59 lines
1.2 KiB
C
59 lines
1.2 KiB
C
/* SCCS Id: @(#)track.c 3.5 87/08/08 */
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/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
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/* NetHack may be freely redistributed. See license for details. */
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/* track.c - version 1.0.2 */
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#include "hack.h"
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#define UTSZ 50
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STATIC_VAR NEARDATA int utcnt, utpnt;
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STATIC_VAR NEARDATA coord utrack[UTSZ];
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void
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initrack()
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{
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utcnt = utpnt = 0;
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}
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/* add to track */
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void
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settrack()
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{
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if(utcnt < UTSZ) utcnt++;
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if(utpnt == UTSZ) utpnt = 0;
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utrack[utpnt].x = u.ux;
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utrack[utpnt].y = u.uy;
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utpnt++;
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}
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coord *
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gettrack(x, y)
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register int x, y;
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{
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register int cnt, ndist;
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register coord *tc;
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cnt = utcnt;
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for(tc = &utrack[utpnt]; cnt--; ){
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if(tc == utrack) tc = &utrack[UTSZ-1];
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else tc--;
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ndist = distmin(x,y,tc->x,tc->y);
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/* if far away, skip track entries til we're closer */
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if(ndist > 2) {
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ndist -= 2; /* be careful due to extra decrement at top of loop */
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cnt -= ndist;
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if(cnt <= 0)
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return (coord *) 0; /* too far away, no matches possible */
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if(tc < &utrack[ndist])
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tc += (UTSZ-ndist);
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else
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tc -= ndist;
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} else if(ndist <= 1)
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return(ndist ? tc : 0);
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}
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return (coord *)0;
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}
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/*track.c*/
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