slides/mongodb/cells.xml
Cells
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GeoJSON: Polygon
Cells for a point
  • • We divide the surface of the earth into cells
  • • A library called S2 from Google does the hard work
  • • Cells have a level which define the size of the cell
  • • S2 provides 31 levels.
  • • Level 0 is a ⅙th of the globe
  • • Each further level devides by 4
  • • The higher the level, the smaller the cell, and therefore the more needed to cover the earth