Direct manipulation of free-form deformations

Fme-form defommtion (FFD) is apowerful modeting tool, butcontmtling the shape of an object under complex deformations isoften ~cult.‘fhe interface to FFD in most conventional syetemssimply mpmentsthe unddyingmathematics directly, ur3ent&-acdbe deformations by manipulating control points. lhe difEcultyin controlling shape precisely is largely due to the control pcdntebeing extmneous to the objec~ the deformed object does not followthe control pointn exactly. In addition, the number of &gmes offreedom pre@entedto the user cm be ovenvhelming. We present amethod that allows a uacrto control a fme-form deformation of anobject by manipulating the object dhectly, leading to better contmdof the deformation and a more intuitive interface