/* -*- 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" \
"*fpsSolid: true \n" \
# define SMOOTH_COLORS
# define release_spiral 0
# 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", (char *) NULL,
"refresh_spiral", "init_spiral", "free_spiral", &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;
MI_INIT (mi, spirals);
sp = &spirals[MI_SCREEN(mi)];
#ifdef HAVE_JWXYZ
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
free_spiral(ModeInfo * mi)
{
spiralstruct *sp;
if (spirals == NULL)
return;
sp = &spirals[MI_SCREEN(mi)];
if (sp->traildots)
(void) free((void *) sp->traildots);
}
#ifndef STANDALONE
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;
}
#endif
XSCREENSAVER_MODULE ("Spiral", spiral)
#endif /* MODE_spiral */
