#include <xsimple.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>

#define WIN_X 110
#define WIN_Y 75
#define WIN_W 800
#define WIN_H 600

#define COUNT 100000
#define SCALE 60
#define XOFF 0
#define YOFF 0

#define BGCOLOR BLACK
#define FGCOLOR GREEN

unsigned long bgcolor, fgcolor;

double scale = SCALE;
int xoff = XOFF, yoff = YOFF;

XImage *img;
int pad;


static void draw()
{
    static double x, y;
    double r;
    double a, b, c, d, e, f;
    double newx, newy;
    int sx, sy;

    r = (double)rand() / (double)RAND_MAX;
    if (r <= .01) {
	a = 0.; b = 0.; c = 0.; d = .16; e = 0.; f = 0.;
    } else if (r > .01 && r <= .86) {
	a = .85; b = .04; c = -.04; d = .85; e = 0.; f = 1.6;
    } else if (r > .86 && r <= .93) {
	a = .2; b = -.26; c = .23; d = .22; e = 0.; f = 1.6;
    } else {
	a = -.15; b = .28; c = .26; d = .24; e = 0.; f = .44;
    }

    newx = (a * x) + (b * y) + e;
    newy = (c * x) + (d * y) + f;
    x = newx; y = newy;

    sx = (int)(x * scale) + (WIN_W / 2) + xoff;
    sy = (WIN_H - 1) - ((int)(y * scale) - yoff);
    psetximage(img, sx, sy, FGCOLOR);
}

static void init()
{
    xinit("ifsfern", "Ifsfern", "IFS Fern", WIN_X, WIN_Y, WIN_W, WIN_H, 0,
	    "black", "black", 0);
    img = mkximage(WIN_W, WIN_H, xv.depth, &pad);
    cls(BGCOLOR);
    update(0, 0, 0, 0);
    srand(time(NULL));
}

int main(int argc, char **argv)
{
    int i, count = COUNT;

    if (argc > 1) {
	if (argc < 5) {
	    fprintf(stderr, "usage: ifsfern [count scale xoff yoff]\n");
	    exit(1);
	}
	count = atoi(argv[1]);
	scale = atof(argv[2]);
	xoff = atoi(argv[3]);
	yoff = atoi(argv[4]);
    }

    init();

    for (i = 0; i < count; i++)
	draw();

    putximage(img, 0, 0, 0, 0, WIN_W, WIN_H);
    update(0, 0, 0, 0);

    for (;;) {
	XEvent e;

	while (getevent(&e)) {
	    switch (e.type) {
		case Expose:
		    doexpose(&e);
		    break;
		case KeyPress:
		    if (XLookupKeysym((XKeyEvent *)&e, 0) == XK_q)
			exit(0);
		    break;
	    }
	}
	usleep(1000);
    }
}
.