--- /dev/null
+/* imsmap, Copyright (c) 1992 Juergen Nickelsen <nickel@cs.tu-berlin.de>
+ * Derived from code by Markus Schirmer, TU Berlin.
+ *
+ * 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.
+ *
+ * Revision History:
+ * 24-aug-92: jwz: hacked.
+ * 17-May-97: jwz: hacked more.
+ */
+
+#include <stdio.h>
+#include <math.h>
+#include <sys/time.h> /* for gettimeofday() */
+
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+#include "screenhack.h"
+
+#define NSTEPS 7
+#define COUNT (1 << NSTEPS)
+#define CELL(c, r) cell[((unsigned int)(c)) + ((unsigned int) (r)) * xmax]
+
+static enum mode_t { MODE_H, MODE_S, MODE_V, MODE_RANDOM } mode;
+
+static GC gc, gc2;
+static XWindowAttributes xgwa;
+
+#if defined(sun) && !__STDC__ /* sun cc doesn't know "signed char" */
+#define signed /**/
+#endif
+
+static Colormap cmap;
+static int ncolors;
+static XColor *colors;
+static Bool cycle_p;
+static int cycle_direction;
+static Bool extra_krinkly_p;
+
+static int delay, cycle_delay;
+static signed char *cell = NULL;
+static int xmax, ymax;
+static int iterations;
+
+static void
+init_map (Display *dpy, Window window)
+{
+ unsigned long fg_pixel = 0, bg_pixel = 0;
+ int fg_h, bg_h;
+ double fg_s, fg_v, bg_s, bg_v;
+
+ enum mode_t this_mode;
+ static Bool rv_p;
+
+ XGCValues gcv;
+
+ XGetWindowAttributes (dpy, window, &xgwa);
+ cmap = xgwa.colormap;
+
+ if (!ncolors)
+ {
+ char *mode_str = get_string_resource ("mode", "Mode");
+ rv_p = get_boolean_resource ("reverseVideo", "ReverseVideo");
+ cycle_p = get_boolean_resource ("cycle", "Cycle");
+ ncolors = get_integer_resource ("ncolors", "Integer");
+ delay = get_integer_resource ("delay", "Integer");
+ cycle_delay = get_integer_resource ("cycleDelay", "Integer");
+ iterations = get_integer_resource ("iterations", "Integer");
+ if (iterations < 0) iterations = 0;
+ else if (iterations > 7) iterations = 7;
+
+ if (ncolors <= 2) ncolors = 0;
+ if (ncolors == 0) mono_p = True;
+
+ fg_pixel = get_pixel_resource ("background", "Background", dpy, cmap);
+ bg_pixel = get_pixel_resource ("foreground", "Foreground", dpy, cmap);
+
+ if (fg_pixel == bg_pixel)
+ {
+ XColor black, white;
+ black.red = black.green = black.blue = 0;
+ white.red = white.green = white.blue = 0xFFFF;
+ black.flags = white.flags = DoRed|DoGreen|DoBlue;
+ XAllocColor(dpy, cmap, &black);
+ XAllocColor(dpy, cmap, &white);
+ if (bg_pixel == black.pixel)
+ fg_pixel = white.pixel;
+ else
+ fg_pixel = black.pixel;
+ }
+
+ if (mono_p) cycle_p = False;
+
+ gcv.foreground = fg_pixel;
+ gcv.background = bg_pixel;
+ gc = XCreateGC (dpy, window, GCForeground|GCBackground, &gcv);
+ gcv.foreground = bg_pixel;
+ gc2 = XCreateGC (dpy, window, GCForeground, &gcv);
+
+ if (!mode_str || !strcmp (mode_str, "random"))
+ mode = MODE_RANDOM;
+ else if (!strcmp (mode_str, "h") || !strcmp (mode_str, "hue"))
+ mode = MODE_H;
+ else if (!strcmp (mode_str, "s") || !strcmp (mode_str, "saturation"))
+ mode = MODE_S;
+ else if (!strcmp (mode_str, "v") || !strcmp (mode_str, "value"))
+ mode = MODE_V;
+ else
+ {
+ fprintf (stderr,
+ "%s: mode must be hue, saturation, value, or random, not \"%s\"\n",
+ progname, mode_str);
+ mode = MODE_RANDOM;
+ }
+ }
+
+ this_mode = mode;
+ if (!mono_p && mode == MODE_RANDOM)
+ switch (random () % 6) {
+ case 0: this_mode = MODE_H; break;
+ case 1: this_mode = MODE_S; break;
+ case 2: this_mode = MODE_V; break;
+ default: break;
+ }
+
+ if (mono_p)
+ extra_krinkly_p = !(random() % 15);
+ else
+ extra_krinkly_p = !(random() % 5);
+
+ if (!mono_p)
+ {
+ double distance, fg_H, bg_H, dh;
+
+ RETRY:
+ fg_h = random() % 360;
+ fg_s = frand(1.0);
+ fg_v = frand(1.0);
+
+ bg_h = fg_h;
+ bg_s = fg_s;
+ bg_v = fg_v;
+
+ switch (this_mode)
+ {
+ case MODE_H:
+ bg_h = random() % 360;
+ if (fg_v < 0.4)
+ goto RETRY;
+ distance = fg_h - bg_h;
+ if (distance < 0)
+ distance = -distance;
+ if (distance > 360)
+ distance = 180 - (distance - 180);
+ if (distance < 30)
+ goto RETRY;
+ break;
+
+ case MODE_S:
+ bg_s = frand(1.0);
+ if (fg_v < 0.4)
+ goto RETRY;
+ distance = fg_s - bg_s;
+ if (distance < 0)
+ distance = -distance;
+ if (distance < 0.2)
+ goto RETRY;
+ break;
+
+ case MODE_V:
+ bg_v = frand(1.0);
+ distance = fg_v - bg_v;
+ if (distance < 0)
+ distance = -distance;
+ if (distance < 0.4)
+ goto RETRY;
+ break;
+
+ default:
+ bg_h = random() % 360;
+ bg_s = frand(1.0);
+ bg_v = frand(1.0);
+
+ fg_H = ((double) fg_h) / 360;
+ bg_H = ((double) bg_h) / 360;
+ dh = fg_H - bg_H;
+ if (dh < 0) dh = -dh;
+ if (dh > 0.5) dh = 0.5 - (dh - 0.5);
+ distance = sqrt ((dh * dh) +
+ ((fg_s - bg_s) * (fg_s - bg_s)) +
+ ((fg_v - bg_v) * (fg_v - bg_v)));
+ if (distance < 0.2)
+ goto RETRY;
+ }
+
+ cycle_p = True;
+ if (colors)
+ free_colors (dpy, cmap, colors, ncolors);
+ else
+ colors = (XColor *) malloc (ncolors * sizeof(*colors));
+
+ cycle_direction = (random() & 1 ? 1 : -1);
+
+ RETRY_NON_WRITABLE:
+ {
+ int n = ncolors;
+ make_color_ramp (dpy, cmap,
+ fg_h, fg_s, fg_v,
+ bg_h, bg_s, bg_v,
+ colors, &n,
+ True, True, cycle_p);
+ if (n == 0 && cycle_p)
+ {
+ cycle_p = False;
+ goto RETRY_NON_WRITABLE;
+ }
+ ncolors = n;
+ }
+
+ if (ncolors <= 0)
+ mono_p = 1;
+ }
+
+ if (mono_p)
+ {
+ static Bool done = False;
+ static XColor c[50];
+ colors = c;
+ cycle_p = False;
+ ncolors = sizeof(c)/sizeof(*c);
+ if (!done)
+ {
+ int i;
+ done = True;
+ colors[0].pixel = fg_pixel;
+ for (i = 1; i < ncolors; i++)
+ colors[i].pixel = bg_pixel;
+ }
+ }
+
+ XSetForeground (dpy, gc, colors[1].pixel);
+ XFillRectangle (dpy, window, gc, 0, 0, xgwa.width, xgwa.height);
+}
+
+
+#define HEIGHT_TO_PIXEL(height) \
+ ((height) < 0 \
+ ? (extra_krinkly_p \
+ ? ncolors - ((-(height)) % ncolors) \
+ : 0) \
+ : ((height) >= ncolors \
+ ? (extra_krinkly_p \
+ ? (height) % ncolors \
+ : ncolors-1) \
+ : (height)))
+
+
+static unsigned int
+set (unsigned int l,
+ unsigned int c,
+ unsigned int size,
+ int height)
+{
+ int rang = 1 << (NSTEPS - size);
+ height = height + (random () % rang) - rang / 2;
+ height = HEIGHT_TO_PIXEL(height);
+ CELL (l, c) = height;
+ return colors[height].pixel;
+}
+
+static void
+floyd_steinberg (Display *dpy, Window window)
+{
+ int x, y, err;
+
+ /* Instead of repeatedly calling XPutPixel(), we make an Image and then
+ send its bits over all at once. This consumes much less network
+ bandwidth. The image we create is Wx1 intead of WxH, so that we
+ don't use enormous amounts of memory.
+ */
+ XImage *image =
+ XCreateImage (dpy, xgwa.visual,
+ 1, XYBitmap, 0, /* depth, format, offset */
+ (char *) calloc ((xmax + 8) / 8, 1), /* data */
+ xmax, 1, 8, 0); /* w, h, pad, bpl */
+
+ XSetForeground (dpy, gc, colors[0].pixel);
+ XSetBackground (dpy, gc, colors[1].pixel);
+
+ for (y = 0; y < ymax - 1; y++)
+ {
+ for (x = 0; x < xmax - 1; x++)
+ {
+ if (CELL(x, y) < 0)
+ {
+ err = CELL (x, y);
+ XPutPixel (image, x, 0, 1);
+ }
+ else
+ {
+ err = CELL (x, y) - 1;
+ XPutPixel (image, x, 0, 0);
+ }
+ /* distribute error */
+ CELL (x, y+1) += (int) (((float) err) * 3.0/8.0);
+ CELL (x+1, y) += (int) (((float) err) * 3.0/8.0);
+ CELL (x+1, y+1) += (int) (((float) err) * 1.0/4.0);
+ }
+ XPutImage (dpy, window, gc, image, 0, 0, 0, y, xmax, 1);
+ }
+ XDestroyImage (image);
+}
+
+static void
+draw (Display *dpy, Window window,
+ int x, int y, unsigned long pixel, int grid_size)
+{
+ static unsigned int last_pixel, last_valid = 0;
+ if (! (last_valid && pixel == last_pixel))
+ XSetForeground (dpy, gc, pixel);
+ last_valid = 1, last_pixel = pixel;
+ if (grid_size == 1)
+ XDrawPoint (dpy, window, gc, x, y);
+ else
+ XFillRectangle (dpy, window, gc, x, y, grid_size, grid_size);
+}
+
+
+static void
+draw_map (Display *dpy, Window window)
+{
+ int xstep, ystep, xnextStep, ynextStep;
+ int x, y, i, x1, x2, y1, y2;
+ unsigned int pixel, qpixels [4];
+
+ int backwards = random() & 1;
+
+ xmax = xgwa.width;
+ ymax = xgwa.height;
+
+ cell = (signed char *) calloc (xmax * ymax, 1);
+ if (cell == NULL)
+ exit (1);
+
+ CELL (0, 0) = 0;
+ xstep = (backwards ? -COUNT : COUNT);
+ ystep = COUNT;
+ for (i = 0; i < iterations; i++)
+ {
+ xnextStep = xstep / 2;
+ ynextStep = ystep / 2;
+ for (x = (backwards ? xmax-1 : 0);
+ (backwards ? x >= 0 : x < xmax);
+ x += xstep)
+ {
+ x1 = x + xnextStep;
+ if (x1 < 0)
+ x1 = xmax-1;
+ else if (x1 >= xmax)
+ x1 = 0;
+
+ x2 = x + xstep;
+ if (x2 < 0)
+ x2 = xmax-1;
+ else if (x2 >= xmax)
+ x2 = 0;
+
+ for (y = 0; y < ymax; y += ystep)
+ {
+ y1 = y + ynextStep;
+ if (y1 < 0)
+ y1 = ymax-1;
+ else if (y1 >= ymax)
+ y1 = 0;
+
+ y2 = y + ystep;
+ if (y2 < 0)
+ y2 = ymax-1;
+ else if (y2 >= ymax)
+ y2 = 0;
+
+ qpixels [0] = colors [HEIGHT_TO_PIXEL (CELL (x, y))].pixel;
+ qpixels [1] = colors [HEIGHT_TO_PIXEL (CELL (x, y2))].pixel;
+ qpixels [2] = colors [HEIGHT_TO_PIXEL (CELL (x2, y))].pixel;
+ qpixels [3] = colors [HEIGHT_TO_PIXEL (CELL (x2, y2))].pixel;
+
+ pixel = set (x, y1, i,
+ ((int) CELL (x, y) + (int) CELL (x, y2) + 1) / 2);
+ if (! mono_p &&
+ (pixel != qpixels[0] || pixel != qpixels[1] ||
+ pixel != qpixels[2] || pixel != qpixels[3]))
+ draw (dpy, window, x, y1, pixel, ynextStep);
+
+ pixel = set (x1, y, i,
+ ((int) CELL (x, y) + (int) CELL (x2, y) + 1) / 2);
+ if (! mono_p &&
+ (pixel != qpixels[0] || pixel != qpixels[1] ||
+ pixel != qpixels[2] || pixel != qpixels[3]))
+ draw (dpy, window, x1, y, pixel, ynextStep);
+
+ pixel = set (x1, y1, i,
+ ((int) CELL (x, y) + (int) CELL (x, y2) +
+ (int) CELL (x2, y) + (int) CELL (x2, y2) + 2)
+ / 4);
+ if (! mono_p &&
+ (pixel != qpixels[0] || pixel != qpixels[1] ||
+ pixel != qpixels[2] || pixel != qpixels[3]))
+ draw (dpy, window, x1, y1, pixel, ynextStep);
+
+
+ if (cycle_p)
+ {
+ struct timeval now;
+ static struct timeval then = { 0, };
+ unsigned long diff;
+#ifdef GETTIMEOFDAY_TWO_ARGS
+ struct timezone tzp;
+ gettimeofday(&now, &tzp);
+#else
+ gettimeofday(&now);
+#endif
+ diff = (((now.tv_sec - then.tv_sec) * 1000000) +
+ (now.tv_usec - then.tv_usec));
+ if (diff > cycle_delay)
+ {
+ rotate_colors (dpy, cmap, colors, ncolors,
+ cycle_direction);
+ then = now;
+ }
+ }
+ }
+ }
+ xstep = xnextStep;
+ ystep = ynextStep;
+ if (!mono_p)
+ XSync (dpy, True);
+ }
+ if (mono_p)
+ /* in mono-mode, we do all the drawing at the end */
+ floyd_steinberg (dpy, window);
+
+ free (cell);
+ XSync (dpy, True);
+}
+
+
+char *progclass = "Imsmap";
+
+char *defaults [] = {
+ "Imsmap.background: black", /* to placate SGI */
+ "Imsmap.foreground: black",
+ "*mode: random",
+ "*ncolors: 50",
+ "*iterations: 7",
+ "*delay: 10",
+ "*cycleDelay: 100000",
+ "*cycle: true",
+ 0
+};
+
+XrmOptionDescRec options [] = {
+ { "-ncolors", ".ncolors", XrmoptionSepArg, 0 },
+ { "-delay", ".delay", XrmoptionSepArg, 0 },
+ { "-cycle-delay", ".cycleDelay", XrmoptionSepArg, 0 },
+ { "-mode", ".mode", XrmoptionSepArg, 0 },
+ { "-iterations", ".iterations", XrmoptionSepArg, 0 },
+ { "-cycle", ".cycle", XrmoptionNoArg, "True" },
+ { "-no-cycle", ".cycle", XrmoptionNoArg, "False" },
+ { 0, 0, 0, 0 }
+};
+
+
+void
+screenhack (Display *dpy, Window window)
+{
+ while (1)
+ {
+ init_map (dpy, window);
+ draw_map (dpy, window);
+ if (delay)
+ {
+ if (cycle_p)
+ {
+ time_t start = time((time_t) 0);
+ while (start + delay > time((time_t) 0))
+ {
+ rotate_colors (dpy, cmap, colors, ncolors,
+ cycle_direction);
+ if (cycle_delay) usleep(cycle_delay);
+ }
+ }
+ else
+ sleep (delay);
+ }
+ }
+}
projects / xscreensaver / blobdiff