Can you please explain how this algorithm works?

Question

Python

I needed an algorithm capable of filling with a gradient of any color and any scale.
I found it, but when I try to understand the principle of its operation, I get a mess in my head, even if the algorithm looks very simple.

Here is the code - https://pastebin.com/pdQfV1zZ

Answer 1

I would start by listing the help() documentation for each of the functions used:

Surface((width, height), flags=0, depth=0, masks=None) -> Surface
Surface((width, height), flags=0, Surface) -> Surface
pygame object for representing images

line(surface, color, start_pos, end_pos) -> Rect
line(surface, color, start_pos, end_pos, width=1) -> Rect
draw a straight line

smoothscale(surface, size, dest_surface=None) -> Surface
scale a surface to an arbitrary size smoothly

Without understanding what arguments it takes and what each function returns, it is not possible to understand the algorithm.