1 /*- 2 * Copyright (c) 1992 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Chris Torek and Darren F. Provine. 7 * 8 * %sccs.include.redist.c% 9 * 10 * @(#)shapes.c 5.2 (Berkeley) 12/23/92 11 */ 12 13 /* 14 * Tetris shapes and related routines. 15 * 16 * Note that the first 7 are `well known'. 17 */ 18 19 #include <sys/cdefs.h> 20 #include "tetris.h" 21 22 #define TL -B_COLS-1 /* top left */ 23 #define TC -B_COLS /* top center */ 24 #define TR -B_COLS+1 /* top right */ 25 #define ML -1 /* middle left */ 26 #define MR 1 /* middle right */ 27 #define BL B_COLS-1 /* bottom left */ 28 #define BC B_COLS /* bottom center */ 29 #define BR B_COLS+1 /* bottom right */ 30 31 struct shape shapes[] = { 32 /* 0*/ 7, TL, TC, MR, 33 /* 1*/ 8, TC, TR, ML, 34 /* 2*/ 9, ML, MR, BC, 35 /* 3*/ 3, TL, TC, ML, 36 /* 4*/ 12, ML, BL, MR, 37 /* 5*/ 15, ML, BR, MR, 38 /* 6*/ 18, ML, MR, /* sticks out */ 2, 39 /* 7*/ 0, TC, ML, BL, 40 /* 8*/ 1, TC, MR, BR, 41 /* 9*/ 10, TC, MR, BC, 42 /*10*/ 11, TC, ML, MR, 43 /*11*/ 2, TC, ML, BC, 44 /*12*/ 13, TC, BC, BR, 45 /*13*/ 14, TR, ML, MR, 46 /*14*/ 4, TL, TC, BC, 47 /*15*/ 16, TR, TC, BC, 48 /*16*/ 17, TL, MR, ML, 49 /*17*/ 5, TC, BC, BL, 50 /*18*/ 6, TC, BC, /* sticks out */ 2*B_COLS, 51 }; 52 53 /* 54 * Return true iff the given shape fits in the given position, 55 * taking the current board into account. 56 */ 57 int 58 fits_in(shape, pos) 59 struct shape *shape; 60 register int pos; 61 { 62 register int *o = shape->off; 63 64 if (board[pos] || board[pos + *o++] || board[pos + *o++] || 65 board[pos + *o]) 66 return 0; 67 return 1; 68 } 69 70 /* 71 * Write the given shape into the current board, turning it on 72 * if `onoff' is 1, and off if `onoff' is 0. 73 */ 74 void 75 place(shape, pos, onoff) 76 struct shape *shape; 77 register int pos, onoff; 78 { 79 register int *o = shape->off; 80 81 board[pos] = onoff; 82 board[pos + *o++] = onoff; 83 board[pos + *o++] = onoff; 84 board[pos + *o] = onoff; 85 } 86