Abstract: A method of scaling motion data input is provided in a system for interacting with objects, in a three-dimensional volume. The system includes a viewport onto which a two-dimensional image of the volume is displayed. A user provides motion input data to translate the volume or an object within the volume. A distance between a target and a portion of the viewport is calculated, and a scaling factor, based on the distance is calculated. The motion input data is incremented according to the scaling factor.