECKERS_BOARD_WID,

8. CHECKERS_BOARD_HEIT,
CHECKERS_NUM_PIECES,
checkers_colors, checkers_init_pos, NULL, "Checkers",
checkers_init};
void checkers_init ()
{
game_getmove = checkers_getmove;
game_movegen = checkers_movegen;
game_who_won = checkers_who_won;
game_eval = checkers_eval;
game_get_pixmap = checkers_get_pixmap;
game_reset_uistate = checkers_reset_uistate;
game_file_label = FILERANK_LABEL_TYPE_ALPHA;
game_rank_label = FILERANK_LABEL_TYPE_NUM | FILERANK_LABEL_DESC;
game_allow_flip = TRUE;
game_doc_about =
"Checkers "
"Two player game "
"Status: Partially implemented (currently unplayable) "
"URL: "GAME_DEFAULT_URL("checkers");
}
ResultType checkers_who_won (Pos *pos, Player player, char **commp)
{
static char comment[32];
char *who_str [2] = { "white won", "black won"};
int found_w = 0, found_b = 0;
int i;
for (i=0; iboard[i])) found_w = 1;
else if (CHECKERS_ISBLACK (pos->board[i])) found_b = 1;
if (!found_b)
{
strncpy (comment, who_str[0], 31);
*commp = comment;
return RESULT_WHITE;
}

9. if (!found_w)
{
strncpy (comment, who_str[1], 31);
*commp = comment;
return RESULT_BLACK;
}
return RESULT_NOTYET;
}
byte * checkers_movegen (Pos *pos)
{
int i, j, diffx, diffy;
byte movbuf [256];
byte *movlist, *mp = movbuf;
byte *board = pos->board;
Player player = pos->player;
for (i=0; iboard [j * board_wid + i])
{
case CHECKERS_WK: sum += (5 - fabs ((i-3.5) * (j-3.5)) / 10); break;
case CHECKERS_WP: sum += (1 + j / 10.0); break;
case CHECKERS_BK: sum -= (5 - fabs ((i-3.5) * (j-3.5)) / 10); break;
case CHECKERS_BP: sum -= (1 + (board_heit - 1 - j) / 10.0); break;
}
}
*eval = sum;
return RESULT_NOTYET;
}
static int oldx = -1, oldy = -1;
void checkers_reset_uistate ()
{
oldx = -1, oldy = -1;
}
int checkers_getmove (Pos *pos, int x, int y, GtkboardEventType type, Player to_play,

10. byte **movp, int ** rmovep)
{
static byte move[10];
byte *mp = move;
int diffx, diffy;
byte *board = pos->board;
if (type != GTKBOARD_BUTTON_RELEASE) return 0;
if (oldx < 0)
{
int val = board [y * board_wid + x];
if ((CHECKERS_ISWHITE(val) && !(to_play == WHITE)) ||
(CHECKERS_ISBLACK(val) && !(to_play == BLACK)))
return -1;
oldx = x; oldy = y;
return 0;
}
if (x == oldx && y == oldy)
{
oldx = -1; oldy = -1; return 0;
}
diffx = x - oldx;
if (abs (diffx) == 1)
{
diffy = y - oldy;
if (abs (diffy) != 1)
{ oldx = oldy = -1; return -1;}
if (!CHECKERS_ISKING(board [oldy * board_wid + oldx])
&& diffy != (to_play == WHITE ? 1 : -1))
{ oldx = oldy = -1; return -1;}
if (board [y * board_wid + x] != 0)
{ oldx = oldy = -1; return -1;}
*mp++ = oldx; *mp++ = oldy; *mp++ = 0;
*mp++ = x; *mp++ = y;
if ((to_play == WHITE && y == board_heit - 1)

11. || (to_play == BLACK && y == 0))
*mp++ = (to_play == WHITE ? CHECKERS_WK : CHECKERS_BK);
else
*mp++ = board [oldy * board_wid + oldx];
*mp++ = -1;
*movp = move;
oldx = oldy = -1;
return 1;
}
if (abs (diffx) == 2)
{
int val;
diffy = y - oldy;
if (abs (diffy) != 2)
{ oldx = oldy = -1; return -1;}
if (!CHECKERS_ISKING(board [oldy * board_wid + oldx])
&& diffy != (to_play == WHITE ? 2 : -2))
{ oldx = oldy = -1; return -1;}
if (board [y * board_wid + x] != 0)
{ oldx = oldy = -1; return -1;}
val = board [(y-diffy/2) * board_wid + (x-diffx/2)];
if ((!CHECKERS_ISWHITE(val) && (to_play == BLACK)) ||
(!CHECKERS_ISBLACK(val) && (to_play == WHITE)))
{ oldx = oldy = -1; return -1;}
*mp++ = oldx; *mp++ = oldy; *mp++ = 0;
*mp++ = oldx+diffx/2; *mp++ = oldy+diffy/2; *mp++ = 0;
*mp++ = x; *mp++ = y;
if ((to_play == WHITE && y == board_heit - 1)
|| (to_play == BLACK && y == 0))
*mp++ = (to_play == WHITE ? CHECKERS_WK : CHECKERS_BK);
else
*mp++ = board [oldy * board_wid + oldx];
*mp++ = -1;
*movp = move;
oldx = oldy = -1;
return 1;

12. }
{ oldx = oldy = -1; return -1;}
}
char ** checkers_get_pixmap (int idx, int color)
{
int bg;
int i;
static char pixbuf[CHECKERS_CELL_SIZE * (CHECKERS_CELL_SIZE+1)];
for(i=0, bg=0;i<3;i++)
{ int col = checkers_colors[i+3];
if (col<0) col += 256; bg += col * (1 << (16-8*i));}
return pixmap_ball_gen (CHECKERS_CELL_SIZE, pixbuf,
CHECKERS_ISWHITE(idx) ? 0xffffff : 0x0000ff, bg,
(idx == CHECKERS_WP || idx == CHECKERS_BP) ? 8 : 12, 24);
}