Comment by Masterjun
2 days ago
I think the original commenter is correct that there is a mistake in the perspective code. It seems the code calculates the linear interpolation for the grid points too late. It should be before projecting, not after.
I opened an issue ticket on the repository with a simple suggested fix and a comparison image.
That admittedly looks a lot more correct! Thanks for digging in, i will absolutely test and submit a correction to the article (i am still concerned the straight edges are misleading here)! And thanks to the original commentor as well! I think I will try to quickly output an animated version of each subdivision level, the animation would make it a lot more clear for me!