--- /dev/null
+/* squiral, by "Jeff Epler" <jepler@inetnebr.com>, 18-mar-1999.
+ *
+ * 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 "screenhack.h"
+#include "colors.h"
+#include "erase.h"
+#include "yarandom.h"
+
+#define R(x) (abs(random())%x)
+#define PROB(x) (abs(random())<(x*(double)RAND_MAX))
+
+#define NCOLORSMAX 255
+static int width, height, count, cycle;
+static double frac, disorder, handedness;
+static int ncolors=0;
+static GC draw_gc, erase_gc;
+static XColor colors[NCOLORSMAX];
+#define STATES 8
+
+/* 0- 3 left-winding */
+/* 4- 7 right-winding */
+
+#define CLEAR1(x,y) (!fill[((y)%height)*width+(x)%width])
+#define MOVE1(x,y) (fill[((y)%height)*width+(x)%width]=1, XDrawPoint(dpy, window, draw_gc, (x)%width,(y)%height), cov++)
+
+static int cov;
+static int dirh[4];
+static int dirv[4];
+
+static int *fill;
+
+#define CLEARDXY(x,y,dx,dy) CLEAR1(x+dx, y+dy) && CLEAR1(x+dx+dx, y+dy+dy)
+#define MOVEDXY(x,y,dx,dy) MOVE1 (x+dx, y+dy), MOVE1 (x+dx+dx, y+dy+dy)
+
+#define CLEAR(d) CLEARDXY(w->h,w->v, dirh[d],dirv[d])
+#define MOVE(d) (XSetForeground(dpy, draw_gc, colors[w->c].pixel), \
+ MOVEDXY(w->h,w->v, dirh[d],dirv[d]), \
+ w->h=w->h+dirh[d]*2, \
+ w->v=w->v+dirv[d]*2, dir=d)
+
+#define RANDOM (void) (w->h = R(width), w->v = R(height), w->c = R(ncolors), \
+ type=R(2), dir=R(4), (cycle && (w->cc=R(3)+ncolors)))
+
+struct worm {
+ int h;
+ int v;
+ int s;
+ int c;
+ int cc;
+} *worms;
+
+#define SUCC(x) ((x+1)%4)
+#define PRED(x) ((x+3)%4)
+#define CCW PRED(dir)
+#define CW SUCC(dir)
+#define REV ((dir+2)%4)
+#define STR (dir)
+#define TRY(x) if (CLEAR(x)) { MOVE(x); break; }
+
+static void
+do_worm(Display *dpy, Window window, struct worm *w)
+{
+ int type = w->s / 4;
+ int dir = w->s % 4;
+
+ w->c = (w->c+w->cc) % ncolors;
+
+ if (PROB(disorder)) type=PROB(handedness);
+ switch(type) {
+ case 0: /* CCW */
+ TRY(CCW)
+ TRY(STR)
+ TRY(CW)
+ RANDOM;
+ break;
+ case 1: /* CW */
+ TRY(CW)
+ TRY(STR)
+ TRY(CCW)
+ RANDOM;
+ break;
+ }
+ w->s = type*4+dir;
+ w->h = w->h % width;
+ w->v = w->v % height;
+}
+
+static void
+init_squiral(Display *dpy, Window window)
+{
+ XGCValues gcv;
+ Colormap cmap;
+ XWindowAttributes xgwa;
+ Bool writeable = False;
+ int i;
+
+ XClearWindow(dpy, window);
+ XGetWindowAttributes(dpy, window, &xgwa);
+ width = xgwa.width;
+ height = xgwa.height;
+
+ cmap = xgwa.colormap;
+ gcv.foreground = get_pixel_resource("foreground",
+ "Foreground", dpy, cmap);
+ draw_gc = XCreateGC(dpy, window, GCForeground, &gcv);
+ gcv.foreground = get_pixel_resource ("background", "Background",dpy, cmap);
+ erase_gc = XCreateGC (dpy, window, GCForeground, &gcv);
+ cmap = xgwa.colormap;
+ if( ncolors ) {
+ free_colors(dpy, cmap, colors, ncolors);
+ ncolors = 0;
+ }
+ if( mono_p ) {
+ ncolors=1;
+ colors[0].pixel=get_pixel_resource("foreground","Foreground", dpy, cmap);
+ } else {
+ ncolors = get_integer_resource("ncolors", "Integer");
+ if (ncolors < 0 || ncolors > NCOLORSMAX)
+ ncolors = NCOLORSMAX;
+ make_uniform_colormap(dpy, xgwa.visual, cmap, colors, &ncolors, True,
+ &writeable, False);
+ if (ncolors <= 0) {
+ ncolors = 1;
+ colors[0].pixel=get_pixel_resource("foreground","Foreground",dpy, cmap);
+ }
+ }
+ count= get_integer_resource("count", "Integer");
+ frac = get_integer_resource("fill", "Integer")*0.01;
+ cycle= get_boolean_resource("cycle", "Cycle");
+ disorder=get_float_resource("disorder", "Float");
+ handedness=get_float_resource("handedness", "Float");
+
+ if(frac<0.01) frac=0.01;
+ if(frac>0.99) frac=0.99;
+ if(count==0) count=width/32;
+ if(count<1) count=1;
+ if(count>1000) count=1000;
+
+ if(worms) free(worms);
+ if(fill) free(fill);
+
+ worms=calloc(count, sizeof(struct worm));
+ fill=calloc(width*height, sizeof(int));
+
+ dirh[0]=0; dirh[1]=1; dirh[2]=0; dirh[3]=width-1;
+ dirv[0]=height-1; dirv[1]=0; dirv[2]=1; dirv[3]=0;
+ for(i=0;i<count;i++) {
+ worms[i].h=R(width);
+ worms[i].v=R(height);
+ worms[i].s=R(4)+4*PROB(handedness);
+ worms[i].c=R(ncolors);
+ if(cycle) { worms[i].cc=R(3)+ncolors; }
+ else worms[i].cc=0;
+ }
+}
+
+void
+screenhack(Display *dpy, Window window)
+{
+ int inclear, i;
+ int delay= get_integer_resource("delay", "Integer");
+ init_squiral(dpy, window);
+ cov=0; inclear=height;
+ while(1) {
+ if(inclear<height) {
+ XDrawLine(dpy, window, erase_gc, 0, inclear, width-1, inclear);
+ memset(&fill[inclear*width], 0, sizeof(int)*width);
+ XDrawLine(dpy, window, erase_gc, 0, height-inclear-1, width-1,
+ height-inclear-1);
+ memset(&fill[(height-inclear-1)*width], 0, sizeof(int)*width);
+ inclear++;
+ XDrawLine(dpy, window, erase_gc, 0, inclear, width-1, inclear);
+ memset(&fill[inclear*width], 0, sizeof(int)*width);
+ XDrawLine(dpy, window, erase_gc, 0, height-inclear-1, width-1,
+ height-inclear-1);
+ memset(&fill[(height-inclear-1)*width], 0, sizeof(int)*width);
+ inclear++;
+ if(inclear>height/2) inclear=height;
+ }
+ else if(cov>(frac*width*height)) {
+ inclear=0;
+ cov=0;
+ }
+ for(i=0;i<count;i++) do_worm(dpy, window, &worms[i]);
+ screenhack_handle_events(dpy);
+ usleep(delay);
+ }
+}
+
+char *progclass="Squiral";
+
+char *defaults[] = {
+ ".background: black",
+ ".foreground: white",
+ "*fill: 75",
+ "*count: 0",
+ "*ncolors: 100",
+ "*delay: 1000",
+ "*disorder: 0.005",
+ "*cycle: False",
+ "*handedness: .5",
+ 0
+};
+
+XrmOptionDescRec options[] = {
+ {"-fill", ".fill", XrmoptionSepArg, 0},
+ {"-count", ".count", XrmoptionSepArg, 0},
+ {"-delay", ".delay", XrmoptionSepArg, 0},
+ {"-disorder", ".disorder", XrmoptionSepArg, 0},
+ {"-handedness", ".handedness", XrmoptionSepArg, 0},
+ {"-ncolors", ".ncolors", XrmoptionSepArg, 0},
+ {"-cycle", ".cycle", XrmoptionNoArg, "True"},
+ {"-no-cycle", ".cycle", XrmoptionNoArg, "False"},
+};
projects / xscreensaver / blobdiff