Directional Focus Navigation

Abstract

A rendering engine that supports directional focus navigation, in response to a directional input, shifts the focus to an appropriate focusable element. The rendering engine determines one or more focusable elements that are candidates to receive the focus based on the received directional input and based on the relative display locations of the focusable elements. The rendering engine selects the most appropriate candidate focusable element based on each candidate element's display location in relation to the display location of the element that currently has focus.

1 . A method executed via one or more processors on a client device, the method comprising:
 identifying a first element associated with a rendered document, the first element having focus;   receiving an indication of a directional input;   determining a display point of the first element corresponding to the directional input;   determining a display point of a second focusable element corresponding to the directional input;   calculating a first distance between the display point of the first element and the display point of the second focusable element; and   in an event the first distance is determined to be greater than a tolerance value, identifying the second focusable element as a candidate to receive focus in response to the directional input.   
     
     
         2 . A method as described in  claim 1 , further comprising:
 determining a display point of a third focusable element corresponding to the directional input;   calculating a second distance between the display point of the first element and the display point of the third focusable element; and   in an event the second distance is determined to be greater than the tolerance value, selecting one of the second focusable element or the third focusable element to receive focus in response to the directional input by comparing the first distance to the second distance.   
     
     
         3 . A method as described in  claim 1 , wherein the tolerance value is based on a width of the first element having focus and a width of the second focusable element. 
     
     
         4 . A method as described in  claim 1 , wherein the tolerance value is based on a height of the first element having focus and a height of the second focusable element. 
     
     
         5 . A method as described in  claim 1 , wherein at least the first element or the second focusable element is not a symmetrical shape. 
     
     
         6 . A method as described in  claim 1 , wherein at least the first element or the second focusable element is an arbitrary shape. 
     
     
         7 . A method as described in  claim 1 , wherein the display point of the first element is a representative horizontal coordinate, determined by averaging a plurality of horizontal coordinates of the first element. 
     
     
         8 . A method as described in  claim 1 , wherein the display point of the first element is a representative vertical coordinate, determined by averaging a plurality of vertical coordinates of the first element. 
     
     
         9 . A method as described in  claim 1 , wherein the display point of the first element comprises:
 an average vertical coordinate of the first element; and   an average horizontal coordinate of the first element.   
     
     
         10 . A method as described in  claim 1 , wherein:
 the display point of the first element represents a midpoint of the first element; and   the display point of the second focusable element represents a midpoint of the second focusable element.   
     
     
         11 . One or more computer storage media storing instructions that, when executed by the one or more processors, direct a computing device to perform operations comprising:
 determining a first element that currently has focus;   determining a display point for the first element;   receiving a directional input;   identifying, based at least in part on the directional input, a second element as a candidate element for moving focus from the first element;   determining a display point for the second element;   calculating a distance between the display point for the first element and the display point for the second element; and   in an event the distance is greater than a tolerance value, moving focus from the first element to the second element in response to receiving the directional input.   
     
     
         12 . One or more computer storage media as described in  claim 11 , wherein the distance is a first distance, and further storing instructions that, when executed by the one or more processors, direct the computing device to perform operations comprising:
 identifying, based at least in part on the directional input, a third element as another candidate element for moving focus from the first element;   determining a display point for the third element;   calculating a second distance between the display point for the first element and the display point for the third element; and   in an event the second distance is greater than the tolerance value, selecting one of the second element or the third element to receive focus from the first element in response to the directional input by comparing the first distance to the second distance.   
     
     
         13 . One or more computer storage media as described in  claim 11 , wherein the tolerance value is a difference calculated by subtracting a width of the first element from a width of the second element. 
     
     
         14 . One or more computer storage media as described in  claim 11 , wherein the tolerance value is a difference calculated by subtracting a height of the first element from a height of the second element. 
     
     
         15 . One or more computer storage media as described in  claim 11 , wherein at least the first element or the second element is not a symmetrical shape. 
     
     
         16 . One or more computer storage media as described in  claim 11 , wherein at least the first element or the second element is an arbitrary shape. 
     
     
         17 . One or more computer storage media as described in  claim 11 , wherein the display point for the first element is a representative horizontal coordinate, determined by averaging a plurality of horizontal coordinates of the first element. 
     
     
         18 . One or more computer storage media as described in  claim 11 , wherein the display point for the first element is a representative vertical coordinate, determined by averaging a plurality of vertical coordinates of the first element. 
     
     
         19 . One or more computer storage media as described in  claim 11 , wherein the display point for the first element comprises:
 an average vertical coordinate of the first element; and   an average horizontal coordinate of the first element.   
     
     
         20 . One or more computer storage media as described in  claim 11 , wherein:
 the display point for the first element represents a midpoint of the first element; and   the display point for the second element represents a midpoint of the second element.