Algorithm and Function of Mid Point Circle Algorithm.

Mid Point Circle Algorithm :

Begin:

   Read (Xc,Yc) and r

   P = 1 – r, x  = 0, y = r

   while(X<=Y)

      plot(X,Y)

      X = X+1

          If (p<=0)

         {

          P=P+2X-1

         }

          else

          {

                Y=Y-1

                P=P+2(X-Y)+1

          }

         end if

     end of while

  

End 

  

Function of Mid Point Circle :

 

void circlemidpoint(int xc,int yc,int r)

 {

      int x=0;

      int y=r;

      int p =1-r;

      point( xc, yc,x,y);

      while(x<y)

      {

            x++;

            if(p<0)

            p+=2*x+1;

           else

           {

                y--;

                p+=2*(x-y)+1;

           }

          point(xc,yc,x,y);

       }

}

void point(int xc,int yc,int x,int y)

 {

     putpixel(xc+x,yc+y,58);

     putpixel(xc+y,yc+x,58);

     putpixel(xc-y,yc+x,58);

     putpixel(xc-x,yc+y,58);

     putpixel(xc+x,yc-y,58);

     putpixel(xc-y,yc-x,58);

     putpixel(xc+y,yc-x,58);

     putpixel(xc-x,yc-y,58);

}