Thank you, Martin. This is exactly what I was searching for. In the meanwhile, I put all the table in the wiki table if someone is interested in complete the description of the full schema.
Best, Lorenzo > Il giorno 14 gen 2020, alle ore 11:25, Martin Raifer <[email protected]> ha > scritto: > > I believe the formula just implements the interleaving of the X and Y > coordinates used in the QuadTiles[1] indexing schema in an efficient > way by using some clever bit operations. > > [1] https://wiki.openstreetmap.org/wiki/QuadTiles#Quadtile_implementation > > On Tue, Jan 14, 2020 at 11:11 AM Lorenzo Stucchi > <[email protected]> wrote: >> >> Hi all, >> >> I have almost complete the explanation of the schema regarding the element >> (node, way and relation) I have just one last element to be understood. >> >> The “tile” in the node table. I found in the code a function called >> “public.tile_for_point” [1] and seems that should be the one that do this >> process. But I’m not able to understood which is the output of the function, >> in particular what this part of code does: >> >> x := (x | (x << 8)) & 16711935; — 0x00FF00FF >> >> Thanks for all the reply. >> >> Best, >> Lorenzo >> >> [1] >> https://github.com/openstreetmap/openstreetmap-website/blob/751e8ad32c864f50eae9e9359d74a11dc44de007/db/structure.sql#L160 >> >> Il giorno 10 gen 2020, alle ore 15:51, Lorenzo Stucchi >> <[email protected]> ha scritto: >> >> Thanks for the reply. >> >> Is this the formula [1] ? >> >> Best, >> Lorenzo >> >> [1] >> https://github.com/openstreetmap/openstreetmap-website/blob/751e8ad32c864f50eae9e9359d74a11dc44de007/db/structure.sql#L160 >> >> Il giorno 10 gen 2020, alle ore 15:22, Frederik Ramm <[email protected]> >> ha scritto: >> >> Hi, >> >> On 10.01.20 15:08, Lorenzo Stucchi wrote: >> >> What does it mean the “timestamp” present in the table (“node", “way" and >> “relation")? >> >> >> When the object was last changed. >> >> What does it mean the “tile” element present in the “node" table? >> >> >> An integer derived from the lat/lon of the node using a mathematical >> formula. >> >> What does it mean the “sequence_id” in the “way_nodes” table and >> “relation_member” table? >> >> >> An integer used to store the ordering of the nodes/members (which node >> is the first, the second, ... in the way). >> >> Bye >> Frederik >> >> -- >> Frederik Ramm ## eMail [email protected] ## N49°00'09" E008°23'33" >> >> _______________________________________________ >> dev mailing list >> [email protected] >> https://lists.openstreetmap.org/listinfo/dev >> >> >> _______________________________________________ >> dev mailing list >> [email protected] >> https://lists.openstreetmap.org/listinfo/dev >> >> >> _______________________________________________ >> dev mailing list >> [email protected] >> https://lists.openstreetmap.org/listinfo/dev _______________________________________________ dev mailing list [email protected] https://lists.openstreetmap.org/listinfo/dev
