I am creating a drawing based on an algorithm in which many cursors will move according to a pseudo-random path and paint the pixels in their paths with a somewhat transparent color. Multiple passes on the same pixel will render it slightly darker.
Unfortunately, for some reason I still fail to understand, as the drawing evolves, a black orthogonal cross starts to appear at the (0,0) axis.
This suggests that the cursors tend to walk on average more on that cross than everywhere else. But this doesn’t seem to make sense because my cursors move in all directions and they don’t even start at the (0,0) position.
Here it an example of the problem:
And here’s a version of the code which has this problem:
The two classes responsible for this drawing are Hypha and Hyphae.