Docs: Improve docstring for DDA algorithm (#13906)

* Docs: Improve docstring for DDA algorithm

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* Fix typo in DDA algorithm description

Corrected a typo in the comment regarding the DDA algorithm.

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Christian Clauss <cclauss@me.com>

graphics/digital_differential_analyzer_line.py

@@ -21,6 +21,15 @@ def digital_differential_analyzer_line(
     Despite this, DDA is useful for educational purposes as it is simple
     to understand and demonstrates the basic idea of incremental line generation.
 
+    This algorithm works by calculating the dx (change in x) and dy (change in y) and
+    then iteratively steps along the dominant axis, incrementing the other axis by a
+    fractional amount (the slope).
+    It is notable for its simplicity but also for its main disadvantage:
+    * it relies on floating-point arithmetic at every step, which is computationally
+      slow.
+    * it is generally outperformed by Bresenham's algorithm, which achieves the same
+      result using only integer-based math.
+
     Args:
       - p1: Coordinates of the starting point.
       - p2: Coordinates of the ending point.