97d6fade74
I'll push a formatting guide at some point. There may still be outstanding changes, but please feel free to resolve those as you arrive a them. To the best of my knowledge, there is no changes to the actual code content, but the formatter does have the occasional bug. If you run into an issue, please fix it!
154 lines
3.2 KiB
C
154 lines
3.2 KiB
C
/* NetHack 3.6 rnd.c $NHDT-Date: 1431192762 2015/05/09 17:32:42 $ $NHDT-Branch: master $:$NHDT-Revision: 1.14 $ */
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/* NetHack 3.6 rnd.c $Date: 2009/05/06 10:47:41 $ $Revision: 1.7 $ */
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/* SCCS Id: @(#)rnd.c 3.5 2004/08/27 */
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/* NetHack may be freely redistributed. See license for details. */
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#include "hack.h"
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/* "Rand()"s definition is determined by [OS]conf.h */
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#if defined(LINT) && defined(UNIX) /* rand() is long... */
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extern int NDECL(rand);
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#define RND(x) (rand() % x)
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#else /* LINT */
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#if defined(UNIX) || defined(RANDOM)
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#define RND(x) (int)(Rand() % (long) (x))
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#else
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/* Good luck: the bottom order bits are cyclic. */
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#define RND(x) (int)((Rand() >> 3) % (x))
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#endif
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#endif /* LINT */
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int rn2(x) /* 0 <= rn2(x) < x */
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register int x;
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{
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#ifdef BETA
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if (x <= 0) {
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debugpline1("rn2(%d) attempted", x);
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return (0);
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}
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x = RND(x);
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return (x);
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#else
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return (RND(x));
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#endif
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}
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int rnl(x) /* 0 <= rnl(x) < x; sometimes subtracting Luck */
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register int x; /* good luck approaches 0, bad luck approaches (x-1) */
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{
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register int i, adjustment;
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#ifdef BETA
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if (x <= 0) {
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debugpline1("rnl(%d) attempted", x);
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return (0);
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}
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#endif
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adjustment = Luck;
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if (x <= 15) {
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/* for small ranges, use Luck/3 (rounded away from 0);
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also guard against architecture-specific differences
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of integer division involving negative values */
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adjustment = (abs(adjustment) + 1) / 3 * sgn(adjustment);
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/*
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* 11..13 -> 4
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* 8..10 -> 3
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* 5.. 7 -> 2
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* 2.. 4 -> 1
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* -1,0,1 -> 0 (no adjustment)
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* -4..-2 -> -1
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* -7..-5 -> -2
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* -10..-8 -> -3
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* -13..-11-> -4
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*/
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}
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i = RND(x);
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if (adjustment && rn2(37 + abs(adjustment))) {
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i -= adjustment;
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if (i < 0)
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i = 0;
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else if (i >= x)
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i = x - 1;
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}
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return i;
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}
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int rnd(x) /* 1 <= rnd(x) <= x */
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register int x;
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{
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#ifdef BETA
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if (x <= 0) {
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debugpline1("rnd(%d) attempted", x);
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return (1);
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}
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x = RND(x) + 1;
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return (x);
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#else
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return (RND(x) + 1);
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#endif
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}
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int d(n, x) /* n <= d(n,x) <= (n*x) */
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register int n, x;
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{
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register int tmp = n;
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#ifdef BETA
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if (x < 0 || n < 0 || (x == 0 && n != 0)) {
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debugpline2("d(%d,%d) attempted", n, x);
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return (1);
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}
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#endif
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while (n--)
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tmp += RND(x);
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return (tmp); /* Alea iacta est. -- J.C. */
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}
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int
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rne(x)
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register int x;
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{
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register int tmp, utmp;
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utmp = (u.ulevel < 15) ? 5 : u.ulevel / 3;
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tmp = 1;
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while (tmp < utmp && !rn2(x))
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tmp++;
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return tmp;
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/* was:
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* tmp = 1;
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* while(!rn2(x)) tmp++;
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* return(min(tmp,(u.ulevel < 15) ? 5 : u.ulevel/3));
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* which is clearer but less efficient and stands a vanishingly
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* small chance of overflowing tmp
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*/
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}
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int
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rnz(i)
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int i;
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{
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#ifdef LINT
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int x = i;
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int tmp = 1000;
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#else
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register long x = i;
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register long tmp = 1000;
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#endif
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tmp += rn2(1000);
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tmp *= rne(4);
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if (rn2(2)) {
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x *= tmp;
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x /= 1000;
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} else {
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x *= 1000;
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x /= tmp;
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}
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return ((int) x);
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}
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/*rnd.c*/
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