/*

 * Copyright (c) 1988-91 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.

 */

/*

 * Copyright 1994 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 *

 *

 */

/*-

 * swarm.c - swarm of bees for xlock, the X Window System lockscreen.

 *

 * Copyright (c) 1991 by Patrick J. Naughton.

 *

 * Revision History:

 * 31-Aug-90: Adapted from xswarm by Jeff Butterworth. ([email protected])

 */

#include "xlock.h"

#define TIMES	4		/* number of time positions recorded */

#define BEEACC	3		/* acceleration of bees */

#define WASPACC 5		/* maximum acceleration of wasp */

#define BEEVEL	11		/* maximum bee velocity */

#define WASPVEL 12		/* maximum wasp velocity */

#define BORDER	50		/* wasp won't go closer than this to the edge */

/* Macros */

#define X(t,b)	(sp->x[(t)*sp->beecount+(b)])

#define Y(t,b)	(sp->y[(t)*sp->beecount+(b)])

#define RAND(v)	((random()%(v))-((v)/2))	/* random number around 0 */

typedef struct {

    int         pix;

    long        startTime;

    int         width;

    int         height;

    int         beecount;	/* number of bees */

    XSegment   *segs;		/* bee lines */

    XSegment   *old_segs;	/* old bee lines */

    short      *x;

    short      *y;		/* bee positions x[time][bee#] */

    short      *xv;

    short      *yv;		/* bee velocities xv[bee#] */

    short       wx[3];

    short       wy[3];

    short       wxv;

    short       wyv;

}           swarmstruct;

extern XColor ssblack[];

extern XColor sswhite[];

static swarmstruct swarms[MAXSCREENS];

void

initswarm(win)

    Window      win;

{

    XWindowAttributes xgwa;

    swarmstruct *sp = &swarms[screen];

    int         b;

    sp->startTime = seconds();

    sp->beecount = batchcount;

    XGetWindowAttributes(dsp, win, &xgwa);

    sp->width = xgwa.width;

    sp->height = xgwa.height;

    /* Clear the background. */

    XSetForeground(dsp, Scr[screen].gc, ssblack[screen].pixel);

    XFillRectangle(dsp, win, Scr[screen].gc, 0, 0, sp->width, sp->height);

    /* Allocate memory. */

    if (!sp->segs) {

	sp->segs = (XSegment *) malloc(sizeof(XSegment) * sp->beecount);

	sp->old_segs = (XSegment *) malloc(sizeof(XSegment) * sp->beecount);

	sp->x = (short *) malloc(sizeof(short) * sp->beecount * TIMES);

	sp->y = (short *) malloc(sizeof(short) * sp->beecount * TIMES);

	sp->xv = (short *) malloc(sizeof(short) * sp->beecount);

	sp->yv = (short *) malloc(sizeof(short) * sp->beecount);

    }

    /* Initialize point positions, velocities, etc. */

    /* wasp */

    sp->wx[0] = BORDER + random() % (sp->width - 2 * BORDER);

    sp->wy[0] = BORDER + random() % (sp->height - 2 * BORDER);

    sp->wx[1] = sp->wx[0];

    sp->wy[1] = sp->wy[0];

    sp->wxv = 0;

    sp->wyv = 0;

    /* bees */

    for (b = 0; b < sp->beecount; b++) {

	X(0, b) = random() % sp->width;

	X(1, b) = X(0, b);

	Y(0, b) = random() % sp->height;

	Y(1, b) = Y(0, b);

	sp->xv[b] = RAND(7);

	sp->yv[b] = RAND(7);

    }

}

void

drawswarm(win)

    Window      win;

{

    swarmstruct *sp = &swarms[screen];

    int         b;

    /* <=- Wasp -=> */

    /* Age the arrays. */

    sp->wx[2] = sp->wx[1];

    sp->wx[1] = sp->wx[0];

    sp->wy[2] = sp->wy[1];

    sp->wy[1] = sp->wy[0];

    /* Accelerate */

    sp->wxv += RAND(WASPACC);

    sp->wyv += RAND(WASPACC);

    /* Speed Limit Checks */

    if (sp->wxv > WASPVEL)

	sp->wxv = WASPVEL;

    if (sp->wxv < -WASPVEL)

	sp->wxv = -WASPVEL;

    if (sp->wyv > WASPVEL)

	sp->wyv = WASPVEL;

    if (sp->wyv < -WASPVEL)

	sp->wyv = -WASPVEL;

    /* Move */

    sp->wx[0] = sp->wx[1] + sp->wxv;

    sp->wy[0] = sp->wy[1] + sp->wyv;

    /* Bounce Checks */

    if ((sp->wx[0] < BORDER) || (sp->wx[0] > sp->width - BORDER - 1)) {

	sp->wxv = -sp->wxv;

	sp->wx[0] += sp->wxv;

    }

    if ((sp->wy[0] < BORDER) || (sp->wy[0] > sp->height - BORDER - 1)) {

	sp->wyv = -sp->wyv;

	sp->wy[0] += sp->wyv;

    }

    /* Don't let things settle down. */

    sp->xv[random() % sp->beecount] += RAND(3);

    sp->yv[random() % sp->beecount] += RAND(3);

    /* <=- Bees -=> */

    for (b = 0; b < sp->beecount; b++) {

	int         distance,

	            dx,

	            dy;

	/* Age the arrays. */

	X(2, b) = X(1, b);

	X(1, b) = X(0, b);

	Y(2, b) = Y(1, b);

	Y(1, b) = Y(0, b);

	/* Accelerate */

	dx = sp->wx[1] - X(1, b);

	dy = sp->wy[1] - Y(1, b);

	distance = abs(dx) + abs(dy);	/* approximation */

	if (distance == 0)

	    distance = 1;

	sp->xv[b] += (dx * BEEACC) / distance;

	sp->yv[b] += (dy * BEEACC) / distance;

	/* Speed Limit Checks */

	if (sp->xv[b] > BEEVEL)

	    sp->xv[b] = BEEVEL;

	if (sp->xv[b] < -BEEVEL)

	    sp->xv[b] = -BEEVEL;

	if (sp->yv[b] > BEEVEL)

	    sp->yv[b] = BEEVEL;

	if (sp->yv[b] < -BEEVEL)

	    sp->yv[b] = -BEEVEL;

	/* Move */

	X(0, b) = X(1, b) + sp->xv[b];

	Y(0, b) = Y(1, b) + sp->yv[b];

	/* Fill the segment lists. */

	sp->segs[b].x1 = X(0, b);

	sp->segs[b].y1 = Y(0, b);

	sp->segs[b].x2 = X(1, b);

	sp->segs[b].y2 = Y(1, b);

	sp->old_segs[b].x1 = X(1, b);

	sp->old_segs[b].y1 = Y(1, b);

	sp->old_segs[b].x2 = X(2, b);

	sp->old_segs[b].y2 = Y(2, b);

    }

    XSetForeground(dsp, Scr[screen].gc, ssblack[screen].pixel);

    XDrawLine(dsp, win, Scr[screen].gc,

	      sp->wx[1], sp->wy[1], sp->wx[2], sp->wy[2]);

    XDrawSegments(dsp, win, Scr[screen].gc, sp->old_segs, sp->beecount);

    XSetForeground(dsp, Scr[screen].gc, sswhite[screen].pixel);

    XDrawLine(dsp, win, Scr[screen].gc,

	      sp->wx[0], sp->wy[0], sp->wx[1], sp->wy[1]);

    if (!mono && Scr[screen].npixels > 2) {

	XSetForeground(dsp, Scr[screen].gc, Scr[screen].pixels[sp->pix]);

	if (++sp->pix >= Scr[screen].npixels)

	    sp->pix = 0;

    }

    XDrawSegments(dsp, win, Scr[screen].gc, sp->segs, sp->beecount);

}