Computer GraphicsDDA LINE

#include"stdio.h"
#include"graphics.h"

#include"math.h"

main()

{

float x,y,x1,y1,x2,y2,dx,dy,length;

int i,gd,gm;

clrscr();
/* Read two end points of line---------------------------------- */
printf("Enter the value of x1 :\t");

scanf("%f",&x1);

printf("Enter the value of y1 :\t");

scanf("%f",&y1);

printf("Enter the value of x2 :\t");

scanf("%f",&x2);

printf("Enter the value of y2 :\t");

scanf("%f",&y2);
/* Initialise graphics mode---------------------------------- */
detectgraph(&gd,&gm);

initgraph(&gd,&gm,"");
dx=abs(x2-x1);

dy=abs(y2-y1);
if (dx >= dy)

{

length = dx;

}

else

{

length = dy;

}

dx = (x2-x1)/length;

dy = (y2-y1)/length;
x = x1 + 0.5;

/* Factor 0.5 is added to round the values */

y = y1 + 0.5;

/* Factor 0.5 is added to round the values */
i = 1;

/* Initialise loop counter */

while(i <= length)

{

putpixel(x,y,15);

x = x + dx;

y = y + dy;

i = i + 1;

delay(100);

/* Delay is purposely inserted to see observe the line drawing process */

}

getch();

closegraph();
}