Free-form deformation
In computer graphics, free-form deformation (FFD) is a geometric technique used to model simple deformations of rigid objects. It is based on the idea of enclosing an object within a cube or another hull object, and transforming the object within the hull as the hull is deformed. Deformation of the hull is based on the concept of so-called hyper-patches, which are three-dimensional analogs of parametric curves such as Bézier curves, B-splines, or NURBs. The technique was first described by Thomas W. Sederberg and Scott R. Parry in 1986,[1] and is based on an earlier technique by Alan Barr.[2] It was extended by Coquillart to a technique described as extended free-form deformation, which refines the hull object by introducing additional geometry or by using different hull objects such as cylinders and prisms.[3]
Applications
- Free-Form Deformation is used in computer graphics for solid geometric models. For example, the Lattice Modifier in Blender (software).
- It is used in the image registration in both rigid and non-rigid transformation.
- It is also used in the detection process of breast cancer.[4]
References
- ↑ Sederberg, Thomas W.; Parry, Scott R. (1986). "Free-form deformation of solid geometric models". SIGGRAPH Computer Graphics (ACM) 20 (4): 151–160. doi:10.1145/15886.15903.
- ↑ Barr, A. H. (July 1984). "Global and local deformations of solid primitives". SIGGRAPH Computer Graphics 18 (3): 21–30. doi:10.1145/800031.808573.
- ↑ Coquillart, S. (September 1990). "Extended free-form deformation: a sculpturing tool for 3D geometric modeling". SIGGRAPH Computer Graphics (ACM) 24 (4): 187–196. doi:10.1145/97880.97900.
- ↑ Nonrigid Registration Using Free-Form Deformations: Application to Breast MR Images