Alpha Shapes algorithm with new cumulative parameter for gradually changes from concave hull to convex hull.

Two implementations are represented. One of them on python 3 and another one on cython.

To execute algorithm run alfa_example.py. You can find example dataset in folder data and some analitics pictures in folder analysis.

The example dataset is part of Petrogradsky district, Saint Petersburg, Russia by Open Street Map. There are 3922 points in the dataset.

Algorithm demonstrates gradually changing from concave hull to convex hull:

Time estimation for datasets with different counts of points shows good performs. For comparison, the implementation of the QGIS for the biggest of these datasets was performed for ~90 minutes.

And additionally hull smoothing was implemented for better demonstration geospatial results: