Directable cloth animation

A method for animating a three-dimensional (3D) character, the method being performed by one or more computer systems, the method comprising:

• receiving a plurality of frames representing an animation sequence of the 3D character, the 3D character having a piece of cloth thereon;
• dividing the piece of cloth into a set of vertices such that the piece of cloth may be animated through the set of vertices;
• displaying a frame of the plurality of frames on a display, the frame including the 3D character and the piece of cloth;
• receiving a user input including an arrow drawn on the display, the arrow indicating a direction of movement of at least a portion of the piece of cloth in the animation sequence, the user input specifying a total force to be applied to the piece of cloth during the animation sequence of the 3D character;
• generating the total force as specified by the user input for animating the piece of cloth during the animation sequence of the 3D character, wherein the generation of the total force comprises:
• sampling one or more points along the arrow;
• selecting one or more vertices on the piece of cloth based on the one or more points sampled;
• and
• for each selected vertex:
• determining, based on the user input and the arrow, a virtual force to be applied to the selected vertex during the animation sequence of the 3D character;
• and
• simulating, according to the virtual force for each selected vertex, an animation of the piece of cloth during the animation sequence of the 3D character.

A method for animating a 3D character, the method being performed by one or more computer systems, the method comprising:

• receiving a plurality of frames representing an animation sequence of the 3D character, the 3D character having a piece of cloth thereon, the piece of cloth being dividable into a set of vertices such that the piece of cloth is animatable through the set of vertices;
• displaying a frame of the plurality of frames on a display, the frame including the 3D character and the piece of cloth;
• receiving a user input including a drawing of a silhouette stroke on the display with respect to the piece of cloth, the silhouette stroke indicating towards which at least a portion of the piece of cloth is to move during the animation sequence;
• generating virtual forces according to the silhouette stroke for animating the piece of cloth during the animation sequence, wherein the generation of the virtual forces comprises:
• selecting vertices on the piece of cloth based on distances of the vertices to the silhouette stroke;
• and
• for each selected vertex:
• determining a virtual force to be applied to the selected vertex based on a distance of the selected vertex to the silhouette stroke;
• and
• simulating, according to the generated virtual forces, an animation of the piece of cloth.

A computer product comprising a non-transitory computer readable medium storing a plurality of instructions that when executed control a computer system to animating a three-dimensional (3D) character, the instructions comprising:

• receiving a plurality of frames representing an animation sequence of the 3D character, the 3D character having a piece of cloth thereon;
• dividing the piece of cloth into a set of vertices such that the piece of cloth may be animated through the set of vertices;
• displaying a frame of the plurality of frames on a display, the frame including the 3D character and the piece of cloth;
• receiving a user input including a graphical indication on the display indicating a direction of movement of at least a portion of the piece of cloth in the animation sequence, the user input specifying a total force to be applied to the piece of cloth during the animation sequence of the 3D character;
• generating the total force as specified by the user input for animating the piece of cloth during the animation sequence of the 3D character, wherein the generation of the total force comprises:
• sampling one or more points according to the graphical indication;
• selecting, based on the one or more points sampled, one or more vertices on the piece of cloth for applying the total force as specified by the user input;
• and
• for each selected vertex:
• determining, based on the user input and the graphical indication, a virtual force to be applied to the selected vertex during the animation sequence of the 3D character;
• and
• simulating, according to the generated virtual force, an animation of the piece of cloth during the animation sequence of the 3D character.