/* xscreensaver, Copyright (c) 1993, 1995, 1996, 1998 * Jamie Zawinski * * 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. */ /* This file was ported from xlock for use in xscreensaver (and standalone) * by jwz on 18-Oct-93. (And again, 11-May-97.) Original copyright reads: * * static char sccsid[] = "@(#)flame.c 1.4 91/09/27 XLOCK"; * * flame.c - recursive fractal cosmic flames. * * Copyright (c) 1991 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. * * Comments and additions should be sent to the author: * * naughton@eng.sun.com * * Patrick J. Naughton * MS 21-14 * Sun Laboritories, Inc. * 2550 Garcia Ave * Mountain View, CA 94043 * * Revision History: * 01-Jun-95: This should look more like the original with some updates by * Scott Draves. * 27-Jun-91: vary number of functions used. * 24-Jun-91: fixed portability problem with integer mod (%). * 06-Jun-91: Written. (received from Scott Draves, spot@cs.cmu.edu). */ #include #include "screenhack.h" #include /* so we can ignore SIGFPE */ #define POINT_BUFFER_SIZE 10 #define MAXLEV 4 #define MAXKINDS 10 static double f[2][3][MAXLEV]; /* three non-homogeneous transforms */ static int max_total; static int max_levels; static int max_points; static int cur_level; static int variation; static int snum; static int anum; static int num_points; static int total_points; static int pixcol; static int ncolors; static XColor *colors; static XPoint points [POINT_BUFFER_SIZE]; static GC gc; static int delay, delay2; static int width, height; static short halfrandom (int mv) { static short lasthalf = 0; unsigned long r; if (lasthalf) { r = lasthalf; lasthalf = 0; } else { r = random (); lasthalf = r >> 16; } return (r % mv); } static void init_flame (Display *dpy, Window window) { XGCValues gcv; XWindowAttributes xgwa; Colormap cmap; #if defined(SIGFPE) && defined(SIG_IGN) /* No doubt a better fix would be to track down where the NaN is coming from, and code around that; but this should do. Apparently most systems (Linux, Solaris, Irix, ...) ignore FPE by default -- but FreeBSD dumps core by default. */ signal (SIGFPE, SIG_IGN); #endif XGetWindowAttributes (dpy, window, &xgwa); width = xgwa.width; height = xgwa.height; cmap = xgwa.colormap; max_points = get_integer_resource ("iterations", "Integer"); if (max_points <= 0) max_points = 100; max_levels = max_points; max_total = get_integer_resource ("points", "Integer"); if (max_total <= 0) max_total = 10000; delay = get_integer_resource ("delay", "Integer"); if (delay < 0) delay = 0; delay2 = get_integer_resource ("delay2", "Integer"); if (delay2 < 0) delay2 = 0; variation = random() % MAXKINDS; if (mono_p) ncolors = 0; else { ncolors = get_integer_resource ("colors", "Integer"); if (ncolors <= 0) ncolors = 128; colors = (XColor *) malloc ((ncolors+1) * sizeof (*colors)); make_smooth_colormap (dpy, xgwa.visual, xgwa.colormap, colors, &ncolors, True, 0, True); if (ncolors <= 2) mono_p = True, ncolors = 0; } gcv.foreground = get_pixel_resource ("foreground", "Foreground", dpy, cmap); gcv.background = get_pixel_resource ("background", "Background", dpy, cmap); if (! mono_p) { pixcol = halfrandom (ncolors); gcv.foreground = (colors [pixcol].pixel); } gc = XCreateGC (dpy, window, GCForeground | GCBackground, &gcv); } static int recurse (double x, double y, int l, Display *dpy, Window win) { int xp, yp, i; double nx, ny; if (l == max_levels) { total_points++; if (total_points > max_total) /* how long each fractal runs */ return 0; if (x > -1.0 && x < 1.0 && y > -1.0 && y < 1.0) { xp = points[num_points].x = (int) ((width / 2) * (x + 1.0)); yp = points[num_points].y = (int) ((height / 2) * (y + 1.0)); num_points++; if (num_points >= POINT_BUFFER_SIZE) { XDrawPoints (dpy, win, gc, points, num_points, CoordModeOrigin); num_points = 0; /* if (delay) usleep (delay); */ /* XSync (dpy, False); */ } } } else { for (i = 0; i < snum; i++) { /* Scale back when values get very large. Spot sez: "I think this happens on HPUX. I think it's non-IEEE to generate an exception instead of a silent NaN." */ if ((abs(x) > 1.0E5) || (abs(y) > 1.0E5)) x = x / y; nx = f[0][0][i] * x + f[0][1][i] * y + f[0][2][i]; ny = f[1][0][i] * x + f[1][1][i] * y + f[1][2][i]; if (i < anum) { switch (variation) { case 0: /* sinusoidal */ nx = sin(nx); ny = sin(ny); break; case 1: /* complex */ { double r2 = nx * nx + ny * ny + 1e-6; nx = nx / r2; ny = ny / r2; } break; case 2: /* bent */ if (nx < 0.0) nx = nx * 2.0; if (ny < 0.0) ny = ny / 2.0; break; case 3: /* swirl */ { double r = (nx * nx + ny * ny); /* times k here is fun */ double c1 = sin(r); double c2 = cos(r); double t = nx; if (nx > 1e4 || nx < -1e4 || ny > 1e4 || ny < -1e4) ny = 1e4; else ny = c2 * t + c1 * ny; nx = c1 * nx - c2 * ny; } break; case 4: /* horseshoe */ { double r, c1, c2, t; /* Avoid atan2: DOMAIN error message */ if (nx == 0.0 && ny == 0.0) r = 0.0; else r = atan2(nx, ny); /* times k here is fun */ c1 = sin(r); c2 = cos(r); t = nx; nx = c1 * nx - c2 * ny; ny = c2 * t + c1 * ny; } break; case 5: /* drape */ { double t; /* Avoid atan2: DOMAIN error message */ if (nx == 0.0 && ny == 0.0) t = 0.0; else t = atan2(nx, ny) / M_PI; if (nx > 1e4 || nx < -1e4 || ny > 1e4 || ny < -1e4) ny = 1e4; else ny = sqrt(nx * nx + ny * ny) - 1.0; nx = t; } break; case 6: /* broken */ if (nx > 1.0) nx = nx - 1.0; if (nx < -1.0) nx = nx + 1.0; if (ny > 1.0) ny = ny - 1.0; if (ny < -1.0) ny = ny + 1.0; break; case 7: /* spherical */ { double r = 0.5 + sqrt(nx * nx + ny * ny + 1e-6); nx = nx / r; ny = ny / r; } break; case 8: /* */ nx = atan(nx) / M_PI_2; ny = atan(ny) / M_PI_2; break; /* #if 0 */ /* core dumps on some machines, why not all? */ case 9: /* complex sine */ { double u = nx; double v = ny; double ev = exp(v); double emv = exp(-v); nx = (ev + emv) * sin(u) / 2.0; ny = (ev - emv) * cos(u) / 2.0; } break; case 10: /* polynomial */ if (nx < 0) nx = -nx * nx; else nx = nx * nx; if (ny < 0) ny = -ny * ny; else ny = ny * ny; break; /* #endif */ default: nx = sin(nx); ny = sin(ny); } } if (!recurse (nx, ny, l + 1, dpy, win)) return 0; } } return 1; } static void flame (Display *dpy, Window window) { int i, j, k; static int alt = 0; if (!(cur_level++ % max_levels)) { if (delay2) usleep (delay2); XClearWindow (dpy, window); alt = !alt; variation = random() % MAXKINDS; } else { if (ncolors > 2) { XSetForeground (dpy, gc, colors [pixcol].pixel); if (--pixcol < 0) pixcol = ncolors - 1; } } /* number of functions */ snum = 2 + (cur_level % (MAXLEV - 1)); /* how many of them are of alternate form */ if (alt) anum = 0; else anum = halfrandom (snum) + 2; /* 6 coefs per function */ for (k = 0; k < snum; k++) { for (i = 0; i < 2; i++) for (j = 0; j < 3; j++) f[i][j][k] = ((double) (random() & 1023) / 512.0 - 1.0); } num_points = 0; total_points = 0; (void) recurse (0.0, 0.0, 0, dpy, window); XDrawPoints (dpy, window, gc, points, num_points, CoordModeOrigin); XSync (dpy, False); if (delay) usleep (delay); } #if defined(__hpux) && defined(PLOSS) /* I don't understand why this is necessary, but I'm told that this program does nothing at all on HP-sUX without it. I'm further told that HPUX 11.0 doesn't define PLOSS, and works ok without this section. Go figure. */ #undef random #undef srandom #include int matherr(x) register struct exception *x; { if (x->type == PLOSS) return 1; else return 0; } #endif /* __hpux */ char *progclass = "Flame"; char *defaults [] = { ".background: black", ".foreground: white", "*colors: 64", "*iterations: 25", "*delay: 50000", "*delay2: 2000000", "*points: 10000", 0 }; XrmOptionDescRec options [] = { { "-colors", ".colors", XrmoptionSepArg, 0 }, { "-iterations", ".iterations", XrmoptionSepArg, 0 }, { "-delay", ".delay", XrmoptionSepArg, 0 }, { "-delay2", ".delay2", XrmoptionSepArg, 0 }, { "-points", ".points", XrmoptionSepArg, 0 }, { 0, 0, 0, 0 } }; void screenhack (Display *dpy, Window window) { init_flame (dpy, window); while (1) { flame (dpy, window); screenhack_handle_events (dpy); } }