1 /* $NetBSD: twinkle2.c,v 1.6 2005/05/23 04:04:49 christos Exp $ */ 2 3 /* 4 * 5 * Copyright (c) 1980, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)twinkle2.c 8.1 (Berkeley) 6/8/93 33 */ 34 35 #include <stdlib.h> 36 #include <unistd.h> 37 #include <curses.h> 38 #include <signal.h> 39 40 #define NCOLS 80 41 #define NLINES 24 42 #define MAXPATTERNS 4 43 44 typedef struct { 45 int y, x; 46 } LOCS; 47 48 static LOCS Layout[NCOLS * NLINES]; /* current board layout */ 49 50 static int Pattern, /* current pattern number */ 51 Numstars; /* number of stars in pattern */ 52 53 static void puton(char); 54 static void die(int); 55 static void makeboard(void); 56 static int ison(int, int); 57 58 static int AM; 59 static char *VS; 60 static char *TI; 61 static char *CL; 62 63 int 64 main(void) 65 { 66 char *sp; 67 char buf[1024]; 68 char *ptr = buf; 69 70 srand(getpid()); /* initialize random sequence */ 71 72 if (isatty(0)) { 73 initscr(); 74 gettmode(); 75 if ((sp = getenv("TERM")) != NULL) 76 setterm(sp); 77 signal(SIGINT, die); 78 } 79 else { 80 printf("Need a terminal on fd=%d\n", 0); 81 exit(1); 82 } 83 84 tgetent(buf, sp); 85 86 AM = tgetflag("am"); 87 TI = tgetstr("ti", &ptr); 88 if (TI == NULL) { 89 printf("terminal does not have the ti capability\n"); 90 exit(1); 91 } 92 VS = tgetstr("vs", &ptr); 93 if (VS == NULL) { 94 printf("terminal does not have the vs capability\n"); 95 exit(1); 96 } 97 CL = tgetstr("cl", &ptr); 98 if (CL == NULL) { 99 printf("terminal does not have the cl capability\n"); 100 exit(1); 101 } 102 puts(TI); 103 puts(VS); 104 105 noecho(); 106 nonl(); 107 tputs(CL, NLINES, putchar); 108 for (;;) { 109 makeboard(); /* make the board setup */ 110 puton('*'); /* put on '*'s */ 111 puton(' '); /* cover up with ' 's */ 112 } 113 } 114 115 /* 116 * On program exit, move the cursor to the lower left corner by 117 * direct addressing, since current location is not guaranteed. 118 * We lie and say we used to be at the upper right corner to guarantee 119 * absolute addressing. 120 */ 121 static void 122 die(int n) 123 { 124 signal(SIGINT, SIG_IGN); 125 mvcur(0, COLS - 1, LINES - 1, 0); 126 endwin(); 127 exit(n); 128 } 129 130 static void 131 puton(char ch) 132 { 133 LOCS *lp; 134 int r; 135 LOCS *end; 136 LOCS temp; 137 static int lasty, lastx; 138 139 end = &Layout[Numstars]; 140 for (lp = Layout; lp < end; lp++) { 141 r = rand() % Numstars; 142 temp = *lp; 143 *lp = Layout[r]; 144 Layout[r] = temp; 145 } 146 147 for (lp = Layout; lp < end; lp++) 148 /* prevent scrolling */ 149 if (!AM || (lp->y < NLINES - 1 || lp->x < NCOLS - 1)) { 150 mvcur(lasty, lastx, lp->y, lp->x); 151 putchar(ch); 152 lasty = lp->y; 153 if ((lastx = lp->x + 1) >= NCOLS) 154 if (AM) { 155 lastx = 0; 156 lasty++; 157 } 158 else 159 lastx = NCOLS - 1; 160 } 161 } 162 163 /* 164 * Make the current board setup. It picks a random pattern and 165 * calls ison() to determine if the character is on that pattern 166 * or not. 167 */ 168 static void 169 makeboard(void) 170 { 171 int y, x; 172 LOCS *lp; 173 174 Pattern = rand() % MAXPATTERNS; 175 lp = Layout; 176 for (y = 0; y < NLINES; y++) 177 for (x = 0; x < NCOLS; x++) 178 if (ison(y, x)) { 179 lp->y = y; 180 lp->x = x; 181 lp++; 182 } 183 Numstars = lp - Layout; 184 } 185 186 /* 187 * Return TRUE if (y, x) is on the current pattern. 188 */ 189 static int 190 ison(int y, int x) 191 { 192 switch (Pattern) { 193 case 0: /* alternating lines */ 194 return !(y & 01); 195 case 1: /* box */ 196 if (x >= LINES && y >= NCOLS) 197 return FALSE; 198 if (y < 3 || y >= NLINES - 3) 199 return TRUE; 200 return (x < 3 || x >= NCOLS - 3); 201 case 2: /* holy pattern! */ 202 return ((x + y) & 01); 203 case 3: /* bar across center */ 204 return (y >= 9 && y <= 15); 205 } 206 /* NOTREACHED */ 207 } 208
Indexes created Sat Sep 20 22:09:52 GMT 2025