tetris/shapes.c

   1 /*      $NetBSD: shapes.c,v 1.3 1997/10/12 02:03:47 lukem Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1992, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Chris Torek and Darren F. Provine.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)shapes.c    8.1 (Berkeley) 5/31/93
  39  */
  40
  41 /*
  42  * Tetris shapes and related routines.
  43  *
  44  * Note that the first 7 are `well known'.
  45  */
  46
  47 #include <sys/cdefs.h>
  48 #include "tetris.h"
  49
  50 #define TL      -B_COLS-1       /* top left */
  51 #define TC      -B_COLS         /* top center */
  52 #define TR      -B_COLS+1       /* top right */
  53 #define ML      -1              /* middle left */
  54 #define MR      1               /* middle right */
  55 #define BL      B_COLS-1        /* bottom left */
  56 #define BC      B_COLS          /* bottom center */
  57 #define BR      B_COLS+1        /* bottom right */
  58
  59 struct shape shapes[] = {
  60         /* 0*/  { 7,    { TL, TC, MR, } },
  61         /* 1*/  { 8,    { TC, TR, ML, } },
  62         /* 2*/  { 9,    { ML, MR, BC, } },
  63         /* 3*/  { 3,    { TL, TC, ML, } },
  64         /* 4*/  { 12,   { ML, BL, MR, } },
  65         /* 5*/  { 15,   { ML, BR, MR, } },
  66         /* 6*/  { 18,   { ML, MR, 2   } },      /* sticks out */
  67         /* 7*/  { 0,    { TC, ML, BL, } },
  68         /* 8*/  { 1,    { TC, MR, BR, } },
  69         /* 9*/  { 10,   { TC, MR, BC, } },
  70         /*10*/  { 11,   { TC, ML, MR, } },
  71         /*11*/  { 2,    { TC, ML, BC, } },
  72         /*12*/  { 13,   { TC, BC, BR, } },
  73         /*13*/  { 14,   { TR, ML, MR, } },
  74         /*14*/  { 4,    { TL, TC, BC, } },
  75         /*15*/  { 16,   { TR, TC, BC, } },
  76         /*16*/  { 17,   { TL, MR, ML, } },
  77         /*17*/  { 5,    { TC, BC, BL, } },
  78         /*18*/  { 6,    { TC, BC, 2*B_COLS } }  /* sticks out */
  79 };
  80
  81 /*
  82  * Return true iff the given shape fits in the given position,
  83  * taking the current board into account.
  84  */
  85 int
  86 fits_in(shape, pos)
  87         struct shape *shape;
  88         register int pos;
  89 {
  90         register int *o = shape->off;
  91
  92         if (board[pos] || board[pos + *o++] || board[pos + *o++] ||
  93             board[pos + *o])
  94                 return 0;
  95         return 1;
  96 }
  97
  98 /*
  99  * Write the given shape into the current board, turning it on
 100  * if `onoff' is 1, and off if `onoff' is 0.
 101  */
 102 void
 103 place(shape, pos, onoff)
 104         struct shape *shape;
 105         register int pos, onoff;
 106 {
 107         register int *o = shape->off;
 108
 109         board[pos] = onoff;
 110         board[pos + *o++] = onoff;
 111         board[pos + *o++] = onoff;
 112         board[pos + *o] = onoff;
 113 }