--- /dev/null
+/* xscreensaver, Copyright (c) 1997, 1998 Jamie Zawinski <jwz@jwz.org>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation. No representations are made about the suitability of this
+ * software for any purpose. It is provided "as is" without express or
+ * implied warranty.
+ */
+
+#include <math.h>
+#include <sys/time.h> /* for gettimeofday() */
+#include "screenhack.h"
+#include "spline.h"
+
+
+static Colormap cmap;
+static Bool cycle_p;
+static XColor *colors;
+static int ncolors;
+static int fg_index;
+static GC gc;
+
+#define SCALE 1000 /* fixed-point math, for sub-pixel motion */
+
+
+#define RAND(n) ((long) ((random() & 0x7fffffff) % ((long) (n))))
+#define RANDSIGN() ((random() & 1) ? 1 : -1)
+
+enum starfish_mode {
+ pulse,
+ zoom
+};
+
+
+struct starfish {
+ enum starfish_mode mode;
+ Bool blob_p;
+ int skip;
+ long x, y; /* position of midpoint */
+ double th; /* angle of rotation */
+ double rotv; /* rotational velocity */
+ double rota; /* rotational acceleration */
+ long elasticity; /* how fast it deforms: radial velocity */
+ double rot_max;
+ long min_r, max_r; /* radius range */
+ int npoints; /* control points */
+ long *r; /* radii */
+ spline *spline;
+ XPoint *prev;
+ int n_prev;
+};
+
+static struct starfish *
+make_starfish (int maxx, int maxy, int size)
+{
+ struct starfish *s = (struct starfish *) calloc(1, sizeof(*s));
+ int i;
+ int mid;
+
+ s->blob_p = get_boolean_resource ("blob", "Blob");
+ s->elasticity = SCALE * get_float_resource ("thickness", "Thickness");
+
+ if (s->elasticity == 0)
+ /* bell curve from 0-15, avg 7.5 */
+ s->elasticity = RAND(5*SCALE) + RAND(5*SCALE) + RAND(5*SCALE);
+
+ s->rotv = get_float_resource ("rotation", "Rotation");
+ if (s->rotv == -1)
+ /* bell curve from 0-12 degrees, avg 6 */
+ s->rotv = frand(4) + frand(4) + frand(4);
+
+ s->rotv /= 360; /* convert degrees to ratio */
+
+ if (s->blob_p)
+ {
+ s->elasticity *= 3;
+ s->rotv *= 3;
+ }
+
+ s->rot_max = s->rotv * 2;
+ s->rota = 0.0004 + frand(0.0002);
+
+
+ if (! (random() % 20))
+ size *= frand(0.35) + frand(0.35) + 0.3;
+
+ {
+ static char skips[] = { 2, 2, 2, 2,
+ 3, 3, 3,
+ 6, 6,
+ 12 };
+ s->skip = skips[random() % sizeof(skips)];
+ }
+
+ if (! (random() % (s->skip == 2 ? 3 : 12)))
+ s->mode = zoom;
+ else
+ s->mode = pulse;
+
+ maxx *= SCALE;
+ maxy *= SCALE;
+ size *= SCALE;
+
+ s->max_r = size;
+ s->min_r = 0;
+
+ if (s->min_r < (5*SCALE)) s->min_r = (5*SCALE);
+ mid = ((s->min_r + s->max_r) / 2);
+
+ s->x = maxx/2;
+ s->y = maxy/2;
+
+ s->th = frand(M_PI+M_PI) * RANDSIGN();
+
+ {
+ static char sizes[] = { 3, 3, 3, 3, 3,
+ 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5,
+ 8, 8, 8,
+ 10,
+ 35 };
+ int nsizes = sizeof(sizes);
+ if (s->skip > 3)
+ nsizes -= 4;
+ s->npoints = s->skip * sizes[random() % nsizes];
+ }
+
+ s->spline = make_spline (s->npoints);
+ s->r = (long *) malloc (sizeof(*s->r) * s->npoints);
+
+ for (i = 0; i < s->npoints; i++)
+ s->r[i] = ((i % s->skip) == 0) ? 0 : size;
+
+ return s;
+}
+
+
+static void
+free_starfish (struct starfish *s)
+{
+ if (s->r) free (s->r);
+ if (s->prev) free (s->prev);
+ if (s->spline)
+ {
+ if (s->spline->control_x) free (s->spline->control_x);
+ if (s->spline->control_y) free (s->spline->control_y);
+ if (s->spline->points) free (s->spline->points);
+ free (s->spline);
+ }
+ free (s);
+}
+
+
+static void
+throb_starfish (struct starfish *s)
+{
+ int i;
+ double frac = ((M_PI+M_PI) / s->npoints);
+
+ for (i = 0; i < s->npoints; i++)
+ {
+ long r = s->r[i];
+ long ra = (r > 0 ? r : -r);
+ double th = (s->th > 0 ? s->th : -s->th);
+ long x, y;
+ long elasticity = s->elasticity;
+
+ /* place control points evenly around perimiter, shifted by theta */
+ x = s->x + ra * cos (i * frac + th);
+ y = s->y + ra * sin (i * frac + th);
+
+ s->spline->control_x[i] = x / SCALE;
+ s->spline->control_y[i] = y / SCALE;
+
+ if (s->mode == zoom && ((i % s->skip) == 0))
+ continue;
+
+ /* Slow down near the end points: move fastest in the middle. */
+ {
+ double ratio = (double)ra / (double)(s->max_r - s->min_r);
+ if (ratio > 0.5) ratio = 1-ratio; /* flip */
+ ratio *= 2; /* normalize */
+ ratio = (ratio * 0.9) + 0.1; /* fudge */
+ elasticity *= ratio;
+ }
+
+
+ /* Increase/decrease radius by elasticity */
+ ra += (r >= 0 ? elasticity : -elasticity);
+ if ((i % s->skip) == 0)
+ ra += (elasticity / 2);
+
+ r = ra * (r >= 0 ? 1 : -1);
+
+ /* If we've reached the end (too long or too short) reverse direction. */
+ if ((ra > s->max_r && r >= 0) ||
+ (ra < s->min_r && r < 0))
+ r = -r;
+
+ s->r[i] = r;
+ }
+}
+
+
+static void
+spin_starfish (struct starfish *s)
+{
+ double th = s->th;
+ if (th < 0)
+ th = -(th + s->rotv);
+ else
+ th += s->rotv;
+
+ if (th > (M_PI+M_PI))
+ th -= (M_PI+M_PI);
+ else if (th < 0)
+ th += (M_PI+M_PI);
+
+ s->th = (s->th > 0 ? th : -th);
+
+ s->rotv += s->rota;
+
+ if (s->rotv > s->rot_max ||
+ s->rotv < -s->rot_max)
+ {
+ s->rota = -s->rota;
+ }
+ /* If it stops, start it going in the other direction. */
+ else if (s->rotv < 0)
+ {
+ if (random() & 1)
+ {
+ /* keep going in the same direction */
+ s->rotv = 0;
+ if (s->rota < 0)
+ s->rota = -s->rota;
+ }
+ else
+ {
+ /* reverse gears */
+ s->rotv = -s->rotv;
+ s->rota = -s->rota;
+ s->th = -s->th;
+ }
+ }
+
+
+ /* Alter direction of rotational acceleration randomly. */
+ if (! (random() % 120))
+ s->rota = -s->rota;
+
+ /* Change acceleration very occasionally. */
+ if (! (random() % 200))
+ {
+ if (random() & 1)
+ s->rota *= 1.2;
+ else
+ s->rota *= 0.8;
+ }
+}
+
+
+static void
+draw_starfish (Display *dpy, Drawable drawable, GC gc, struct starfish *s,
+ Bool fill_p)
+{
+ compute_closed_spline (s->spline);
+ if (s->prev)
+ {
+ XPoint *points = (XPoint *)
+ malloc (sizeof(XPoint) * (s->n_prev + s->spline->n_points + 2));
+ int i = s->spline->n_points;
+ int j = s->n_prev;
+ memcpy (points, s->spline->points, (i * sizeof(*points)));
+ memcpy (points+i, s->prev, (j * sizeof(*points)));
+
+ if (s->blob_p)
+ XClearWindow (dpy, drawable);
+ XFillPolygon (dpy, drawable, gc, points, i+j, Complex, CoordModeOrigin);
+ free (points);
+
+ free (s->prev);
+ s->prev = 0;
+ }
+
+ s->prev = (XPoint *) malloc (s->spline->n_points * sizeof(XPoint));
+ memcpy (s->prev, s->spline->points, s->spline->n_points * sizeof(XPoint));
+ s->n_prev = s->spline->n_points;
+
+#ifdef DEBUG
+ if (s->blob_p)
+ {
+ int i;
+ for (i = 0; i < s->npoints; i++)
+ XDrawLine (dpy, drawable, gc, s->x/SCALE, s->y/SCALE,
+ s->spline->control_x[i], s->spline->control_y[i]);
+ }
+#endif
+}
+
+
+static struct starfish *
+make_window_starfish (Display *dpy, Window window)
+{
+ XWindowAttributes xgwa;
+ int size;
+ Bool blob_p = get_boolean_resource ("blob", "Blob");
+ XGetWindowAttributes (dpy, window, &xgwa);
+ size = (xgwa.width < xgwa.height ? xgwa.width : xgwa.height);
+ if (blob_p) size /= 2;
+ else size *= 1.3;
+ return make_starfish (xgwa.width, xgwa.height, size);
+}
+
+
+static struct starfish *
+init_starfish (Display *dpy, Window window)
+{
+ static Bool first_time = True;
+ XGCValues gcv;
+ XWindowAttributes xgwa;
+ Bool blob_p = get_boolean_resource ("blob", "Blob");
+ XGetWindowAttributes (dpy, window, &xgwa);
+
+ cmap = xgwa.colormap;
+ cycle_p = get_boolean_resource ("cycle", "Cycle");
+
+ if (!first_time)
+ {
+ if (colors && ncolors)
+ free_colors (dpy, cmap, colors, ncolors);
+ if (colors)
+ free (colors);
+ colors = 0;
+ }
+
+ ncolors = get_integer_resource ("colors", "Colors");
+ if (ncolors < 2) ncolors = 2;
+ if (ncolors <= 2) mono_p = True;
+
+ if (mono_p)
+ colors = 0;
+ else
+ colors = (XColor *) malloc(sizeof(*colors) * (ncolors+1));
+
+ if (mono_p || blob_p)
+ cycle_p = False;
+
+ if (mono_p)
+ ;
+ else if (random() % 3)
+ make_smooth_colormap (dpy, xgwa.visual, cmap, colors, &ncolors,
+ True, &cycle_p, True);
+ else
+ make_uniform_colormap (dpy, xgwa.visual, cmap, colors, &ncolors,
+ True, &cycle_p, True);
+
+ if (ncolors < 2) ncolors = 2;
+ if (ncolors <= 2) mono_p = True;
+
+ if (mono_p) cycle_p = False;
+
+ fg_index = 0;
+
+ if (!mono_p && !blob_p)
+ {
+ gcv.foreground = colors[fg_index].pixel;
+ XSetWindowBackground (dpy, window, gcv.foreground);
+ }
+
+ if (first_time)
+ {
+ XClearWindow (dpy, window);
+ first_time = False;
+ }
+
+ gcv.fill_rule = EvenOddRule;
+ gc = XCreateGC (dpy, window, GCForeground | GCFillRule, &gcv);
+
+ return make_window_starfish (dpy, window);
+}
+
+
+
+static void
+run_starfish (Display *dpy, Window window, struct starfish *s)
+{
+ throb_starfish (s);
+ spin_starfish (s);
+ draw_starfish (dpy, window, gc, s, False);
+
+ if (mono_p)
+ {
+ static Bool init = False;
+ static unsigned long black, white;
+ if (!init)
+ {
+ black = get_pixel_resource ("background", "Background", dpy, cmap);
+ white = get_pixel_resource ("foreground", "Foreground", dpy, cmap);
+ init = True;
+ fg_index = white;
+ XSetForeground (dpy, gc, fg_index);
+ }
+ else if (!s->blob_p)
+ {
+ fg_index = (fg_index == black ? white : black);
+ XSetForeground (dpy, gc, fg_index);
+ }
+ }
+ else
+ {
+ fg_index = (fg_index + 1) % ncolors;
+ XSetForeground (dpy, gc, colors [fg_index].pixel);
+ }
+}
+
+
+
+\f
+char *progclass = "Starfish";
+
+char *defaults [] = {
+ ".background: black",
+ ".foreground: white",
+ "*delay: 10000",
+ "*cycleDelay: 100000",
+ "*thickness: 0", /* pixels, 0 = random */
+ "*rotation: -1", /* degrees, -1 = "random" */
+ "*colors: 200",
+ "*cycle: true",
+ "*duration: 30",
+ "*delay2: 5",
+ "*blob: false",
+ 0
+};
+
+XrmOptionDescRec options [] = {
+ { "-delay", ".delay", XrmoptionSepArg, 0 },
+ { "-delay2", ".delay2", XrmoptionSepArg, 0 },
+ { "-cycle-delay", ".cycleDelay", XrmoptionSepArg, 0 },
+ { "-thickness", ".thickness", XrmoptionSepArg, 0 },
+ { "-rotation", ".rotation", XrmoptionSepArg, 0 },
+ { "-colors", ".colors", XrmoptionSepArg, 0 },
+ { "-cycle", ".cycle", XrmoptionNoArg, "True" },
+ { "-no-cycle", ".cycle", XrmoptionNoArg, "False" },
+ { "-duration", ".duration", XrmoptionSepArg, 0 },
+ { "-blob", ".blob", XrmoptionNoArg, "True" },
+ { "-no-blob", ".blob", XrmoptionNoArg, "False" },
+ { 0, 0, 0, 0 }
+};
+
+void
+screenhack (Display *dpy, Window window)
+{
+ struct starfish *s = init_starfish (dpy, window);
+ int delay = get_integer_resource ("delay", "Delay");
+ int delay2 = get_integer_resource ("delay2", "Delay") * 1000000;
+ int cycle_delay = get_integer_resource ("cycleDelay", "Delay");
+ int duration = get_seconds_resource ("duration", "Seconds");
+ Bool blob_p = get_boolean_resource ("blob", "Blob");
+ time_t start = time ((time_t) 0);
+ time_t now;
+ int direction = (random() % 1) ? 1 : -1;
+
+ if (blob_p)
+ delay *= 3;
+
+ while (1)
+ {
+ run_starfish (dpy, window, s);
+ XSync (dpy, False);
+
+ screenhack_handle_events (dpy);
+ if (cycle_p && cycle_delay)
+ {
+ if (cycle_delay <= delay)
+ {
+ int i = 0;
+ while (i < delay)
+ {
+ rotate_colors (dpy, cmap, colors, ncolors, direction);
+ usleep(cycle_delay);
+ i += cycle_delay;
+ }
+ }
+ else
+ {
+ static long tick = 0;
+ if (tick >= cycle_delay)
+ {
+ rotate_colors (dpy, cmap, colors, ncolors, direction);
+ tick = 0;
+ }
+ if (delay)
+ usleep(delay);
+ tick += delay;
+ }
+
+ if (! (random() % 1000))
+ direction = -direction;
+ }
+ else if (delay)
+ usleep (delay);
+
+ if (duration > 0)
+ {
+ now = time ((time_t) 0);
+ if (start + duration < now)
+ {
+ start = now;
+
+ free_starfish (s);
+
+ if (delay2 && !blob_p && cycle_p)
+ {
+ int i = 0;
+ while (i < delay2)
+ {
+ rotate_colors (dpy, cmap, colors, ncolors, direction);
+ screenhack_handle_events (dpy);
+ usleep(cycle_delay);
+ i += cycle_delay;
+ }
+ }
+
+ /* Every now and then, pick new colors; otherwise, just build
+ a new starfish with the current colors. */
+ if (! (random () % 10))
+ s = init_starfish (dpy, window);
+ else
+ s = make_window_starfish(dpy, window);
+ }
+ }
+ }
+}
projects / xscreensaver / blobdiff