User interface for controlling three-dimensional animation of an object

Abstract

A user can control the animation of an object via an interface that includes a control area and a user-manipulable control element. The control area includes an ellipse. The user-manipulable control element includes a three-dimensional arrow with a straight body, a three-dimensional arrow with a curved body, or a sphere. In one embodiment, the interface includes a virtual trackball that is used to manipulate the user-manipulable control element.

What is claimed is: 
     
         1 . A method for animating an object according to a speed with which the object moves and a direction in which the object moves, the method comprising:
 displaying a user interface comprising:
 a control area comprising an ellipse and a slider; 
 a representation of a three-dimensional vector having a variable orientation that specifies the direction, wherein the vector representation is located mostly within the ellipse; 
 a first user-manipulable control element that comprises a virtual trackball, wherein the first user-manipulable control element is located within the ellipse; and 
 a second user-manipulable control element that specifies the speed, wherein the second user-manipulable control element is located along the slider; 
   receiving a first input via the first user-manipulable control element, the first input comprising mousing down within the virtual trackball and continuing to mouse down for a period of time;   responsive to receiving the first input, displaying during the period of time a spherical mesh that represents the virtual trackball;   receiving a second input via the first user-manipulable control element, the second input comprising spinning the virtual trackball to change the orientation of the vector representation while continuing to mouse down within the virtual trackball;   receiving a third input via the first user-manipulable control element, the third input comprising mousing up;   responsive to receiving the third input, removing the spherical mesh from display;   receiving input via the second user-manipulable control element, the input comprising dragging the second user-manipulable control element to set the speed; and   animating the object based on the received input.