4 ms·
Sqaures have overlap if you put them on a sphere, no? There are some nice things with this. It contains cells at different levels (sizes). So you can use very
by Epa095 2y ago
Sqaures have overlap if you put them on a sphere, no?
There are some nice things with this. It contains cells at different levels (sizes). So you can use very small cells if you care about small areas, or large cells if you care more about larger areas. Those are given here https://h3geo.org/docs/core-library/restable/#average-area-in-km2 https://h3geo.org/docs/core-library/restable/#average-area-i...
From a coordinate it is fast to get the cell at any level, so it's fast to group coordinates at whatever level you want.
If is less about comparing two coordinates, it is more about bering able to group large numbers of coordinates such that they go into non-overlapping groups, where everything in the same group is 'close' to each other.
- at0mic22 2y agoI would assume you wouldn't care a lot about overlapping squares as the representation on the screen is mostly square, you don't order uber from the globe. Thus most screen projections are derived from wgs84. The idea behind h3 (as I see it) that when moving the map to lets say top-right, you'd need to fetch 1 leaf comparing to 3 leafs with rtree
- jillesvangurp 2y agoMost grid systems don't have overlapping squares because they are quad trees. Each point identifies a single rectangle they are in, and all the parent rectangles that fully contain that rectangle. H3 doesn't have that property between levels. Cells at a level don't overlap. But the the seven children of a cell might overlap with neighboring parent cells. Of course rectangles aren't rectangular when projected on a sphere. Because there are no straight lines. Rectangles and hexagons are 2d shapes that are applied to the 2d projections of spheres. They only look like rectangles or hexagons in 2D.