ball moving on a sphere

#include
#include
#include
#include
#define pi 3.14285
#define round(a)((int)(a+0.5))
int i;
void parcircle(int ,int ,float,int ) ;
void parcir(int xc,int yc,float r,int sang,int eang,int col)
{ int k;
float x,y;

for(k=sang;k { x=xc+r*cos(pi*k/180);
y=yc+r*sin(pi*k/180);
putpixel(round(x),round(y),col);
}
}

void drawcir(int x,int y,float r,int sang)
{ int k=0;
int eang;
eang=sang+120;
while(k!=3)
{
parcir(x,y,r,sang,eang,(k+1));
sang=eang;
eang+=120;
k++;
}
}
void parc(int xc,int yc,float r1,int i)
{ int k=0,r; float x,y;
r=r1+20;
for(k=0;k<360;k++)
{ x=xc+r*cos(pi*k/180);
y=yc+r*sin(pi*k/180);

cleardevice();
parcircle(xc,yc,r1,11);
i+=5;
drawcir(round(x),round(y),20,i);

}

}
void parcircle(int xc,int yc,float r,int col)
{ int k=0; float x,y;
for(k=0;k<360;k++)
{ x=xc+r*cos(pi*k/180);
y=yc+r*sin(pi*k/180);
putpixel(round(x),round(y),col);

}
}
//========================
void main()
{ int gd,gm;
detectgraph(&gd,&gm);
int x,y,xc,yc; float r,r1;
i=0;

initgraph(&gd,&gm,"..\\bgi");

printf("\n enter the centre");
scanf("%d",&x);
scanf("%d",&y);
printf("\n enter the radius");
scanf("%f",&r);
xc=x;yc=y;

while(!kbhit())
{

parc(xc,yc,r,i);


}

}