This article presents a novel technique that combines eye-tracking with subtle image-space modulation to direct a viewer's gaze about a digital image. We call this paradigm subtle gaze direction . Subtle gaze direction exploits the fact that our peripheral vision has very poor acuity compared to our foveal vision. By presenting brief, subtle modulations to the peripheral regions of the field of view, the technique presented here draws the viewer's foveal vision to the modulated region. Additionally, by monitoring saccadic velocity and exploiting the visual phenomenon of saccadic masking, modulation is automatically terminated before the viewer's foveal vision enters the modulated region. Hence, the viewer is never actually allowed to scrutinize the stimuli that attracted her gaze. This new subtle gaze directing technique has potential application in many areas including large scale display systems, perceptually adaptive rendering, and complex visual search tasks.

We present a new screen space widget, the IBar, for effective camera control in 3D graphics environments. The IBar provides a compelling interface for controlling scene perspective based on the artistic concept of vanishing points. Various handles on the widget manipulate multiple camera parameters simultaneously to create a single perceived projection change. For example, changing just the perspective distortion is accomplished by simultaneously decreasing the camera's distance to the scene while increasing focal length. We demonstrate that the IBar is easier to learn for novice users and improves their understanding of camera perspective.