129.飘带图案

/* linesin */
#include <graphics.h>
#include <math.h>
#define PI 3.1415926
void main()
{
  double a;
  int x1,y1,x2,px=320,py=240;
  int gdriver=DETECT,gmode;
  initgraph(&gdriver,&gmode,"c:\\tc");
  cleardevice();
  setcolor(4);
  outtextxy(80,20,"This program show the Linesin picture.");
  for(a=0;a<=PI;a+=PI/380)
  {
    x1=px+280*cos(1.6*a);
    y1=479-((90*sin(8*a))*cos(a/2.5)+py);
    x2=py+280*cos(1.8*a);
    line(x1,y1,x2,y1);
  }
  outtextxy(80,460,"Press any key to quit...");
  getch();
  closegraph();
}