**SCAN CONVERTING A STRAIGHT LINE.**

A straight line can be drawn by
plotting discrete point’s b\w the two end points. A device is then directed to
fill in these position b\w the end points. These discrete points along the path
of the line are calculated from equation of the line but the problem with scan
converting straight line is that the pixel positions on the screen are
reference with integer values. This means every point (x, y) along the line
path should have integer value of x and y coordinates so the plotted position
may be approximation of the points on the actual line segment. E.g. actual line
is (15.21, 21.57) then we just do not have a position corresponding to these
values on the raster screen. These points calculated from equation can be
bounded off to (15, 21) which can plot on screen.

**ALGORITHM OF DIRECT METHOD FOR DRAWING A LINE**

1. Input the two-end point of the
line (xi, yi) and (xf, yf)

2. Compute slope of the line, m=
(yf –yi) / (xf- xi)

3. Compute y intercept of the line
b= yi –mx

4. Set initial values of x and y as
x=xi and y=yi

5. Plot the first point, plot pixel
(x, y)

6. if/m/<1 then 7. while (x

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