Derivative-based selection of zones for banded map display
AssigneeGoogle Inc.
InventorBrian Cornell
Life of this patent
Estimating the term…
Abstract
A graphics or image rendering system, such as a map image rendering system, determines a viewing window of a map surface to be displayed, wherein the viewing plane is at an angle of incidence with respect to the map surface. The method generally determines a depth boundary along the map surface where a height projection of a depth increment of a first unit of area is lower than a threshold height increment at a non-zero angle of incidence and at a single zoom level magnification. The method renders the first unit of area within the depth boundary and a second unit of area outside the depth boundary. The first unit of area is rendered at a first density of map data and the second unit of area is rendered at a second density of map data that is lower than the first density of map data.
Claims20
A computer-implemented method for rendering a three-dimensional map on a display device comprising:
- determining, using a computer device, a map surface plane and a viewing plane, wherein the viewing plane is at a non-zero angle of incidence with respect to the map surface plane;
- determining, using the computer device, a first unit of area on the map surface plane, the first unit of area representing a map area viewed at a first zoom level through the viewing plane when the viewing plane is at a zero angle of incidence with respect to the map surface plane, wherein the first unit of area has two dimensions along the map surface plane;
- calculating, using the computer device, a projection of a first dimension along the map surface plane of the first unit of area onto a first dimension along the viewing plane at the non-zero angle of incidence with respect to the map surface plane;
- determining, using the computer device, if the projection is at a threshold of the viewing plane, wherein the threshold relates to a length on the viewing plane;
- determining, using the computer device, a boundary on the viewing plane when the projection is determined to be at the threshold such that the location of the boundary changes as a function of a change in the non-zero angle of incidence;
- and
- rendering on the viewing plane a projection of a first area of the map surface plane on one side of the boundary using a first density of map data and rendering a projection of a second area of the map surface plane on a second side of the boundary using a second density of map data lower than the first density of map data.
A computer device comprising:
- a communications network interface;
- one or more processors;
- one or more memories coupled to the one or more processors;
- a display device coupled to the one or more processors;
- wherein the one or more memories include computer executable instructions stored therein that, when executed by the one or more processors, cause the one or more processors to:
- determine a map surface plane and a viewing plane, wherein the viewing plane is at a non-zero angle of incidence with respect to the map surface plane;
- determine a first unit of area on the map surface plane, the first unit of area representing a map area viewed at a first zoom level through the viewing plane when the viewing plane is at a zero angle of incidence with respect to the map surface plane, wherein the first unit of area has two dimensions along the map surface plane;
- calculate a projection of a first dimension along the map surface plane of the first unit of area onto a first dimension along the viewing plane at the non-zero angle of incidence with respect to the map surface plane;
- determine if the projection is at a threshold of the viewing plane, wherein the threshold relates to a length on the viewing plane;
- determine a boundary on the viewing plane when the projection is determined to be at the threshold such that the location of the boundary changes as a function of a change in the non-zero angle of incidence;
- and
- render on the viewing plane a projection of a first area of the map surface plane on one side of the boundary using a first density of map data and rendering a projection of a second area of the map surface plane on a second side of the boundary using a second density of map data lower than the first density of map data.
A computer device comprising:
- a communications network interface;
- one or more processors;
- one or more memories coupled to the one or more processors;
- a display device coupled to the one or more processors;
- wherein the one or more memories include computer executable instructions stored therein that, when executed by the one or more processors, cause the one or more processors to:
- determine a map surface plane and a viewing plane, wherein the viewing plane is at a non-zero angle of incidence with respect to the map surface plane;
- determine a first unit of area on the map surface plane, the first unit of area representing a map area viewed at a first zoom level through a pixel of the viewing plane when the viewing plane is at a zero angle of incidence with respect to the map surface plane, wherein the first unit of area has two dimensions along the map surface plane;
- determine a second unit of area on the map surface plane, the second unit of area representing a map area viewed at a second zoom level through a pixel of the viewing plane when the viewing plane is at a zero angle of incidence with respect to the map surface plane, wherein the second unit of area has two dimensions along the map surface plane;
- calculate a projection of a first dimension along the map surface plane of the first unit of area onto a first dimension along the viewing plane at the non-zero angle of incidence with respect to the map surface plane;
- determine if the projection is at a threshold of the viewing plane, wherein the threshold relates to a length on the viewing plane;
- determine a boundary on the viewing plane when the projection is determined to be at the threshold such that the location of the boundary changes as a function of a change in the non-zero angle of incidence;
- create an image containing a projection of the first unit of area of the map surface plane on one side of the boundary using a first density of map data and a projection of the second unit of area of the map surface plane on a second side of the boundary using a second density of map data lower than the first density of map data;
- and
- transmit the image of the projection of the map surface.
Dependencies are inferred from the claim text.