s2 python

s2 python.ipynb

s2 python.py

# coding: utf-8

# In[1]:


import folium
import pywraps2 as s2


# In[2]:


# create a rect in s2
region_rect = s2.S2LatLngRect(
        s2.S2LatLng.FromDegrees(48.831776, 2.222639),
        s2.S2LatLng.FromDegrees(48.902839, 2.406))


# In[3]:


# ask s2 to create a cover of this rect
coverer = s2.S2RegionCoverer()
coverer.set_min_level(10)
coverer.set_max_level(30)
coverer.set_max_cells(60)
covering = coverer.GetCovering(region_rect)
print([c.ToToken() for c in covering])


# In[4]:


# create a map
map_osm = folium.Map(location=[48.86, 2.3],zoom_start=12, tiles='Stamen Toner')

# get vertices from rect to draw them on map
rect_vertices = []
for i in [0, 1, 2, 3, 0]:
    vertex = region_rect.GetVertex(i)
    rect_vertices.append([vertex.lat().degrees(), vertex.lng().degrees()])
    
# draw the cells
style_function = lambda x: {'weight': 1, 'fillColor':'#eea500'}
for cellid in covering:
    cell = s2.S2Cell(cellid)
    vertices = []
    for i in range(0, 4):
        vertex = cell.GetVertex(i)
        latlng = s2.S2LatLng(vertex)
        vertices.append([latlng.lng().degrees(),
                         latlng.lat().degrees()])
        
    gj = folium.GeoJson({ "type": "Polygon", "coordinates": [vertices]}, style_function=style_function)
    gj.add_children(folium.Popup(cellid.ToToken()))
    gj.add_to(map_osm)
    
# warning PolyLine is lat,lng based while GeoJSON is not
ls = folium.PolyLine(rect_vertices, color='red', weight=2)
ls.add_children(folium.Popup("shape"))
ls.add_to(map_osm)
    
map_osm