CONSTRAINING DISPLAY MOTION IN DISPLAY NAVIGATION

1 . A method comprising:

superimposing a viewing window on a page of information, wherein:

the page of information is larger than the viewing window; and

the viewing window reveals only a subset of the page of information;

moving the viewing window relative to the page of information in response to a user's manipulation of an input tool;

tracking a motion of the input tool when moving the viewing window relative to the page of information;

comparing the motion of the input tool to a threshold;

determining whether the motion of the input tool exceeds the threshold; and

snapping back the viewing window to an original position if it is determined that the motion of the input tool does not exceed the threshold.

2 . The method of claim 1 wherein:

tracking the motion of the input tool includes tracking a horizontal motion of the input tool;

comparing the motion of the input tool to the threshold includes comparing the horizontal motion of the input tool to the threshold;

determining whether the motion of the input tool exceeds the threshold includes determining whether the horizontal motion of the input tool exceeds the threshold; and

snapping back the viewing window to the original position includes snapping back the viewing window to an original horizontal position if it is determined that the horizontal motion of the input tool does not exceed the threshold.

3 . The method of claim 2 further comprising leaving a vertical position of the viewing window unchanged.

4 . The method of claim 1 wherein:

tracking the motion of the input tool includes tracking a vertical motion of the input tool;

comparing the motion of the input tool to the threshold includes comparing the vertical motion of the input tool to the threshold;

determining whether the motion of the input tool exceeds the threshold includes determining whether the vertical motion of the input tool exceeds the threshold; and

snapping back the viewing window to the original position includes snapping back the viewing window to an original vertical position if it is determined that the vertical motion of the input tool does not exceed the threshold.

5 . The method of claim 4 further comprising leaving a horizontal position of the viewing window unchanged.

6 . The method of claim 1 wherein comparing the motion of the input tool to the threshold includes comparing the motion of the input tool to a user-defined threshold.

7 . The method of claim 1 wherein comparing the motion of the input tool to the threshold includes comparing the motion of the input tool to a system-defined threshold.

8 . The method of claim 1 wherein the page of information includes at least one column of information and snapping back the viewing window to the original position includes snapping back the viewing window to the at least one column of information if it is determined that the motion of the input tool does not exceed the threshold.

9 . The method of claim 1 wherein tracking the motion of the input tool further includes:

determining that the input tool has been activated by the user, wherein the activation of the input tool suggests an intent of relating the motion of the input tool to the motion of the viewing window;

in response to the activation of the input tool, tracking the motion of the input tool.

10 . The method of claim 9 further comprising terminating the tracking of the motion of the input tool upon determining that the input tool has been deactivated, wherein the deactivation of the input tool suggests and intent of ending the relationship between the motion of the input tool and the viewing window.

11 . The method of claim 10 further comprising determining a position of the input tool at the time of the input tool is deactivated and wherein comparing the motion of the input tool to the threshold includes comparing the position of the input tool to the threshold.

12 . The method of claim 11 wherein:

determining whether the motion of the input tool exceeds the threshold includes determining whether the position of the input tool exceeds the threshold; and

snapping back the viewing window to the original position includes snapping back the viewing window to the original position if it is determined that the position of the input tool does not exceed the threshold.