xref: /netbsd-src/games/tetris/tetris.h (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: tetris.h,v 1.8 2000/01/01 10:15:17 jsm 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  *	@(#)tetris.h	8.1 (Berkeley) 5/31/93
39  */
40 
41 #include <sys/types.h>
42 
43 /*
44  * Definitions for Tetris.
45  */
46 
47 /*
48  * The display (`board') is composed of 23 rows of 12 columns of characters
49  * (numbered 0..22 and 0..11), stored in a single array for convenience.
50  * Columns 1 to 10 of rows 1 to 20 are the actual playing area, where
51  * shapes appear.  Columns 0 and 11 are always occupied, as are all
52  * columns of rows 21 and 22.  Rows 0 and 22 exist as boundary areas
53  * so that regions `outside' the visible area can be examined without
54  * worrying about addressing problems.
55  */
56 
57 	/* the board */
58 #define	B_COLS	12
59 #define	B_ROWS	23
60 #define	B_SIZE	(B_ROWS * B_COLS)
61 
62 typedef unsigned char cell;
63 extern cell	board[B_SIZE];	/* 1 => occupied, 0 => empty */
64 
65 	/* the displayed area (rows) */
66 #define	D_FIRST	1
67 #define	D_LAST	22
68 
69 	/* the active area (rows) */
70 #define	A_FIRST	1
71 #define	A_LAST	21
72 
73 /*
74  * Minimum display size.
75  */
76 #define	MINROWS	23
77 #define	MINCOLS	40
78 
79 extern int	Rows, Cols;	/* current screen size */
80 
81 /*
82  * Translations from board coordinates to display coordinates.
83  * As with board coordinates, display coordiates are zero origin.
84  */
85 #define	RTOD(x)	((x) - 1)
86 #define	CTOD(x)	((x) * 2 + (((Cols - 2 * B_COLS) >> 1) - 1))
87 
88 /*
89  * A `shape' is the fundamental thing that makes up the game.  There
90  * are 7 basic shapes, each consisting of four `blots':
91  *
92  *	X.X	  X.X		X.X
93  *	  X.X	X.X	X.X.X	X.X	X.X.X	X.X.X	X.X.X.X
94  *			  X		X	    X
95  *
96  *	  0	  1	  2	  3	  4	  5	  6
97  *
98  * Except for 3 and 6, the center of each shape is one of the blots.
99  * This blot is designated (0,0).  The other three blots can then be
100  * described as offsets from the center.  Shape 3 is the same under
101  * rotation, so its center is effectively irrelevant; it has been chosen
102  * so that it `sticks out' upward and leftward.  Except for shape 6,
103  * all the blots are contained in a box going from (-1,-1) to (+1,+1);
104  * shape 6's center `wobbles' as it rotates, so that while it `sticks out'
105  * rightward, its rotation---a vertical line---`sticks out' downward.
106  * The containment box has to include the offset (2,0), making the overall
107  * containment box range from offset (-1,-1) to (+2,+1).  (This is why
108  * there is only one row above, but two rows below, the display area.)
109  *
110  * The game works by choosing one of these shapes at random and putting
111  * its center at the middle of the first display row (row 1, column 5).
112  * The shape is moved steadily downward until it collides with something:
113  * either  another shape, or the bottom of the board.  When the shape can
114  * no longer be moved downwards, it is merged into the current board.
115  * At this time, any completely filled rows are elided, and blots above
116  * these rows move down to make more room.  A new random shape is again
117  * introduced at the top of the board, and the whole process repeats.
118  * The game ends when the new shape will not fit at (1,5).
119  *
120  * While the shapes are falling, the user can rotate them counterclockwise
121  * 90 degrees (in addition to moving them left or right), provided that the
122  * rotation puts the blots in empty spaces.  The table of shapes is set up
123  * so that each shape contains the index of the new shape obtained by
124  * rotating the current shape.  Due to symmetry, each shape has exactly
125  * 1, 2, or 4 rotations total; the first 7 entries in the table represent
126  * the primary shapes, and the remaining 12 represent their various
127  * rotated forms.
128  */
129 struct shape {
130 	int	rot;	/* index of rotated version of this shape */
131 	int	off[3];	/* offsets to other blots if center is at (0,0) */
132 };
133 
134 extern const struct shape shapes[];
135 #define	randshape() (&shapes[random() % 7])
136 
137 extern const struct shape *curshape;
138 extern const struct shape *nextshape;
139 
140 /*
141  * Shapes fall at a rate faster than once per second.
142  *
143  * The initial rate is determined by dividing 1 million microseconds
144  * by the game `level'.  (This is at most 1 million, or one second.)
145  * Each time the fall-rate is used, it is decreased a little bit,
146  * depending on its current value, via the `faster' macro below.
147  * The value eventually reaches a limit, and things stop going faster,
148  * but by then the game is utterly impossible.
149  */
150 extern long	fallrate;	/* less than 1 million; smaller => faster */
151 #define	faster() (fallrate -= fallrate / 3000)
152 
153 /*
154  * Game level must be between 1 and 9.  This controls the initial fall rate
155  * and affects scoring.
156  */
157 #define	MINLEVEL	1
158 #define	MAXLEVEL	9
159 
160 /*
161  * Scoring is as follows:
162  *
163  * When the shape comes to rest, and is integrated into the board,
164  * we score one point.  If the shape is high up (at a low-numbered row),
165  * and the user hits the space bar, the shape plummets all the way down,
166  * and we score a point for each row it falls (plus one more as soon as
167  * we find that it is at rest and integrate it---until then, it can
168  * still be moved or rotated).
169  */
170 extern int	score;		/* the obvious thing */
171 extern gid_t	gid, egid;
172 
173 extern char	key_msg[100];
174 extern int	showpreview;
175 
176 int	fits_in __P((const struct shape *, int));
177 void	place __P((const struct shape *, int, int));
178 void	stop __P((const char *)) __attribute__((__noreturn__));
179