REDUCING OCCLUSIONS IN OBLIQUE VIEWS

• US 20080180439A1
• Filed: 01/29/2007
• Published: 07/31/2008
• Est. Priority Date: 01/29/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Toyama, Kentaro, Adabala, Neeharika
• Granted Patent: US 8,253,736 B2
• Time in Patent Office: Days
• US Class Current: 345/421
• CPC Class Codes: G06T 11/206 Drawing of charts or graphs
• CPC Class Codes: G06T 15/20 Perspective computation
• CPC Class Codes: G06T 17/05 Geographic models

Abstract

An occlusion reduction system is described. The occlusion reduction system can reduce occlusions when displaying multiple objects by computing an occlusion measure and applying one or more functional dynamics techniques to minimize the occlusion measure, such as by moving objects, making objects at least partially transparent, and altering the scale of objects. The occlusion reduction system can create a geometric model based on modeling information it receives, establish a viewpoint, identify a set of objects for analysis, and compute an occlusion measure for the identified set of objects.

Claims

1. A method performed by a computing system for reducing occlusions when displaying multiple objects, comprising:

creating a geometric model based on modeling information, the created geometric model identifying at least two objects;

receiving a selection of a viewpoint, the viewpoint establishing a perspective from which the geometric model is to be displayed;

identifying from the created geometric model a set of objects for analysis;

analyzing the identified set of objects to compute an occlusion measure, the occlusion measure measuring an extent to which objects are occluded; and

when the occlusion measure exceeds the threshold occlusion value, improving visibility of the occluded objects by applying a functional dynamics technique.

2. The method of claim 1 wherein the functional dynamics technique comprises moving an occluding object to improve the visibility of the occluded objects.

3. The method of claim 2 wherein the moving includes determining an extent to which the occluding object can be moved.

4. The method of claim 3 wherein when the occluding object is a building, the extent is a road.

5. The method of claim 1 wherein the functional dynamics technique comprises making an occluding object at least partially transparent to improve the visibility of the occluded objects.

6. The method of claim 5 wherein when a first occluding object at least partially occludes a second occluding object and the first and second occluding objects at least partially occlude an occluded object, the occluded object is displayed as opaque and the first occluding object is displayed with greater transparency than the second occluding object.

7. The method of claim 1 wherein the functional dynamics technique comprises modifying a height of an occluding object to improve the visibility of the occluded objects.

8. The method of claim 1 wherein the functional dynamics technique comprises moving a first occluding object, making a second occluding object at least partially transparent, and modifying a height of a third occluding object.

9. The method of claim 8 wherein at least two of the first, second, or third occluding objects are the same occluding object.

10. The method of claim 1 wherein the occlusion measure is computed by computing an occlusion value for each object in the identified subset of the group of objects and summing the computed occlusion values.

11. The method of claim 10 wherein the occlusion value for each object represents a fraction of a portion of the object that would be visible from the viewpoint but is occluded by other objects and the occlusion value is an occlusion index.

12. A system for reducing occlusions when displaying multiple objects, comprising:

a set of modeling information that describes a geometric model of a group of objects that can be displayed;

a transformation component that receives the set of modeling information and a selection of a viewpoint, the viewpoint establishing a perspective from which the geometric model is to be displayed, and transforms the modeling information into viewing information that identifies a subset of the group of objects that are to be displayed; and

a functional dynamics component that computes an occlusion index that measures an extent to which objects are occluded by occluding objects, determines whether the occlusion index exceeds a threshold occlusion value, and when the occlusion index exceeds the threshold occlusion value, improves visibility of the occluded objects by applying a functional dynamics technique.

13. The system of claim 12 wherein the functional dynamics component can move an occluding object to improve visibility of an occluded object.

14. The system of claim 12 wherein the functional dynamics component can make an occluding object at least partially transparent to improve visibility of an occluded object wherein a level of transparency is based on a distance from the viewpoint to the occluding object.

15. The system of claim 12 wherein the functional dynamics component can scale an occluding object to improve visibility of an occluded object by performing a non-uniform scaling operation.

16. The system of claim 12 wherein the functional dynamics component computes the occlusion index by analyzing an extent to which each object that is to be displayed is occluded by other objects that are also to be displayed and applies the functional dynamics technique to minimize the computed occlusion index.

17. A computer-readable medium storing computer-executable instructions that, when executed, cause a computing system to perform a method for reducing occlusions when displaying multiple objects, the method comprising:

computing an occlusion measure for a set of objects, the occlusion measure measuring an extent to which objects are occluded; and

when the occlusion measure exceeds the threshold occlusion value, improving visibility of the occluded objects by applying a functional dynamics technique.

18. The computer-readable medium of claim 17 wherein the functional dynamics technique comprises moving an object.

19. The computer-readable medium of claim 17 wherein the functional dynamics technique comprises making an object at least partially transparent.

20. The computer-readable medium of claim 17 wherein the functional dynamics technique comprises altering a size of an object.