Method and system for rendering of labels

1. A method of rendering static labels in a mobile device, comprising:

receiving panning increments for panning a previously rendered frame to a panned frame;

defining a rendering region based on the panning increments;

determining ones of the labels that overlap the rendering region;

rendering geometry that overlaps the rendering region;

copying a portion of the previously rendered frame;

comparing, for each of the ones of the labels, the amount of overlap, with the panned frame, to a threshold amount; and

rendering the ones of the labels that overlap with the panned frame by the threshold amount to provide the panned frame.

2. The method according to claim 1 , wherein the panning increments comprise horizontal and vertical panning increments.

3. The method according to claim 2 , wherein defining the rendering region comprises determining an L-shaped region having inner horizontal and vertical boundaries collinear with respective horizontal and vertical boundaries of the previously rendered frame and outer boundaries collinear with respective horizontal and vertical boundaries of the panned frame.

4. The method according to claim 1 , comprising determining screen space for each label prior to determining ones of the labels that overlap.

5. The method according to claim 4 , wherein determining screen space for each label comprises determining placement of the label on a respective path by determining placement of individual characters of each label along the respective path.

6. The method according to claim 5 , wherein said path is a line segment.

7. The method according to claim 5 , wherein said path is a polyline path comprising a sequence of line segments, wherein each pair of consecutive line segments is connected by a respective join point in the polyline path.

8. The method according to claim 5 , comprising, for each label, computing, prior to comparing, a respective bounding rectangle in which said respective screen space for the label is contained.

9. The method according to claim 8 , wherein computing the respective bounding rectangle comprises computing a rectangle that includes each of the first character of the label, the last character of the label, and each join point in the polyline path.

10. The method according to claim 9 , wherein comparing comprises ascertaining ones of the labels for which the area of the overlap of the respective bounding rectangle with the panned frame meets a threshold percentage of the area of the respective bounding rectangle.

11. The method according to claim 10 , wherein ascertaining ones of the labels comprises computing a percentage area of overlap of the respective bounding rectangle with the panned frame and comparing the computed percentage area of overlap to the threshold percentage.

12. A mobile device comprising a rendering engine for performing the method of claim 1 .

13. A computer readable device having computer-readable code embodied therein, the computer-readable code executable by at least one processor at a computing device to cause the electronic device to:

receive panning increments for panning a previously rendered frame to a panned frame;

define a rendering region based on the panning increments;

determine ones of the labels that overlap the rendering region;

render geometry that overlaps the rendering region;

copy a portion of the previously rendered frame;

compare, for each of the ones of the labels, the amount of overlap, with the panned frame, to a threshold amount; and

render the ones of the labels that overlap with the panned frame by a threshold amount to provide the panned frame.