rockbox/apps/plugins/reversi/reversi-strategy-simple.c
Andrew Mahone 23d9812273 loader-initialized global plugin API:
struct plugin_api *rb is declared in PLUGIN_HEADER, and pointed to by
__header.api

the loader uses this pointer to initialize rb before calling entry_point

entry_point is no longer passed a pointer to the plugin API

all plugins, and pluginlib functions, are modified to refer to the
global rb

pluginlib functions which only served to copy the API pointer are
removed

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19776 a1c6a512-1295-4272-9138-f99709370657
2009-01-16 10:34:40 +00:00

119 lines
3.6 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (c) 2007 Antoine Cellerier
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "reversi-strategy.h"
/**
* Simple strategy:
* A very simple strategy. Makes the highest scoring move taking the other
* player's next best move into account.
* From Algorithm by Claudio Clemens in hinversi, simpleClient.c
*/
static void reversi_copy_board(reversi_board_t *dst,
const reversi_board_t *src) {
int i;
rb->memcpy(dst->history,src->history,
(BOARD_SIZE*BOARD_SIZE - INIT_STONES)*sizeof(move_t));
for(i=0;i<BOARD_SIZE;i++) {
rb->memcpy(dst->board[i],src->board[i],BOARD_SIZE*sizeof(int));
}
}
static int reversi_sim_move(const reversi_board_t *game, const int row,
const int col, const int player) {
reversi_board_t game_clone;
reversi_copy_board(&game_clone,game);
return reversi_make_move(&game_clone,row,col,player);
}
static int reversi_get_max_moves(const reversi_board_t *game, int player) {
int max = -BOARD_SIZE*BOARD_SIZE;
int row, col;
for(row=0; row<BOARD_SIZE; row++) {
for(col=0; col<BOARD_SIZE; col++) {
int v = reversi_sim_move(game,row,col,player);
if(v>max)
max = v;
}
}
return max;
}
static int reversi_sim_move2(const reversi_board_t *game, const int row,
const int col, const int player) {
/* Takes the other player's next best move into account */
int score;
reversi_board_t game_clone;
reversi_copy_board(&game_clone,game);
score = reversi_make_move(&game_clone,row,col,player);
return score - reversi_get_max_moves(&game_clone,
reversi_flipped_color(player));
}
static move_t simple_move_func(const reversi_board_t *game, int player) {
int max = -BOARD_SIZE*BOARD_SIZE;
int count = 0;
int row, col;
int r;
for(row=0; row<BOARD_SIZE; row++) {
for(col=0; col<BOARD_SIZE; col++) {
int v = reversi_sim_move2(game,row,col,player);
if(v>max) {
max = v;
count = 1;
}
else if(v==max) {
count ++;
}
}
}
if(!count) return MOVE_INVALID;
/* chose one of the moves which scores highest */
r = rb->rand()%count;
row = 0;
col = 0;
while(true) {
if(reversi_sim_move2(game, row, col, player)==max) {
r--;
if(r<0) {
return MAKE_MOVE(row,col,player);
}
}
col ++;
if(col==BOARD_SIZE) {
col = 0;
row ++;
if(row==BOARD_SIZE) {
row = 0;
}
}
}
}
const game_strategy_t strategy_simple = {
true,
NULL,
simple_move_func
};