Dynamic vector map tiles

1. A computer-implemented method comprising:

at one or more servers:

receiving, from an electronic device, a request for a vector map sub-tile; identifying a vector map tile corresponding to the requested vector map sub-tile; accessing the vector map tile;

generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles, the plurality of vector map sub-tiles comprising the requested vector map sub-tile, wherein the vector map tile comprises one or more of a point map feature, line map feature, polygon map feature, or a three-dimensional (3D) polygon map feature, and dividing the vector map tile into the plurality of vector map sub-tiles comprises selecting one of a plurality of processes for dividing the vector map tile depending upon the map feature within the vector map tile; and

transmitting the requested vector map sub-tile to the electronic device.

2. The computer-implemented method of claim 1 , wherein the vector map tile comprises vector data representing a portion of a map.

3. The computer-implemented method of claim 1 , wherein accessing the vector map tile comprises:

retrieving the vector map tile from a storage of the one or more servers; and

decoding the vector map tile from an encoding format.

4. The computer-implemented method of claim 3 , wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises dividing the decoded vector map tile.

5. The computer-implemented method of claim 3 further comprising:

at the one or more servers, encoding the requested vector map sub-tile into the encoding format prior to transmitting the requested vector map sub-tile to the electronic device.

6. The computer-implemented method of claim 1 , wherein the vector map tile comprises a point map feature, and wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises:

at the one or more servers:

determining whether the point map feature is located within the requested vector map sub-tile;

in accordance with a determination that the point map feature is located within the requested vector map sub-tile, generating the requested vector map sub-tile to include the point map feature; and

in accordance with a determination that the point map feature is not located within the requested vector map sub-tile, generating the requested vector map sub-tile to exclude the point map feature.

7. The computer-implemented method of claim 6 , wherein the point map feature represents a point of interest.

8. The computer-implemented method of claim 1 , wherein the vector map tile comprises a line map feature, and wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises:

at the one or more servers:

determining whether the line map feature is located within the requested vector map sub-tile;

in accordance with a determination that the line map feature is not at least partially located within the requested vector map sub-tile, generating the requested vector map sub-tile to exclude the line map feature;

in accordance with a determination that the line map feature is located entirely within the requested vector map sub-tile, generating the requested vector map sub-tile to include the line map feature; and

in accordance with a determination that the line map feature is located partially within the requested vector map sub-tile:

applying a flattening algorithm to the line map feature;

generating a plurality of line segments by dividing the flattened line map feature at intersections between vector map sub-tiles of the plurality of vector map sub-tiles;

applying a curve fitting algorithm to one or more line segments of the plurality of line segments located within the requested vector map sub-tile; and

generating the requested vector map sub-tile to include the one or more line segments.

9. The computer-implemented method of claim 8 further comprising:

at the one or more servers:

in accordance with a determination that the line map feature is located partially within the requested vector map sub-tile, tagging ends of the one or more line segments located at an edge of the requested vector map sub-tile to indicate that the one or more line segments connect to other line segments of other vector map sub-tiles.

10. The computer-implemented method of claim 8 , wherein the line map feature represents a road, a path, a highway, or a river.

11. The computer-implemented method of claim 1 , wherein the vector map tile comprises a polygon map feature, and wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises:

at the one or more servers:

determining whether the polygon map feature is located within the requested vector map sub-tile;

in accordance with a determination that the polygon map feature is not at least partially located within the requested vector map sub-tile, generating the requested vector map sub-tile to exclude the polygon map feature;

in accordance with a determination that the polygon map feature is located entirely within the requested vector map sub-tile, generating the requested vector map sub-tile to include the line polygon feature; and

in accordance with a determination that the polygon map feature is located partially within the requested vector map sub-tile:

generating a plurality of polygon segments by dividing the polygon map feature at intersections between vector map sub-tiles of the plurality of vector map sub-tiles; and

generating the requested vector map sub-tile to include one or more polygon segments of the plurality of polygon segments located within the requested vector map sub-tile.

12. The computer-implemented method of claim 11 further comprising:

at the one or more servers:

in accordance with a determination that the polygon map feature is located partially within the requested vector map sub-tile, tagging edges of the one or more polygon segments located at an edge of the requested vector map sub-tile to indicate that the tagged edges represent interior edges.

13. The computer-implemented method of claim 11 , wherein the line polygon map feature represents a body of water or an area of land.

14. The computer-implemented method of claim 1 , wherein the vector map tile comprises a three-dimensional (3D) polygon map feature, the 3D polygon map feature having a two-dimensional (2D) base, and wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises:

at the one or more servers:

determining whether the requested vector map sub-tile is a vector map sub-tile of the plurality of vector map sub-tiles having a largest portion of the 2D base located therein;

in accordance with a determination that the requested vector map sub-tile is the vector map sub-tile of the plurality of vector map sub-tiles having the largest portion of the 2D base located therein, generating the requested vector map sub-tile to include the 3D polygon map feature; and

in accordance with a determination that the requested vector map sub-tile is not the vector map sub-tile of the plurality of vector map sub-tiles having the largest portion of the 2D base located therein, generating the requested vector map sub-tile to exclude the 3D polygon map feature.

15. The computer-implemented method of claim 14 , wherein the line 3D polygon map feature represents a building.

16. The computer-implemented method of claim 1 , wherein generating the requested vector map sub-tile by dividing the vector map tile into a plurality of vector map sub-tiles comprises:

at the one or more servers:

generating the requested vector map sub-tile to include one or more attributes of the vector map tile.

17. The computer-implemented method of claim 16 , wherein the one or more attributes comprises a local North direction.

18. The computer-implemented method of claim 1 , wherein the electronic device is a watch.

19. The computer-implemented method of claim 1 , wherein the electronic device is a mobile phone.