Reflection in CG

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
void main()
{
 int gd=DETECT,gm,midx,midy;
 initgraph(&gd,&gm,"C:\\TurboC3\\BGI");
 midx=getmaxx()/2;midy=getmaxy()/2;
 line(midx,0,midx,2*midy);
 line(0,midy,2*midx,midy);
 line(midx+150,midy-200,midx+100,midy-100);
 line(midx+100,midy-100,midx+200,midy-100);
 line(midx+200,midy-100,midx+150,midy-200);
 getch();
 setcolor(YELLOW);
 line(midx-150,midy-200,midx-100,midy-100);
 line(midx-100,midy-100,midx-200,midy-100);
 line(midx-200,midy-100,midx-150,midy-200);
 getch();
 setcolor(GREEN);
 line(midx+150,midy+200,midx+100,midy+100);
 line(midx+100,midy+100,midx+200,midy+100);
 line(midx+200,midy+100,midx+150,midy+200);
 getch();
 closegraph();
}