Assumption regarding to the Digital Differential Analyzer Algorithm
The line generation by DDA is discussed merely for the first Quadrant, whether the line lies in the other quadrant then apply respective transformation usually reflection transformation, thus it lies in first Quadrant and then proceed along with the algorithm, as well make intercept Zero through translational transformation so (xi, yi) solves to (xi, mxi + c) or (xi, mxi) and related simplification arises for the other cases of line generation. The idea and application of transformations is discussed in further course.