As with the "Computer Graphics" programming holds, the Bresenham's Line Drawing Algorithm is one cool algo to play with. There's no pixel overlapping and it's kinda easy too. Here's the C codes for the program, just copy it out and see for yourself.
#include
#include
#include
#include
void main()
{
clrscr();
/* (x0,y0) and (x1,y1) the end points of the line,
dx = difference of the x co-ordinates,
dy = differenc of the y co-ordinates
p = descision parameter */
int x0,y0,x1,y1,dx,dy,x,y,xend,p,gd=DETECT,gm;
initgraph(&gd,&gm,"C:\\TC\\BGI");
printf("Enter x0,y0,x1,y1 :");
scanf("%d%d%d%d",&x0,&y0,&x1,&y1);
dx=abs(x0-x1); //Calculating the difference of the x co-ordinates
dy=abs(y0-y1); //Calculating the difference of the y co-ordinates
p=2*dy-dx; //descision parameter
/* The if-else statement puts the left coordinate out of the two ends in x0,y0 */
if(x0>x1)
{
x = x1;
y = y1;
xend=x0;
}
else
{
x=x0;
y=y0;
xend=x1;
}
putpixel(x,y,1); // puts the pixels on the screen
while(x< xend)
{
x++;
if(p<0) // for p<0
{
p=p+2*dy;
}
else // for p>0
{
y++;
p=p+2*(dy-dx);
}
putpixel(x,y,1);
}
getch();
}
