When display devices are physically separated, have different orientations, or different sizes, techniques should be employed to help the user keep track of the cursor's position.
Additional Information:
When display devices are physically separated or dissimilar the cursor motion between them may not be perceptually smooth. That is, the user must translate motion on one display into a different motion in the other or follow the cursor as it 'jumps' across the space separating the displays. These factors may cause the user to lose track of the cursor's location. Various techniques can be used to support the user in following the cursor motion between display screens. The cursor can be made to always enter the other display at a uniquely specified entry point. This method allows the user to anticipate the cursor's location on the other display, which may reduce the time associated with finding it. However, the user must first locate the specified entry point. When display screens have different proportions of height and width, then the user may have difficulty understanding how the cursor position on the edge of one display screen corresponds to a position on the other screen. In such cases, computational techniques can be applied that compensate for the differences in screen sizes to make cursor motion appear more continuous. Alternatively, the small-screen display might overlap a smaller portion of the large-screen display, such that a one-to-one relationship in cursor motion is maintained.