rectangle draws a rectangle in the current line style, thickness, and
drawing color.
(left,top) is the upper left corner of the rectangle, and (right,bottom)
is its lower right corner.
/* rectangle example */
#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
int main(void)
{
/* request autodetection */
int gdriver = DETECT, gmode, errorcode;
int left, top, right, bottom;
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, "");
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) { /* an error occurred */
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
}
left = getmaxx() / 2 - 50;
top = getmaxy() / 2 - 50;
right = getmaxx() / 2 + 50;
bottom = getmaxy() / 2 + 50;
/* draw a rectangle */
rectangle(left,top,right,bottom);
/* clean up */
getch();
closegraph();
return 0;
}