Gustry/GeoHealth

Blur does not seem to work

belg4mit opened this issue · 3 comments

The help suggests that the plugin will do:

1 : Creating a buffer (radius r)
2 : Random selection of a point in each buffer
3 : Creating a buffer around the new point with the same radius. The initial point is at a maximal distance 2r of the centroid of the buffer.
4 : Deleting the random point and the first buffer

However, it seems to stop after step 1 for me.

Also, I recommend adding the keyword jitter to the plugin description, since this is a (more?) common name for this type of obfuscation; more typically done by simply adding two random value in the range of -r to +r to the coordinates of the point, no buffers required.

The help suggests that the plugin will do:

Thanks, this is the theory. In practical, the plugin has a random angle between 0 and 2∏ and a random distance between 0 and r (if I remember correctly).

Checking quickly: https://github.com/Gustry/GeoHealth/blob/master/src/core/blurring/blur.py#L39
And this is only doing a new point with polar coordinates. So I don't know what is happening in your case. Do you have any screenshot?

Thanks for jitter! I will add it.

I'd like to, but I just updated 2.18 to verify something else was broken, and the plugin does not load in 2.18.6... I had been using 2.18.0-1

I opened my backup 2.12 and I guess I was using an older version of the plugin? It did not have the right panel help, but instead a separate tab. However the right panel help in this version makes it clear that the it is behaving as intended? It says the output is a polygon, which is what I'm getting. However, I was actually hoping for jittered points, something similar to what I described or even what you described... a new point layer with points that are offset at a random angle and random distance (within a threshold) from the original points.

However, I was actually hoping for jittered points, something similar to what I described or even what you described... a new point layer with points that are offset at a random angle and random distance (within a threshold) from the original points.

For now, we only output the polygon layer. We can add the point layer too if you want.