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+/* -*- Mode: C; tab-width: 4 -*- */
+/* hop --- real plane fractals */
+
+#if 0
+static const char sccsid[] = "@(#)hop.c 5.00 2000/11/01 xlockmore";
+#endif
+
+/*-
+ * Copyright (c) 1991 by Patrick J. Naughton.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose and without fee is hereby granted,
+ * provided that the above copyright notice appear in all copies and that
+ * both that copyright notice and this permission notice appear in
+ * supporting documentation.
+ *
+ * This file is provided AS IS with no warranties of any kind. The author
+ * shall have no liability with respect to the infringement of copyrights,
+ * trade secrets or any patents by this file or any part thereof. In no
+ * event will the author be liable for any lost revenue or profits or
+ * other special, indirect and consequential damages.
+ *
+ * Revision History:
+ * Changes in xlockmore distribution
+ * 01-Nov-2000: Allocation checks
+ * 24-Jun-1997: EJK and RR functions stolen from xmartin2.2
+ * Ed Kubaitis <ejk@ux2.cso.uiuc.edu> ejk functions and xmartin
+ * Renaldo Recuerdo rr function, generalized exponent version
+ * of the Barry Martin's square root function
+ * 10-May-1997: Compatible with xscreensaver
+ * 27-Jul-1995: added Peter de Jong's hop from Scientific American
+ * July 87 p. 111. Sometimes they are amazing but there are a
+ * few duds (I did not see a pattern in the parameters).
+ * 29-Mar-1995: changed name from hopalong to hop
+ * 09-Dec-1994: added Barry Martin's sine hop
+ * Changes in original xlock
+ * 29-Oct-1990: fix bad (int) cast.
+ * 29-Jul-1990: support for multiple screens.
+ * 08-Jul-1990: new timing and colors and new algorithm for fractals.
+ * 15-Dec-1989: Fix for proper skipping of {White,Black}Pixel() in colors.
+ * 08-Oct-1989: Fixed long standing typo bug in RandomInitHop();
+ * Fixed bug in memory allocation in init_hop();
+ * Moved seconds() to an extern.
+ * Got rid of the % mod since .mod is slow on a sparc.
+ * 20-Sep-1989: Lint.
+ * 31-Aug-1988: Forked from xlock.c for modularity.
+ * 23-Mar-1988: Coded HOPALONG routines from Scientific American Sept. 86 p. 14.
+ * Hopalong was attributed to Barry Martin of Aston University
+ * (Birmingham, England)
+ */
+
+
+#ifdef STANDALONE
+#define MODE_hop
+#define DEFAULTS "*delay: 10000 \n" \
+ "*count: 1000 \n" \
+ "*cycles: 2500 \n" \
+ "*ncolors: 200 \n" \
+ "*fpsSolid: true \n" \
+ "*ignoreRotation: True \n" \
+
+# define SMOOTH_COLORS
+# define reshape_hop 0
+# define release_hop 0
+# define hop_handle_event 0
+# include "xlockmore.h" /* in xscreensaver distribution */
+#else /* STANDALONE */
+# include "xlock.h" /* in xlockmore distribution */
+#endif /* STANDALONE */
+
+#ifdef MODE_hop
+
+#define DEF_MARTIN "False"
+#define DEF_POPCORN "False"
+#define DEF_EJK1 "False"
+#define DEF_EJK2 "False"
+#define DEF_EJK3 "False"
+#define DEF_EJK4 "False"
+#define DEF_EJK5 "False"
+#define DEF_EJK6 "False"
+#define DEF_RR "False"
+#define DEF_JONG "False"
+#define DEF_SINE "False"
+
+static Bool martin;
+static Bool popcorn;
+static Bool ejk1;
+static Bool ejk2;
+static Bool ejk3;
+static Bool ejk4;
+static Bool ejk5;
+static Bool ejk6;
+static Bool rr;
+static Bool jong;
+static Bool sine;
+
+static XrmOptionDescRec opts[] =
+{
+ {"-martin", ".hop.martin", XrmoptionNoArg, "on"},
+ {"+martin", ".hop.martin", XrmoptionNoArg, "off"},
+ {"-popcorn", ".hop.popcorn", XrmoptionNoArg, "on"},
+ {"+popcorn", ".hop.popcorn", XrmoptionNoArg, "off"},
+ {"-ejk1", ".hop.ejk1", XrmoptionNoArg, "on"},
+ {"+ejk1", ".hop.ejk1", XrmoptionNoArg, "off"},
+ {"-ejk2", ".hop.ejk2", XrmoptionNoArg, "on"},
+ {"+ejk2", ".hop.ejk2", XrmoptionNoArg, "off"},
+ {"-ejk3", ".hop.ejk3", XrmoptionNoArg, "on"},
+ {"+ejk3", ".hop.ejk3", XrmoptionNoArg, "off"},
+ {"-ejk4", ".hop.ejk4", XrmoptionNoArg, "on"},
+ {"+ejk4", ".hop.ejk4", XrmoptionNoArg, "off"},
+ {"-ejk5", ".hop.ejk5", XrmoptionNoArg, "on"},
+ {"+ejk5", ".hop.ejk5", XrmoptionNoArg, "off"},
+ {"-ejk6", ".hop.ejk6", XrmoptionNoArg, "on"},
+ {"+ejk6", ".hop.ejk6", XrmoptionNoArg, "off"},
+ {"-rr", ".hop.rr", XrmoptionNoArg, "on"},
+ {"+rr", ".hop.rr", XrmoptionNoArg, "off"},
+ {"-jong", ".hop.jong", XrmoptionNoArg, "on"},
+ {"+jong", ".hop.jong", XrmoptionNoArg, "off"},
+ {"-sine", ".hop.sine", XrmoptionNoArg, "on"},
+ {"+sine", ".hop.sine", XrmoptionNoArg, "off"}
+};
+static argtype vars[] =
+{
+ {&martin, "martin", "Martin", DEF_MARTIN, t_Bool},
+ {&popcorn, "popcorn", "Popcorn", DEF_POPCORN, t_Bool},
+ {&ejk1, "ejk1", "EJK1", DEF_EJK1, t_Bool},
+ {&ejk2, "ejk2", "EJK2", DEF_EJK2, t_Bool},
+ {&ejk3, "ejk3", "EJK3", DEF_EJK3, t_Bool},
+ {&ejk4, "ejk4", "EJK4", DEF_EJK4, t_Bool},
+ {&ejk5, "ejk5", "EJK5", DEF_EJK5, t_Bool},
+ {&ejk6, "ejk6", "EJK6", DEF_EJK6, t_Bool},
+ {&rr, "rr", "RR", DEF_RR, t_Bool},
+ {&jong, "jong", "Jong", DEF_JONG, t_Bool},
+ {&sine, "sine", "Sine", DEF_SINE, t_Bool}
+};
+static OptionStruct desc[] =
+{
+ {"-/+martin", "turn on/off sqrt format"},
+ {"-/+popcorn", "turn on/off Clifford A. Pickover's popcorn format"},
+ {"-/+ejk1", "turn on/off ejk1 format"},
+ {"-/+ejk2", "turn on/off ejk2 format"},
+ {"-/+ejk3", "turn on/off ejk3 format"},
+ {"-/+ejk4", "turn on/off ejk4 format"},
+ {"-/+ejk5", "turn on/off ejk5 format"},
+ {"-/+ejk6", "turn on/off ejk6 format"},
+ {"-/+rr", "turn on/off rr format"},
+ {"-/+jong", "turn on/off jong format"},
+ {"-/+sine", "turn on/off sine format"}
+};
+
+ENTRYPOINT ModeSpecOpt hop_opts =
+{sizeof opts / sizeof opts[0], opts, sizeof vars / sizeof vars[0], vars, desc};
+
+#ifdef USE_MODULES
+ModStruct hop_description =
+{"hop", "init_hop", "draw_hop", (char *) NULL,
+ "refresh_hop", "init_hop", "free_hop", &hop_opts,
+ 10000, 1000, 2500, 1, 64, 1.0, "",
+ "Shows real plane iterated fractals", 0, NULL};
+
+#endif
+
+#define MARTIN 0
+#define POPCORN 7
+#define SINE 8
+#define EJK1 1
+#define EJK2 2
+#define EJK3 9
+#define EJK4 3
+#define EJK5 4
+#define EJK6 10
+#define RR 5
+#define JONG 6
+#ifdef OFFENDING
+#define OPS 8 /* 8, 9, 10 might be too close to a swastika for some... */
+#else
+#define OPS 11
+#endif
+
+typedef struct {
+ int centerx, centery; /* center of the screen */
+ double a, b, c, d;
+ double i, j; /* hopalong parameters */
+ int inc;
+ int pix;
+ int op;
+ int count;
+ int bufsize;
+ XPoint *pointBuffer; /* pointer for XDrawPoints */
+} hopstruct;
+
+static hopstruct *hops = (hopstruct *) NULL;
+
+ENTRYPOINT void
+init_hop(ModeInfo * mi)
+{
+ Display *display = MI_DISPLAY(mi);
+ GC gc = MI_GC(mi);
+ double range;
+ hopstruct *hp;
+
+ MI_INIT (mi, hops);
+ hp = &hops[MI_SCREEN(mi)];
+
+ hp->centerx = MI_WIDTH(mi) / 2;
+ hp->centery = MI_HEIGHT(mi) / 2;
+ /* Make the other operations less common since they are less interesting */
+ if (MI_IS_FULLRANDOM(mi)) {
+ hp->op = NRAND(OPS);
+ } else {
+ if (martin)
+ hp->op = MARTIN;
+ else if (popcorn)
+ hp->op = POPCORN;
+ else if (ejk1)
+ hp->op = EJK1;
+ else if (ejk2)
+ hp->op = EJK2;
+ else if (ejk3)
+ hp->op = EJK3;
+ else if (ejk4)
+ hp->op = EJK4;
+ else if (ejk5)
+ hp->op = EJK5;
+ else if (ejk6)
+ hp->op = EJK6;
+ else if (rr)
+ hp->op = RR;
+ else if (jong)
+ hp->op = JONG;
+ else if (sine)
+ hp->op = SINE;
+ else
+ hp->op = NRAND(OPS);
+ }
+
+ range = sqrt((double) hp->centerx * hp->centerx +
+ (double) hp->centery * hp->centery) / (1.0 + LRAND() / MAXRAND);
+ hp->i = hp->j = 0.0;
+ hp->inc = (int) ((LRAND() / MAXRAND) * 200) - 100;
+#undef XMARTIN
+ switch (hp->op) {
+ case MARTIN:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 1500.0 + 40.0;
+ hp->b = (LRAND() / MAXRAND) * 17.0 + 3.0;
+ hp->c = (LRAND() / MAXRAND) * 3000.0 + 100.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 20.0;
+ hp->b = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 20.0;
+ if (LRAND() & 1)
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 20.0;
+ else
+ hp->c = 0.0;
+#endif
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "sqrt a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK1:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 500.0;
+ hp->c = (LRAND() / MAXRAND) * 100.0 + 10.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 30.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 40.0;
+#endif
+ hp->b = (LRAND() / MAXRAND) * 0.4;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk1 a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK2:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 500.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 30.0;
+#endif
+ hp->b = pow(10.0, 6.0 + (LRAND() / MAXRAND) * 24.0);
+ if (LRAND() & 1)
+ hp->b = -hp->b;
+ hp->c = pow(10.0, (LRAND() / MAXRAND) * 9.0);
+ if (LRAND() & 1)
+ hp->c = -hp->c;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk2 a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK3:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 500.0;
+ hp->c = (LRAND() / MAXRAND) * 80.0 + 30.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 30.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 70.0;
+#endif
+ hp->b = (LRAND() / MAXRAND) * 0.35 + 0.5;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk3 a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK4:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 1000.0;
+ hp->c = (LRAND() / MAXRAND) * 40.0 + 30.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 2.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 200.0;
+#endif
+ hp->b = (LRAND() / MAXRAND) * 9.0 + 1.0;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk4 a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK5:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 600.0;
+ hp->c = (LRAND() / MAXRAND) * 90.0 + 20.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 2.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 200.0;
+#endif
+ hp->b = (LRAND() / MAXRAND) * 0.3 + 0.1;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk5 a=%g, b=%g, c=%g\n", hp->a, hp->b, hp->c);
+ break;
+ case EJK6:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 100.0 + 550.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 30.0;
+#endif
+ hp->b = (LRAND() / MAXRAND) + 0.5;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "ejk6 a=%g, b=%g\n", hp->a, hp->b);
+ break;
+ case RR:
+#ifdef XMARTIN
+ hp->a = (LRAND() / MAXRAND) * 100.0;
+ hp->b = (LRAND() / MAXRAND) * 20.0;
+ hp->c = (LRAND() / MAXRAND) * 200.0;
+#else
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 40.0;
+ hp->b = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 200.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * range / 20.0;
+#endif
+ hp->d = (LRAND() / MAXRAND) * 0.9;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "rr a=%g, b=%g, c=%g, d=%g\n",
+ hp->a, hp->b, hp->c, hp->d);
+ break;
+ case POPCORN:
+ hp->a = 0.0;
+ hp->b = 0.0;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * 0.24 + 0.25;
+ hp->inc = 100;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "popcorn a=%g, b=%g, c=%g, d=%g\n",
+ hp->a, hp->b, hp->c, hp->d);
+ break;
+ case JONG:
+ hp->a = ((LRAND() / MAXRAND) * 2.0 - 1.0) * M_PI;
+ hp->b = ((LRAND() / MAXRAND) * 2.0 - 1.0) * M_PI;
+ hp->c = ((LRAND() / MAXRAND) * 2.0 - 1.0) * M_PI;
+ hp->d = ((LRAND() / MAXRAND) * 2.0 - 1.0) * M_PI;
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "jong a=%g, b=%g, c=%g, d=%g\n",
+ hp->a, hp->b, hp->c, hp->d);
+ break;
+ case SINE: /* MARTIN2 */
+#ifdef XMARTIN
+ hp->a = M_PI + ((LRAND() / MAXRAND) * 2.0 - 1.0) * 0.07;
+#else
+ hp->a = M_PI + ((LRAND() / MAXRAND) * 2.0 - 1.0) * 0.7;
+#endif
+ if (MI_IS_VERBOSE(mi))
+ (void) fprintf(stdout, "sine a=%g\n", hp->a);
+ break;
+ }
+ if (MI_NPIXELS(mi) > 2)
+ hp->pix = NRAND(MI_NPIXELS(mi));
+ hp->bufsize = MI_COUNT(mi);
+
+ if (hp->pointBuffer == NULL) {
+ if ((hp->pointBuffer = (XPoint *) malloc(hp->bufsize *
+ sizeof (XPoint))) == NULL)
+ return;
+ }
+
+ MI_CLEARWINDOW(mi);
+
+ XSetForeground(display, gc, MI_WHITE_PIXEL(mi));
+ hp->count = 0;
+}
+
+
+ENTRYPOINT void
+draw_hop(ModeInfo * mi)
+{
+ double oldj, oldi;
+ XPoint *xp;
+ int k;
+ hopstruct *hp;
+
+ if (hops == NULL)
+ return;
+ hp = &hops[MI_SCREEN(mi)];
+
+
+ if (hp->pointBuffer == NULL)
+ return;
+ xp = hp->pointBuffer;
+ k = hp->bufsize;
+
+ MI_IS_DRAWN(mi) = True;
+ hp->inc++;
+ if (MI_NPIXELS(mi) > 2) {
+ XSetForeground(MI_DISPLAY(mi), MI_GC(mi), MI_PIXEL(mi, hp->pix));
+ if (++hp->pix >= MI_NPIXELS(mi))
+ hp->pix = 0;
+ }
+ while (k--) {
+ oldj = hp->j;
+ switch (hp->op) {
+ case MARTIN: /* SQRT, MARTIN1 */
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj + ((hp->i < 0)
+ ? sqrt(fabs(hp->b * oldi - hp->c))
+ : -sqrt(fabs(hp->b * oldi - hp->c)));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK1:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i > 0) ? (hp->b * oldi - hp->c) :
+ -(hp->b * oldi - hp->c));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK2:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i < 0) ? log(fabs(hp->b * oldi - hp->c)) :
+ -log(fabs(hp->b * oldi - hp->c)));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK3:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i > 0) ? sin(hp->b * oldi) - hp->c :
+ -sin(hp->b * oldi) - hp->c);
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK4:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i > 0) ? sin(hp->b * oldi) - hp->c :
+ -sqrt(fabs(hp->b * oldi - hp->c)));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK5:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i > 0) ? sin(hp->b * oldi) - hp->c :
+ -(hp->b * oldi - hp->c));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case EJK6:
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - asin((hp->b * oldi) - (long) (hp->b * oldi));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case RR: /* RR1 */
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - ((hp->i < 0) ? -pow(fabs(hp->b * oldi - hp->c), hp->d) :
+ pow(fabs(hp->b * oldi - hp->c), hp->d));
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ case POPCORN:
+#define HVAL 0.05
+#define INCVAL 50
+ {
+ double tempi, tempj;
+
+ if (hp->inc >= 100)
+ hp->inc = 0;
+ if (hp->inc == 0) {
+ if (hp->a++ >= INCVAL) {
+ hp->a = 0;
+ if (hp->b++ >= INCVAL)
+ hp->b = 0;
+ }
+ hp->i = (-hp->c * INCVAL / 2 + hp->c * hp->a) * M_PI / 180.0;
+ hp->j = (-hp->c * INCVAL / 2 + hp->c * hp->b) * M_PI / 180.0;
+ }
+ tempi = hp->i - HVAL * sin(hp->j + tan(3.0 * hp->j));
+ tempj = hp->j - HVAL * sin(hp->i + tan(3.0 * hp->i));
+ xp->x = hp->centerx + (int) (MI_WIDTH(mi) / 40 * tempi);
+ xp->y = hp->centery + (int) (MI_HEIGHT(mi) / 40 * tempj);
+ hp->i = tempi;
+ hp->j = tempj;
+ }
+ break;
+ case JONG:
+ if (hp->centerx > 0)
+ oldi = hp->i + 4 * hp->inc / hp->centerx;
+ else
+ oldi = hp->i;
+ hp->j = sin(hp->c * hp->i) - cos(hp->d * hp->j);
+ hp->i = sin(hp->a * oldj) - cos(hp->b * oldi);
+ xp->x = hp->centerx + (int) (hp->centerx * (hp->i + hp->j) / 4.0);
+ xp->y = hp->centery - (int) (hp->centery * (hp->i - hp->j) / 4.0);
+ break;
+ case SINE: /* MARTIN2 */
+ oldi = hp->i + hp->inc;
+ hp->j = hp->a - hp->i;
+ hp->i = oldj - sin(oldi);
+ xp->x = hp->centerx + (int) (hp->i + hp->j);
+ xp->y = hp->centery - (int) (hp->i - hp->j);
+ break;
+ }
+ xp++;
+ }
+ XDrawPoints(MI_DISPLAY(mi), MI_WINDOW(mi), MI_GC(mi),
+ hp->pointBuffer, hp->bufsize, CoordModeOrigin);
+ if (++hp->count > MI_CYCLES(mi)) {
+ init_hop(mi);
+ }
+}
+
+ENTRYPOINT void
+free_hop(ModeInfo * mi)
+{
+ hopstruct *hp = &hops[MI_SCREEN(mi)];
+
+ if (hp->pointBuffer != NULL)
+ (void) free((void *) hp->pointBuffer);
+}
+
+#ifndef STANDALONE
+ENTRYPOINT void
+refresh_hop(ModeInfo * mi)
+{
+ MI_CLEARWINDOW(mi);
+}
+#endif
+
+XSCREENSAVER_MODULE_2 ("Hopalong", hopalong, hop)
+
+#endif /* MODE_hop */