bluenoise par_bluenoise_set_viewport question

[michalfratczak]

Hi
I'm trying par bluenoise, its very fast ! Thanks for making it public.

While experimenting with it, I noticed par_bluenoise_set_viewport behaviour I didn't expect.
Changing left/right bounds preserves points pattern and returns resonable point counts.
In contrast, changing bottom/top bounds looks totally different and makes point counts less stable.
I recorded a screengrab to illustrate this. Take a look at the end of video, where a slight change in upper bound, causes almost 10x change in generated point count. Is this to be expected ? I'm not really familiar with algorithm's internals.

Thanks for any tips.

https://www.youtube.com/watch?v=-WKOSpt47cg&feature=youtu.be

Here is how I use par blue noise - calling dist_wang_tiles() on each frame.
https://pastebin.com/9dkFm7n8