1 /* $NetBSD: hack.track.c,v 1.8 2009/08/12 07:28:41 dholland Exp $ */ 2 3 /* 4 * Copyright (c) 1985, Stichting Centrum voor Wiskunde en Informatica, 5 * Amsterdam 6 * 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 are 10 * met: 11 * 12 * - Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * - 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 * 19 * - Neither the name of the Stichting Centrum voor Wiskunde en 20 * Informatica, nor the names of its contributors may be used to endorse or 21 * promote products derived from this software without specific prior 22 * written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 25 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 27 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 28 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 29 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 30 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 31 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 /* 38 * Copyright (c) 1982 Jay Fenlason <hack@gnu.org> 39 * All rights reserved. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. The name of the author may not be used to endorse or promote products 50 * derived from this software without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 53 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 54 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 55 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 56 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 57 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 58 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 59 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 60 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 61 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 62 */ 63 64 #include "hack.h" 65 #include "extern.h" 66 67 #define UTSZ 50 68 69 static coord utrack[UTSZ]; 70 static int utcnt = 0; 71 static int utpnt = 0; 72 73 void 74 initrack(void) 75 { 76 utcnt = utpnt = 0; 77 } 78 79 /* add to track */ 80 void 81 settrack(void) 82 { 83 if (utcnt < UTSZ) 84 utcnt++; 85 if (utpnt == UTSZ) 86 utpnt = 0; 87 utrack[utpnt].x = u.ux; 88 utrack[utpnt].y = u.uy; 89 utpnt++; 90 } 91 92 coord * 93 gettrack(int x, int y) 94 { 95 int i, cnt, distsq; 96 coord tc; 97 98 cnt = utcnt; 99 for (i = utpnt - 1; cnt--; i--) { 100 if (i == -1) 101 i = UTSZ - 1; 102 tc = utrack[i]; 103 distsq = (x - tc.x) * (x - tc.x) + (y - tc.y) * (y - tc.y); 104 if (distsq < 3) 105 return (distsq ? &(utrack[i]) : 0); 106 } 107 return (0); 108 } 109