Complete C program to demonstrate rectangles using putpixel and lines
#include<graphics.h>
#include<conio.h>
#include<stdlib.h>
#include<dos.h>
void main()
{
int gm,gd=DETECT;
int x1,x2,y1,y2,c,I;
initgraph(&gd,&gm,’’’’);
while(!kbhit())/*until pressing any key this loop continues*/
{
/*for rectangle co-ordinates are taken randomly*/
x1=rand()%getmaxx();
x2=rand()%getmaxx();
y1=rand()%getmaxy();
y2=rand()%getmaxy();
if(x1>x2)
{
c=x1; /* exchange of x1 and x2 when x1 >x2 */
x1=x2;
x2=c;
}
if(y1>y2)
{
c=y1; /* exchange of y1 and y2 when y1>y2 */
y1=y2;
y2=c;
}
c=rand()%16;
/*to draw rectangle using putpixel*/
for(I=x1;I<=x2;++i)
{
putpixel(I,y1,c);
delay(1);
}
for(I=y1;I<=y2;++i)
{
putpixel(x2,I,c);
delay(1);
}
for(I=x2;I>=x1;_- i)
{
putpixel(I,y2,c);
delay(1);
}
for(I=y2;I>y1;-I)
{
putpixel(x1,I,c);
delay(1);
}
delay(200); /* to draw the pixels slowly */
}
getch();
closegraph(); /* closes the graph mode */
}