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36 static char sccsid[] = "@(#)compkl.c 8.1 (Berkeley) 5/31/93";
38 static const char rcsid[] =
45 ** compute klingon distances
47 ** The klingon list has the distances for all klingons recomputed
48 ** and sorted. The parameter is a Boolean flag which is set if
49 ** we have just entered a new quadrant.
51 ** This routine is used every time the Enterprise or the Klingons
56 int f; /* set if new quadrant */
64 for (i = 0; i < Etc.nkling; i++)
66 /* compute distance to the Klingon */
67 dx = Ship.sectx - Etc.klingon[i].x;
68 dy = Ship.secty - Etc.klingon[i].y;
69 d = dx * dx + dy * dy;
72 /* compute average of new and old distances to Klingon */
75 temp = Etc.klingon[i].dist;
76 Etc.klingon[i].avgdist = 0.5 * (temp + d);
80 /* new quadrant: average is current */
81 Etc.klingon[i].avgdist = d;
83 Etc.klingon[i].dist = d;
86 /* leave them sorted */
94 ** bubble sort on ascending distance
107 for (i = 0; i < m; i++)
108 if (Etc.klingon[i].dist > Etc.klingon[i+1].dist)
110 bmove(&Etc.klingon[i], &t, sizeof t);
111 bmove(&Etc.klingon[i+1], &Etc.klingon[i], sizeof t);
112 bmove(&t, &Etc.klingon[i+1], sizeof t);