# Program to draw a Sphere using Ellipses

``` # include <iostream.h>
# include <graphics.h>
# include    <conio.h>
# include     <math.h>

# define  f                 0.3
# define  projection_angle   45

void show_screen( );

void Sphere(const int,const int,const int,const int);

void get_projected_point(int&,int&,int&);
void multiply_matrices(const float[4],const float[4][4],float[4]);

int main( )
{
int driver=VGA;
int mode=VGAHI;

int x=0;
int y=0;
int z=0;
int r=0;

do
{
show_screen( );

gotoxy(8,10);
cout<<\"Coordinates of Central Point - (x,y,z) :\";

gotoxy(8,11);
cout<<\"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ\";

gotoxy(12,13);
cout<<\"Enter the value of x = \";
cin>>x;

gotoxy(12,15);
cout<<\"Enter the value of y = \";
cin>>y;

gotoxy(12,17);
cout<<\"Enter the value of z = \";
cin>>z;

gotoxy(8,21);
cout<<\"Radius of the Sphere - r :\";

gotoxy(8,22);
cout<<\"ÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ\";

gotoxy(12,24);
cout<<\"Enter the value of r = \";
cin>>r;

initgraph(&driver,&mode,\"..\\\\Bgi\");

setcolor(15);
Sphere(x,y,z,r);

setcolor(15);
outtextxy(110,460,\"Press <Enter> to continue or any other key to exit.\");

int key=int(getch( ));

if(key!=13)
break;
}
while(1);

return 0;
}

//-----------------------------  Sphere( )  -----------------------------//

void Sphere(const int _x,const int _y,const int _z,const int r)
{
int x=_x;
int y=_y;
int z=_z;

get_projected_point(x,y,z);

for(int angle=2;angle<=r;angle+=5)
{
ellipse(x,y,0,360,r,angle);
ellipse(x,y,0,360,angle,r);
}
}

/************************************************************************/
//---------------------  get_projected_point( )  -----------------------//
/************************************************************************/

void get_projected_point(int& x,int& y,int& z)
{
float fcos0=(f*cos(projection_angle*(M_PI/180)));
float fsin0=(f*sin(projection_angle*(M_PI/180)));

float Par_v[4][4]={
{1,0,0,0},
{0,1,0,0},
{fcos0,fsin0,0,0},
{0,0,0,1}
};

float xy[4]={x,y,z,1};
float new_xy[4]={0};

multiply_matrices(xy,Par_v,new_xy);

x=new_xy[0];
y=new_xy[1];
z=new_xy[2];
}

/************************************************************************/
//----------------------  multiply_matrices( )  ------------------------//
/************************************************************************/

void multiply_matrices(const float matrix_1[4],
const float matrix_2[4][4],float matrix_3[4])
{
for(int count_1=0;count_1<4;count_1++)
{
for(int count_2=0;count_2<4;count_2++)
matrix_3[count_1]+=
(matrix_1[count_2]*matrix_2[count_2][count_1]);
}
}

//--------------------------  show_screen( )  ---------------------------//

void show_screen( )
{
restorecrtmode( );
clrscr( );
textmode(C4350);

cprintf(\"\\n********************************************************************************\");
cprintf(\"*-********************************-          -********************************-*\");
cprintf(\"*---------------------------------- \");

textbackground(1);
cprintf(\" Sphere \");
textbackground(8);

cprintf(\" ----------------------------------*\");
cprintf(\"*-********************************-          -********************************-*\");
cprintf(\"*-****************************************************************************-*\");

for(int count=0;count<42;count++)
cprintf(\"*-*                                                                          *-*\");

gotoxy(1,46);
cprintf(\"*-****************************************************************************-*\");
cprintf(\"*------------------------------------------------------------------------------*\");
cprintf(\"********************************************************************************\");

gotoxy(1,2);
}
```

Didn't find what you were looking for? Find more on Program to draw a Sphere using Ellipses