1 1.2 mycroft /* 2 1.2 mycroft * Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. 3 1.2 mycroft */ 4 1.2 mycroft 5 1.2 mycroft #ifndef lint 6 1.2 mycroft static char rcsid[] = "$Id: hack.track.c,v 1.2 1993/08/02 17:19:31 mycroft Exp $"; 7 1.2 mycroft #endif /* not lint */ 8 1.1 cgd 9 1.1 cgd #include "hack.h" 10 1.1 cgd 11 1.1 cgd #define UTSZ 50 12 1.1 cgd 13 1.1 cgd coord utrack[UTSZ]; 14 1.1 cgd int utcnt = 0; 15 1.1 cgd int utpnt = 0; 16 1.1 cgd 17 1.1 cgd initrack(){ 18 1.1 cgd utcnt = utpnt = 0; 19 1.1 cgd } 20 1.1 cgd 21 1.1 cgd /* add to track */ 22 1.1 cgd settrack(){ 23 1.1 cgd if(utcnt < UTSZ) utcnt++; 24 1.1 cgd if(utpnt == UTSZ) utpnt = 0; 25 1.1 cgd utrack[utpnt].x = u.ux; 26 1.1 cgd utrack[utpnt].y = u.uy; 27 1.1 cgd utpnt++; 28 1.1 cgd } 29 1.1 cgd 30 1.1 cgd coord * 31 1.1 cgd gettrack(x,y) register x,y; { 32 1.1 cgd register int i,cnt,dist; 33 1.1 cgd coord tc; 34 1.1 cgd cnt = utcnt; 35 1.1 cgd for(i = utpnt-1; cnt--; i--){ 36 1.1 cgd if(i == -1) i = UTSZ-1; 37 1.1 cgd tc = utrack[i]; 38 1.1 cgd dist = (x-tc.x)*(x-tc.x) + (y-tc.y)*(y-tc.y); 39 1.1 cgd if(dist < 3) 40 1.1 cgd return(dist ? &(utrack[i]) : 0); 41 1.1 cgd } 42 1.1 cgd return(0); 43 1.1 cgd } 44