~ubuntu-branches/ubuntu/intrepid/xscreensaver/intrepid

/* -*- Mode: C; tab-width: 4 -*- */

/* spiral --- spiraling dots */

#if 0

static const char sccsid[] = "@(#)spiral.c	5.00 2000/11/01 xlockmore";

#endif

/*-

 * Copyright (c) 1994 by Darrick Brown.

 *

 * 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:

 * 01-Nov-2000: Allocation checks

 * 10-May-1997: jwz@jwz.org: turned into a standalone program.

 * 24-Jul-1995: Fix to allow cycles not to have an arbitrary value by

 *              Peter Schmitzberger (schmitz@coma.sbg.ac.at).

 * 06-Mar-1995: Finished cleaning up and final testing.

 * 03-Mar-1995: Cleaned up code.

 * 12-Jul-1994: Written.

 *

 * Low CPU usage mode.

 * Idea based on a graphics demo I saw a *LONG* time ago.

 */

#ifdef STANDALONE

# define MODE_spiral

#define DEFAULTS	"*delay: 50000 \n" \

					"*count: 40 \n" \

					"*cycles: 350 \n" \

					"*ncolors: 64 \n"

# define SMOOTH_COLORS

# define reshape_spiral 0

# define spiral_handle_event 0

# include "xlockmore.h"		/* from the xscreensaver distribution */

#else /* !STANDALONE */

# include "xlock.h"		/* from the xlockmore distribution */

#endif /* !STANDALONE */

#ifdef MODE_spiral

ENTRYPOINT ModeSpecOpt spiral_opts =

{0, (XrmOptionDescRec *) NULL, 0, (argtype *) NULL, (OptionStruct *) NULL};

#ifdef USE_MODULES

ModStruct   spiral_description =

{"spiral", "init_spiral", "draw_spiral", "release_spiral",

 "refresh_spiral", "init_spiral", (char *) NULL, &spiral_opts,

 5000, -40, 350, 1, 64, 1.0, "",

 "Shows a helical locus of points", 0, NULL};

#endif

#define MAXTRAIL 512		/* The length of the trail */

#define MAXDOTS 40

#define MINDOTS 1

#define TWOPI (2.0*M_PI)	/* for convienence */

#define JAGGINESS 4		/* This sets the "Craziness" of the spiral (I like 4) */

#define SPEED 2.0

/* How many segments to draw per cycle when redrawing */

#define REDRAWSTEP 3

typedef struct {

	float       hx, hy, ha, hr;

} Traildots;

typedef struct {

	Traildots  *traildots;

	float       cx, cy;

	float       angle;

	float       radius;

	float       dr, da;

	float       dx, dy;

	int         erase;

	int         inc;

	float       colors;

	int         width, height;

	float       top, bottom, left, right;

	int         dots, nlength;

	int         redrawing, redrawpos;

} spiralstruct;

static spiralstruct *spirals = (spiralstruct *) NULL;

static void draw_dots(ModeInfo * mi, int in);

#define TFX(sp,x) ((int)((x/sp->right)*(float)sp->width))

#define TFY(sp,y) ((int)((y/sp->top)*(float)sp->height))

static void

draw_dots(ModeInfo * mi, int in)

{

	float       i, inc;

	float       x, y;

	spiralstruct *sp = &spirals[MI_SCREEN(mi)];

	inc = TWOPI / (float) sp->dots;

	for (i = 0.0; i < TWOPI; i += inc) {

		x = sp->traildots[in].hx + COSF(i + sp->traildots[in].ha) *

			sp->traildots[in].hr;

		y = sp->traildots[in].hy + SINF(i + sp->traildots[in].ha) *

			sp->traildots[in].hr;

		XDrawPoint(MI_DISPLAY(mi), MI_WINDOW(mi), MI_GC(mi),

			   TFX(sp, x), TFY(sp, y));

	}

}

ENTRYPOINT void

init_spiral(ModeInfo * mi)

{

	spiralstruct *sp;

	int         i;

	if (spirals == NULL) {

		if ((spirals = (spiralstruct *) calloc(MI_NUM_SCREENS(mi),

					     sizeof (spiralstruct))) == NULL)

			return;

	}

	sp = &spirals[MI_SCREEN(mi)];

#ifdef HAVE_COCOA

    jwxyz_XSetAntiAliasing (MI_DISPLAY(mi), MI_GC(mi),  False);

#endif

	sp->width = MI_WIDTH(mi);

	sp->height = MI_HEIGHT(mi);

	MI_CLEARWINDOW(mi);

	/* Init */

	sp->nlength = MI_CYCLES(mi);

	if (!sp->traildots)

		if ((sp->traildots = (Traildots *) malloc(sp->nlength *

				sizeof (Traildots))) == NULL) {

			return;

		}

	/* initialize the allocated array */

	for (i = 0; i < sp->nlength; i++) {

		sp->traildots[i].hx = 0.0;

		sp->traildots[i].hy = 0.0;

		sp->traildots[i].ha = 0.0;

		sp->traildots[i].hr = 0.0;

	}

	sp->redrawing = 0;

	/* keep the window parameters proportional */

	sp->top = 10000.0;

	sp->bottom = 0;

	sp->right = (float) (sp->width) / (float) (sp->height) * (10000.0);

	sp->left = 0;

	/* assign the initial values */

	sp->cx = (float) (5000.0 - NRAND(2000)) / 10000.0 * sp->right;

	sp->cy = (float) (5000.0 - NRAND(2000));

	sp->radius = (float) (NRAND(200) + 200);

	sp->angle = 0.0;

	sp->dx = (float) (10 - NRAND(20)) * SPEED;

	sp->dy = (float) (10 - NRAND(20)) * SPEED;

	sp->dr = (float) ((NRAND(10) + 4) * (1 - (LRAND() & 1) * 2));

	sp->da = (float) NRAND(360) / 7200.0 + 0.01;

	if (MI_NPIXELS(mi) > 2)

		sp->colors = (float) NRAND(MI_NPIXELS(mi));

	sp->erase = 0;

	sp->inc = 0;

	sp->traildots[sp->inc].hx = sp->cx;

	sp->traildots[sp->inc].hy = sp->cy;

	sp->traildots[sp->inc].ha = sp->angle;

	sp->traildots[sp->inc].hr = sp->radius;

	sp->inc++;

	sp->dots = MI_COUNT(mi);

	if (sp->dots < -MINDOTS)

		sp->dots = NRAND(sp->dots - MINDOTS + 1) + MINDOTS;

	/* Absolute minimum */

	if (sp->dots < MINDOTS)

		sp->dots = MINDOTS;

}

ENTRYPOINT void

draw_spiral(ModeInfo * mi)

{

	Display    *display = MI_DISPLAY(mi);

	GC          gc = MI_GC(mi);

	int         i, j;

	spiralstruct *sp;

	if (spirals == NULL)

		return;

	sp = &spirals[MI_SCREEN(mi)];

	if (sp->traildots == NULL)

		return;

	MI_IS_DRAWN(mi) = True;

	if (sp->erase == 1) {

		XSetForeground(display, gc, MI_BLACK_PIXEL(mi));

		draw_dots(mi, sp->inc);

	}

	sp->cx += sp->dx;

	sp->traildots[sp->inc].hx = sp->cx;

	if ((sp->cx > 9000.0) || (sp->cx < 1000.0))

		sp->dx *= -1.0;

	sp->cy += sp->dy;

	sp->traildots[sp->inc].hy = sp->cy;

	if ((sp->cy > 9000.0) || (sp->cy < 1000.0))

		sp->dy *= -1.0;

	sp->radius += sp->dr;

	sp->traildots[sp->inc].hr = sp->radius;

	if ((sp->radius > 2500.0) && (sp->dr > 0.0))

		sp->dr *= -1.0;

	else if ((sp->radius < 50.0) && (sp->radius < 0.0))

		sp->dr *= -1.0;

	/* Randomly give some variations to:  */

	/* spiral direction (if it is within the boundaries) */

	if ((NRAND(3000) < 1 * JAGGINESS) &&

	    (((sp->cx > 2000.0) && (sp->cx < 8000.0)) &&

	     ((sp->cy > 2000.0) && (sp->cy < 8000.0)))) {

		sp->dx = (float) (10 - NRAND(20)) * SPEED;

		sp->dy = (float) (10 - NRAND(20)) * SPEED;

	}

	/* The speed of the change in size of the spiral */

	if (NRAND(3000) < 1 * JAGGINESS) {

		if (LRAND() & 1)

			sp->dr += (float) (NRAND(3) + 1);

		else

			sp->dr -= (float) (NRAND(3) + 1);

		/* don't let it get too wild */

		if (sp->dr > 18.0)

			sp->dr = 18.0;

		else if (sp->dr < 4.0)

			sp->dr = 4.0;

	}

	/* The speed of rotation */

	if (NRAND(3000) < 1 * JAGGINESS)

		sp->da = (float) NRAND(360) / 7200.0 + 0.01;

	/* Reverse rotation */

	if (NRAND(3000) < 1 * JAGGINESS)

		sp->da *= -1.0;

	sp->angle += sp->da;

	sp->traildots[sp->inc].ha = sp->angle;

	if (sp->angle > TWOPI)

		sp->angle -= TWOPI;

	else if (sp->angle < 0.0)

		sp->angle += TWOPI;

	sp->colors += (float) MI_NPIXELS(mi) / ((float) (2 * sp->nlength));

	if (sp->colors >= (float) MI_NPIXELS(mi))

		sp->colors = 0.0;

	if (MI_NPIXELS(mi) > 2)

		XSetForeground(display, gc, MI_PIXEL(mi, (int) sp->colors));

	else

		XSetForeground(display, gc, MI_WHITE_PIXEL(mi));

	draw_dots(mi, sp->inc);

	sp->inc++;

	if (sp->inc > sp->nlength - 1) {

		sp->inc -= sp->nlength;

		sp->erase = 1;

	}

	if (sp->redrawing) {

		for (i = 0; i < REDRAWSTEP; i++) {

			j = (sp->inc - sp->redrawpos + sp->nlength) % sp->nlength;

			draw_dots(mi, j);

			if (++(sp->redrawpos) >= sp->nlength) {

				sp->redrawing = 0;

				break;

			}

		}

	}

}

ENTRYPOINT void

release_spiral(ModeInfo * mi)

{

	if (spirals != NULL) {

		int         screen;

		for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++) {

			spiralstruct *sp = &spirals[screen];

			if (sp->traildots)

				(void) free((void *) sp->traildots);

		}

		(void) free((void *) spirals);

		spirals = (spiralstruct *) NULL;

	}

}

ENTRYPOINT void

refresh_spiral(ModeInfo * mi)

{

	spiralstruct *sp;

	if (spirals == NULL)

		return;

	sp = &spirals[MI_SCREEN(mi)];

	MI_CLEARWINDOW(mi);

	sp->redrawing = 1;

	sp->redrawpos = 0;

}

XSCREENSAVER_MODULE ("Spiral", spiral)

#endif /* MODE_spiral */