ADJUSTING SPATIAL OPERATIONS BASED ON MAP DENSITY

• US 20080270468A1
• Filed: 04/25/2007
• Published: 10/30/2008
• Est. Priority Date: 04/25/2007
• Status: Active Grant

• Current Assignee: MiTAC International Corporation (MiTAC Holdings Corp.)
• Original Assignee: Magellan Navigation Incorporated (MiTAC Holdings Corp.)
• Inventors: Lokshin, Anatole, Upparapalli, Nidhi, Mao, Ailin
• Granted Patent: US 8,078,641 B2
• Time in Patent Office: Days
• US Class Current: 707/104.1
• CPC Class Codes: G06F 16/29 Geographical information databases

Abstract

A method of determining density of a map is described along with an apparatus and computer-readable medium comprising instructions therefore. The method comprises determining one or more nodes of a quad tree applied to a map with which a predetermined query region intersects, calculating a cumulative data size of the query region based on a data size of the one or more intersecting nodes, and determining an average density of the query region based on the query region area and the cumulative data size.

Claims

1. A method of determining density of a region of a map, comprising:

determining one or more nodes of a quad tree applied to a map with which a predetermined query region intersects;

calculating a cumulative data size of the query region based on a data size of the one or more intersecting nodes; and

determining an average density of the query region based on the query region area and the cumulative data size.

2. The method as claimed in claim 1, further comprising storing the determined query region density to a memory.

3. The method as claimed in claim 1, further comprising outputting the determined query region density to an output device.

4. The method as claimed in claim 1, wherein calculating comprises:

adjusting the query region data size by an amount corresponding to the data size of a node enclosed by the query region; and

adjusting the query region data size by an amount corresponding to the data size of a node proportional to the intersection area of the query region and the node.

5. The method as claimed in claim 1, further comprising:

specifying the predetermined query region based on at least one of user input, and a predetermined map display.

6. The method as claimed in claim 1, wherein the determining comprises a query region in rectangular form.

7. The method as claimed in claim 1, wherein the adjusting is performed for each of the one or more intersecting nodes.

8. The method as claimed in claim 1, further comprising:

automatically adjusting at least one of a detail level and a layer visibility of the map used to generate a map display having a feature density corresponding to a predetermined map feature density.

9. The method as claimed in claim 8, wherein determining a density comprises determining a map density for at least one of one or more detail levels of the map and enabling visibility of one or more map layers.

10. The method as claimed in claim 9, wherein automatically adjusting comprises at least selecting one predefined detail level of the map.

11. The method as claimed in claim 9, wherein automatically adjusting comprises at least one of enabling visibility of one or more map layers and disabling visibility of one or more map layers.

12. The method as claimed in claim 9, wherein automatically adjusting is performed for a determined map density greater than a predetermined maximum density threshold.

13. The method as claimed in claim 9, wherein automatically adjusting is performed for a determined map density less than a predetermined minimum density threshold.

14. The method as claimed in claim 9, further comprising:

generating the map display based on the adjusted parameter.

15. The method as claimed in claim 1, wherein determining density of selected map layers comprises determining street routing quality criteria.

16. The method as claimed in claim 15, wherein the route quality criteria comprise at least one of urban route criteria and rural route criteria.

17. The method as claimed in claim 15, wherein determining street routing quality criteria comprising urban route criteria is selected for a determined map density greater than a predetermined minimum urban density.

18. The method as claimed in claim 15, wherein determining street routing quality criteria comprising rural route criteria is selected for a determined map density less than a predetermined minimum urban density.

19. The method as claimed in claim 1, wherein determining map data size inside a query rectangle comprises enlarging a search radius by a predetermined amount for a determined map data size greater than a predetermined minimum data size.

20. The method as claimed in claim 19, further comprises searching for objects to be displayed within the enlarged map radius.

21. A mobile computer device for determining density of a map, the device comprising:

a processor;

a memory communicatively coupled with the processor and comprising a set of instructions which, when executed by the processor, cause the processor to;

determine one or more nodes of a quad tree applied to a map with which a predetermined query region intersects;

calculate a cumulative data size of the query region based on a data size of the one or more intersecting nodes; and

determine a density of the query region based on the query region area and the cumulative data size.

22. The mobile computer device as claimed in claim 21, further comprising instructions which, when executed by the processor, cause the processor to store the determined query region density to the memory.

23. The mobile computer device as claimed in claim 21, wherein the instructions which cause the processor to calculate a cumulative data size further comprise instructions which, when executed by the processor, cause the processor to adjust the data size in the query region by an amount corresponding to the data size of a node enclosed by the query region and adjust the query region data size by an amount corresponding to the data size of a node proportional to the intersection area of the query region and the node.

24-27. -27. (canceled)

28. A computer-readable medium storing instructions which, when executed by a processor, cause the processor to determine one or more nodes of a quad tree applied to a map with which a predetermined query region intersects;

calculate a cumulative data size of the query region based on a data size of the one or more intersecting nodes; and

determine an average density in the query region based on the query region area and the cumulative data size.

29. The computer-readable medium as claimed in claim 28, wherein the instructions which cause the processor to calculate a cumulative data size further comprise instructions which, when executed by the processor, cause the processor to adjust the query region data size by an amount corresponding to the data size of a node enclosed by the query region and adjust the query region data size by an amount corresponding to the data size of a node proportional to the intersection area of the query region and the node.

30-33. -33. (canceled)