#include <bitmapfonts.c>

WINMAIN
{
	int n,i; char str[100];
	GRAPHICS(1024,768,"Nonlinear things [Stephen Brooks 2004]");
	loadfont("font.dat","normal");
	double zoom=yres/2,k=1;
	LOOP
	{
		if (mb&1) zoom*=1.01; if (mb&2) zoom/=1.01;
		if (KEY(VK_Z)) k*=1.01; if (KEY(VK_X)) k/=1.01;
		double th=fmod(M_TWOPI*mx/xres+eithertime()*0.01,M_TWOPI),cth=cos(th),sth=sin(th);
		double ox,x,y;
		for (n=0;n<100;n++)
		{
			x=0.01*n; y=0;
			for (i=4000;i>0 && x*x+y*y<100;i--)
			{
				putpix(xres/2+x*zoom,yres/2+y*zoom,50+n);
				ox=x; x=x*cth+y*sth;
				y=y*cth-ox*sth+k*x*x;
			}
		}
		sprintf(str,"Fractional tune = %.5lf",th/M_TWOPI);
		bfwrite(0,0,str,15);
		ccl(0);
	}
}