Patent ID: 7342580

Claim:
A computer implemented method for compressing a file of an animation model for an animation cycle comprising a plurality of frames of animation of the animation model, the model comprising an offset model including a plurality of surfaces, each surface including a plurality of vertices, the method comprising: predicting offset vertices of the offset model for corresponding reference vertices of a reference model for a first frame of the animation cycle and associated with the offset model, using basis coordinate systems respectively associated with the reference vertices; determining differences between the predicted offset vertices and actual offset vertices of the offset model for each subsequent frame of the animation cycle; and storing as a compressed file in a database the reference model and differences between the predicted offset vertices and actual offset vertices to allow reconstruction of the actual offset vertices using the reference vertices and the differences for each subsequent frame of the animation cycle; wherein at least one basis coordinate system comprises a triangle defined by the vertices P i,k−1 , P i+1,k−1 , P i+1,k−2 where the reference vertex is P i,k , and is in an odd row of the surface, each vertex being a coordinate in (x,y,z) in local space of the reference model, i and k being respectively the row and column of a matrix of the vertices.