DDA scan conversion algorithm

Question

Describe in brief regarding the DDA scan conversion algorithm?

Answer 1

Digital differential analyzer (or DDA) is a scan conversion algorithm mainly based on calculation either Δy or Δx by using the given equations:

Δy = m Δx
Δx = Δy/m

Sampling the line at unit intervals in one coordinate and find out corresponding integer values closest to the line path for coordinates.

Sample at X intervals (?x = 1) and calculate each successive Y value as:
Y_k+1 = Y_k + m

For the lines with positive slope more than 1, reverse the roles of X and Y. The sample at unit Y intervals (?y = 1) and compute each successive X value as:

X_k+1 = X_k + 1/m