Generating a display image

• US 9,019,302 B2
• Filed: 05/29/2008
• Issued: 04/28/2015
• Est. Priority Date: 05/29/2008
• Status: Active Grant

• Current Assignee: TomTom Navigation B.V (TomTom NV)
• Original Assignee: TomTom International BV (TomTom NV)
• Inventors: Geelen, Pieter, Martens, David
• Primary Examiner(s): Johnson, M Good
• Application Number:
  US12/736,674
• Publication Number:
  US 20110141138A1
• Time in Patent Office: 2,525 Days
• Field of Search: 345/619, 701/455
• US Class Current: 345/619
• CPC Class Codes: G01C 21/36 Input/output arrangements for on-board computers

Abstract

A method, computer program and apparatus are disclosed for generating a display image for a navigation device, wherein the display image includes a map view for display on the navigation device and the map view includes a two dimensional plan view. At least one embodiment of the method includes identifying a plurality of map objects from a digital map for display in a display image on a navigation device; determining whether any of the identified map objects include one or more non-visible features that would not be visible to a user of the navigation device at ground level; generating an adapted set of map objects that does not include any of the non-visible features; and generating, from the adapted set of map objects, a simplified display image for display on the navigation device, wherein the simplified display image does not include any of the non-visible features.

Claims

1. A method for generating a display image for a navigation device, wherein the display image includes a map view for display on the navigation device and the map view comprises a two dimensional plan view, the method comprising:

identifying, using a processor, a plurality of map objects from a digital map for display in a display image on a navigation device, each of the map objects comprising a set of coordinate data points that together define a polygon;

identifying, using the processor, an outermost boundary defined by at least part of the set of coordinate data points;

determining, using the processor, that said map object includes one or more non-visible features if said set is determined to include any further coordinate data points within said boundary, non-visible features being features that are not visible to a user at ground level outside of the boundary;

generating, using the processor, an adapted set of map objects that does not include any of said non-visible features; and

generating, from said adapted set of map objects, a simplified display image for display on the navigation device, wherein said simplified display image does not include any of said non-visible features, using the processor.

2. A method according to claim 1, wherein each said map object defines a feature of said digital map for display in said display image, said display map includes a plurality of different types of features, and each said map object includes an indication of the type of feature that that map object relates to.

3. A method according to claim 2, wherein at least one of said features is a non-visible feature, and said step of generating an adapted set of map objects comprises the steps of identifying which of said map objects relate to a non-visible feature and selecting map objects other than said identified map objects for inclusion in said adapted set of map objects.

4. A method according to claim 3, wherein said non-visible feature comprises a courtyard.

5. A method according to claim 1, wherein said step of generating an adapted set of map objects comprises, for each said map object that is determined to include one or more non-visible features, the step of discarding all coordinate data points within said boundary to thereby provide an adapted map object for inclusion in said adapted set of map objects.

6. A method according to claim 5, wherein said adapted set of map objects comprises said adapted map objects and any map objects that are determined, in said determining step, not to include any non-visible features.

7. A method according to claim 1, wherein each said map object comprises at least one constituent part that includes a plurality of data points defining a polygon.

8. A method according to claim 7, wherein said determining step comprises determining whether said map object includes a plurality of parts that each includes a plurality of coordinate data points, and identifying any map objects that are determined to have a plurality of constituent parts to be a map object that includes at least one non-visible feature.

9. A method according to claim 8, wherein said step of generating an adapted set of map objects comprises, for each said map object that is determined to include one or more non-visible features, the step of discarding any constituent parts other than a first part that defines an outermost boundary of said map object to thereby provide an adapted map object for inclusion in said adapted set of map objects.

10. A method according to claim 1, wherein each said map object relates to a building in said digital map and defines one or more features of said building.

11. A computer program product, comprising executable software present on a non-transitory computer readable medium which, when executed by a computer processor, implements the method as defined by claim 1.

12. A navigation apparatus comprising a processor configured to generate a display image comprising a two-dimensional plan map view and a display screen configured to display said display image, wherein the processor is further configured to

identify a plurality of map objects from a digital map for display in the display image, each of the map objects comprising a set of coordinate data points that together define a polygon;

identify an outermost boundary defined by at least part of the set of coordinate data points;

determine that said map object includes one or more non-visible features if said set is determined to include any further coordinate data points within said boundary, non-visible features being features that are not visible to a user at ground level outside of the boundary;

generate an adapted set of map objects that does not include any of said non-visible features; and

generate, from said adapted set of map objects, a simplified display image to be displayed on the display screen, wherein said simplified display image does not include any of said non-visible features.

13. The navigation apparatus of claim 12, wherein the processor is further configured to infill the determined non-visible features with a graphic associated with said map object.

14. The navigation apparatus of claim 12, wherein the determination of whether said map object includes one or more non-visible features further comprises:

acquiring coordinate data points that define said map object when said map object is included within a map view;

analysing the acquired coordinate data points for said map object to determine whether said map objects includes one or more non-visible features; and

flagging said map objects for further processing when said map object includes one or more non-visible features.

15. The navigation apparatus of claim 12, wherein the processor is further configured to:

calculate a route; and

superpose said route onto said simplified display image.