Bresenham Line Drawing

Bresenham Line Drawing Algorithm

To draw a line, you need two points between which you can draw a line The Bresenham algorithm is another incremental scan conversion algorithm which is calculate lines coordinates between two points.the points of an n-dimensional raster that should be selected in order to form a close approximation to a straight line between two points.

Code

#include<iostream.h>
#include<conio.h>
#include<math.h>
#include<graphics.h>
void get_driver()
{
clrscr(); //clear screen
int gDriver=DETECT,gMode;
initgraph(&gDriver,&gMode,"C:\\TC\\BGI");
}

void main()
{
get_driver(); //initialize graphics
int dx, dy, p, end;
float x1, x2, y1, y2, x, y;
x1=x2=y1=y2=x=y=p=end=dx=dy=0;
cout<<"Enter the x1 value : ";
cin>>x1;
cout<<"Enter the y1 value : ";
cin>>y1;
cout<<"Enter the x2 value : ";
cin>>x2;
cout<<"Enter the y2 value : ";
cin>>y2;
cleardevice(); //clear Screen for graphics
setbkcolor(15);//set background white
dx = abs(x1 - x2);
dy = abs(y1 - y2);
p = 2 * dy - dx;
if(x1 > x2)
{
x = x2;
y = y2;
end = x1;
}
else
{
x = x1;
y = y1;
end = x2;
}
putpixel(x, y, RED); //put first pixel
while(x < end)
{
x = x + 1;
if(p < 0)
{
p = p + 2 * dy;
}
else
{
y = y + 1;
p = p + 2 * (dy - dx);
}
putpixel(x,y,RED); //put pixel in loop
}
getch();
}

OUTPUT

Bresenham Line Drawing Calculator