X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=hacks%2Fsierpinski.c;fp=hacks%2Fsierpinski.c;h=ca22999c147f0dd083ad443dbc5e3255b806277a;hb=df7adbee81405e2849728a24b498ad2117784b1f;hp=0000000000000000000000000000000000000000;hpb=41fae2ad67bc37e31c4d967bae81e4f3f50fa55a;p=xscreensaver diff --git a/hacks/sierpinski.c b/hacks/sierpinski.c new file mode 100644 index 00000000..ca22999c --- /dev/null +++ b/hacks/sierpinski.c @@ -0,0 +1,184 @@ +/* -*- Mode: C; tab-width: 4 -*- */ +/* sierpinski --- Sierpinski's triangle fractal */ + +#if !defined( lint ) && !defined( SABER ) +static const char sccsid[] = "@(#)sierpinski.c 4.05 97/09/19 xlockmore"; +#endif + +/* Copyright (c) 1996 by Desmond Daignault + * + * 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: + * 18-Sep-97: 3D version Antti Kuntsi . + * 20-May-97: Changed the name tri to sierpinski for more compatiblity + * 10-May-97: jwz@jwz.org: turned into a standalone program. + * 05-Sep-96: Desmond Daignault Datatimes Incorporated + * . + */ + +#ifdef STANDALONE +# define PROGCLASS "Sierpinski" +# define HACK_INIT init_sierpinski +# define HACK_DRAW draw_sierpinski +# define sierpinski_opts xlockmore_opts +# define DEFAULTS "*delay: 400000 \n" \ + "*count: 2000 \n" \ + "*cycles: 100 \n" \ + "*ncolors: 64 \n" +# define BRIGHT_COLORS +# include "xlockmore.h" /* from the xscreensaver distribution */ +#else /* !STANDALONE */ +# include "xlock.h" /* from the xlockmore distribution */ +#endif /* !STANDALONE */ + +ModeSpecOpt sierpinski_opts = +{0, NULL, 0, NULL, NULL}; + +#define MAXCORNERS 4 + +typedef struct { + int width, height; + int time; + int px, py; + int total_npoints; + int corners; + int npoints[MAXCORNERS]; + unsigned long colors[MAXCORNERS]; + XPoint *pointBuffer[MAXCORNERS]; + XPoint vertex[MAXCORNERS]; +} sierpinskistruct; + +static sierpinskistruct *tris = NULL; + +static void +startover(ModeInfo * mi) +{ + int j; + sierpinskistruct *sp = &tris[MI_SCREEN(mi)]; + + if (MI_NPIXELS(mi) > 2) { + if (sp->corners == 3) { + sp->colors[0] = (NRAND(MI_NPIXELS(mi))); + sp->colors[1] = (sp->colors[0] + MI_NPIXELS(mi) / 7 + + NRAND(2 * MI_NPIXELS(mi) / 7 + 1)) % MI_NPIXELS(mi); + sp->colors[2] = (sp->colors[0] + 4 * MI_NPIXELS(mi) / 7 + + NRAND(2 * MI_NPIXELS(mi) / 7 + 1)) % MI_NPIXELS(mi); + } else if (sp->corners == 4) { + sp->colors[0] = (NRAND(MI_NPIXELS(mi))); + sp->colors[1] = (sp->colors[0] + MI_NPIXELS(mi) / 7 + + NRAND(MI_NPIXELS(mi) / 7 + 1)) % MI_NPIXELS(mi); + sp->colors[2] = (sp->colors[0] + 3 * MI_NPIXELS(mi) / 7 + + NRAND(MI_NPIXELS(mi) / 7 + 1)) % MI_NPIXELS(mi); + sp->colors[3] = (sp->colors[0] + 5 * MI_NPIXELS(mi) / 7 + + NRAND(MI_NPIXELS(mi) / 7 + 1)) % MI_NPIXELS(mi); + } else { + (void) fprintf(stderr, "colors not set for %d corners\n", sp->corners); + } + } + for (j = 0; j < sp->corners; j++) { + sp->vertex[j].x = NRAND(sp->width); + sp->vertex[j].y = NRAND(sp->height); + } + sp->px = NRAND(sp->width); + sp->py = NRAND(sp->height); + sp->time = 0; + XClearWindow(MI_DISPLAY(mi), MI_WINDOW(mi)); +} + +void +init_sierpinski(ModeInfo * mi) +{ + sierpinskistruct *sp; + int i; + + if (tris == NULL) { + if ((tris = (sierpinskistruct *) calloc(MI_NUM_SCREENS(mi), + sizeof (sierpinskistruct))) == NULL) + return; + } + sp = &tris[MI_SCREEN(mi)]; + + sp->width = MI_WIN_WIDTH(mi); + sp->height = MI_WIN_HEIGHT(mi); + + sp->total_npoints = MI_BATCHCOUNT(mi); + if (sp->total_npoints < 1) + sp->total_npoints = 1; + sp->corners = MI_SIZE(mi); + if (sp->corners < 3 || sp->corners > 4) { + sp->corners = (LRAND() & 1) + 3; + } + for (i = 0; i < sp->corners; i++) { + if (!sp->pointBuffer[i]) + sp->pointBuffer[i] = (XPoint *) malloc(sp->total_npoints * + sizeof (XPoint)); + } + startover(mi); +} + +void +draw_sierpinski(ModeInfo * mi) +{ + Display *display = MI_DISPLAY(mi); + GC gc = MI_GC(mi); + sierpinskistruct *sp = &tris[MI_SCREEN(mi)]; + XPoint *xp[MAXCORNERS]; + int i = 0, v; + + if (MI_NPIXELS(mi) <= 2) + XSetForeground(display, gc, MI_WIN_WHITE_PIXEL(mi)); + for (i = 0; i < sp->corners; i++) + xp[i] = sp->pointBuffer[i]; + for (i = 0; i < sp->total_npoints; i++) { + v = NRAND(sp->corners); + sp->px = (sp->px + sp->vertex[v].x) / 2; + sp->py = (sp->py + sp->vertex[v].y) / 2; + xp[v]->x = sp->px; + xp[v]->y = sp->py; + xp[v]++; + sp->npoints[v]++; + } + for (i = 0; i < sp->corners; i++) { + if (MI_NPIXELS(mi) > 2) + XSetForeground(display, gc, MI_PIXEL(mi, sp->colors[i])); + XDrawPoints(display, MI_WINDOW(mi), gc, sp->pointBuffer[i], sp->npoints[i], + CoordModeOrigin); + sp->npoints[i] = 0; + } + if (++sp->time >= MI_CYCLES(mi)) + startover(mi); +} + +void +release_sierpinski(ModeInfo * mi) +{ + if (tris != NULL) { + int screen, i; + + for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++) { + for (i = 0; i < MAXCORNERS; i++) + if (tris[screen].pointBuffer[i] != NULL) { + (void) free((void *) tris[screen].pointBuffer[i]); + } + } + (void) free((void *) tris); + tris = NULL; + } +} + +void +refresh_sierpinski(ModeInfo * mi) +{ + /* Do nothing, it will refresh by itself */ +}