Abstract: A method for animating fibers in a computer-based animation process, the method comprises: obtaining a fiber cache comprising a plurality of fibers, each of the plurality of fibers comprising a plurality of fiber vertices; obtaining one or more guides, each of the one or more guides comprising a plurality guide vertices; and determining binding information to bind the one or more guides to the fiber cache. Determining the binding information comprises, for each fiber of the fiber cache: associating the fiber with one or more nearby guides; and, for each of the one or more associated nearby guides: associating each fiber vertex with a nearby guide vertex; and determining, for each fiber vertex, a displacement vector between the fiber vertex and the associated nearby guide vertex.

Abstract: A method for manipulating vertex positions of one or more simulated hair strands based on user input while preserving shape details of the one or more simulated hair strands. The method comprises receiving a displacement vector and a region as input and identifying first consecutive groups of vertices of a first simulated hair strand within the region. For each first consecutive group of vertices within the region, the method comprises finding the average vertex position, determining the closest vertex of the consecutive group of vertices to the average vertex position, determining a new positional constraint based on the closest vertex and the displacement vector and determining new vertex positions for the first simulated hair strand by running a constraint enforcement process constrained by the new positional constraint for each consecutive group of vertices and one or more shape-preserving constraints.