Thomas Sederberg

Last updated

Thomas W. Sederberg is the associate dean of the college of physcial and mathematical sciences and professor of Computer Science at Brigham Young University in Provo, Utah. His research involves computer graphics and computer aided design. He helped invent free-form deformation and T-splines. [1]

Brigham Young University private research university in Provo, Utah

Brigham Young University is a private research university located in Provo, Utah and owned by The Church of Jesus Christ of Latter-day Saints. The university is run under the auspices of its parent-organization, the Church Educational System (CES), and is classified among "Doctoral Universities: High Research Activity" with "more selective, lower transfer-in" admissions. The university's primary emphasis is on undergraduate education in 179 majors, but it also has 62 master's and 26 doctoral degree programs. The university also administers two satellite campuses, one in Jerusalem and one in Salt Lake City.

Provo, Utah City in Utah, United States

Provo is the third-largest city in Utah, United States. It is 43 miles (69 km) south of Salt Lake City along the Wasatch Front. Provo is the largest city and county seat of Utah County.

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, and is based on an earlier technique by Alan Barr. 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.


Education and career

Sederberg studied civil engineering at Brigham Young University for both his Bachelor's (1975) and his Master's (1977) degrees. [2] Sederberg received his PhD from Purdue and joined the civil engineering faculty at BYU in 1983. [1] His PhD thesis discussed how to compute intersecting Bézier curves. [3]

He is an associate editor for ACM Transactions on Graphics [4] and for Computer Aided Geometric Design. [5]

ACM Transactions on Graphics (TOG) is a bimonthly peer-reviewed scientific journal that covers the field of computer graphics. It was established in 1982 and is published by the Association for Computing Machinery. TOG publishes two special issues for ACM SIGGRAPH's conference proceedings. Starting in 2003, all papers accepted for presentation at the annual SIGGRAPH conference are printed in a special summer issue of the journal. Beginning in 2008, papers presented at SIGGRAPH Asia are printed in a special November/December issue.

Sederberg co-founded T-Splines, inc. in 2004, which was acquired by Autodesk in 2011. [6]

Autodesk, Inc. is an American multinational software corporation that makes software services for the architecture, engineering, construction, manufacturing, media, education, and entertainment industries. Autodesk is headquartered in San Rafael, California, and features a gallery of its customers' work in its San Francisco building. The company has offices worldwide. Its U.S. locations are Northern California, Oregon, Colorado, Texas, Michigan, New England, New Hampshire and Massachusetts. Its Canada offices are located in Ontario, Quebec, and Alberta.


SIGGRAPH awarded Sederberg with the Computer Graphics Achievement award in 2006. [7] In 2013 Sederberg received the Pierre Bézier award for his contributions to solid modeling. [3]

SIGGRAPH conference series

SIGGRAPH is an annual conference on computer graphics (CG) organized by the ACM SIGGRAPH, starting in 1974. The main conference is held in North America; SIGGRAPH Asia, a second yearly conference, has been held since 2008 in countries throughout Asia.

Pierre Étienne Bézier was a French engineer and one of the founders of the fields of solid, geometric and physical modelling as well as in the field of representing curves, especially in CAD/CAM systems. As an engineer at Renault, he became a leader in the transformation of design and manufacturing, through mathematics and computing tools, into computer-aided design and three-dimensional modeling.

Purdue gave Sederberg the Outstanding Mechanical Engineer Award in 2014. [2] Brigham Young University awarded him the Steven V. White University Professorship, the Technology Transfer Award and the Distinguished Faculty Lecturer Award. [8] His publications are highly cited—in 2014 Thomson Reuters named Sederberg as one of the 108 most-cited professors in computer science. [1]

Personal life

Sederberg married Brenda Clark in 1978, and they had eight children. In 1995 Brenda was diagnosed with multiple sclerosis, and she died in 2012. [9]

See also

Related Research Articles

Bézier curve Curve used in computer graphics and related fields

A Bézier curve is a parametric curve used in computer graphics and related fields. The curve, which is related to the Bernstein polynomial, is named after Pierre Bézier, who used it in the 1960s for designing curves for the bodywork of Renault cars. Other uses include the design of computer fonts and animation. Bézier curves can be combined to form a Bézier spline, or generalized to higher dimensions to form Bézier surfaces. The Bézier triangle is a special case of the latter.

Computer-aided design Constructing a product by means of computer

Computer-aided design (CAD) is the use of computers to aid in the creation, modification, analysis, or optimization of a design. CAD software is used to increase the productivity of the designer, improve the quality of design, improve communications through documentation, and to create a database for manufacturing. CAD output is often in the form of electronic files for print, machining, or other manufacturing operations. The term CADD is also used.

Computational geometry is a branch of computer science devoted to the study of algorithms which can be stated in terms of geometry. Some purely geometrical problems arise out of the study of computational geometric algorithms, and such problems are also considered to be part of computational geometry. While modern computational geometry is a recent development, it is one of the oldest fields of computing with history stretching back to antiquity.

Composite Bézier curve

In geometric modelling and in computer graphics, a composite Bézier curve is a piecewise Bézier curve that is at least continuous. In other words, a composite Bézier curve is a series of Bézier curves joined end to end where the last point of one curve coincides with the starting point of the next curve. Depending on the application, additional smoothness requirements may be added.

Utah teapot model

The Utah teapot, or the Newell teapot, is a 3D test model that has become a standard reference object and an in-joke within the computer graphics community. It is a mathematical model of an ordinary teapot that appears solid, cylindrical, and partially convex. A teapot primitive is considered the equivalent of a "Hello, World" program, as a way to create an easy 3D scene with a somewhat complex model acting as a basic geometry reference for scene and light setup. Some programming libraries, such as the OpenGL Utility Toolkit, even have functions dedicated to drawing teapots.

Paul de Casteljau is a French physicist and mathematician. In 1959, while working at Citroën, he developed an algorithm for evaluating calculations on a certain family of curves, which would later be formalized and popularized by engineer Pierre Bézier, and the curves called De Casteljau curve or Bézier curves. De Casteljau's algorithm is widely used, with some modifications, as it is the most robust and numerically stable method for evaluating polynomials. Other methods, such as Horner's method and forward differencing, are faster for calculating single points but are less robust. De Casteljau's algorithm is still very fast for subdividing a De Casteljau curve or Bézier curve into two curve segments at an arbitrary parametric location.

Rhinoceros 3D 3D computer graphics software

Rhinoceros is a commercial 3D computer graphics and computer-aided design (CAD) application software developed by Robert McNeel & Associates, an American, privately held, employee-owned company founded in 1980. Rhinoceros geometry is based on the NURBS mathematical model, which focuses on producing mathematically precise representation of curves and freeform surfaces in computer graphics.

Jos Stam Dutch computer scientist

Jos Stam is a researcher in the field of computer graphics, focusing on the simulation of natural physical phenomena for 3D-computer animation. He achieved technical breakthroughs with the simulation of fluids and gases, new rendering algorithms and subdivision surfaces, which are a mix between two previously incompatible worlds of Nurbs- and polygon-modeling in 3D.

In computer-aided geometric design a control point is a member of a set of points used to determine the shape of a spline curve or, more generally, a surface or higher-dimensional object.

Geometric design branch of computational geometry

Geometric design (GD) is a branch of computational geometry. It deals with the construction and representation of free-form curves, surfaces, or volumes and is closely related to geometric modeling. Core problems are curve and surface modelling and representation. GD studies especially the construction and manipulation of curves and surfaces given by a set of points using polynomial, rational, piecewise polynomial, or piecewise rational methods. The most important instruments here are parametric curves and parametric surfaces, such as Bézier curves, spline curves and surfaces. An important non-parametric approach is the level-set method.

Chandrajit Bajaj is an American computer scientist. He is a Professor of Computer science at the University of Texas at Austin holding the Computational Applied Mathematics Chair in Visualization and is the director of the Computational Visualization Center, in the Institute for Computational Engineering and Sciences (ICES).

A T-spline surface can be thought of as a NURBS surface for which a row of control points is allowed to terminate without traversing the entire surface. The control net at a terminated row resembles the letter "T". Modeling surfaces with T-splines can reduce the number of control points in comparison to NURBS surfaces and make pieces easier to merge, but increases the book-keeping effort to keep track of the irregular connectivity. T-splines can be converted into NURBS surfaces, by knot insertion, and NURBS can be represented as T-splines without T's or by removing knots. T-splines can therefore, in theory, do everything that NURBS can do. In practice, enormous amount of programming was required to make NURBS work as well as they do, and creating the equivalent T-Spline functionality would require similar effort. To smoothly join at points where more than three surface pieces meet, T-splines have been combined with geometrically continuous constructions of degree 3 by 3 (bi-cubic) and, more recently, of degree 4 by 4 (bi-quartic).

Solid Modeling Solutions is a company who has an implementation of a mathematical representation of NURBS, 3D geometry, and Solid modeling technology which emerged in the 1980s and 1990s into a commercial implementation known as SMLib. This article will provide the background and history of this implementation into a commercial product line from Solid Modeling Solutions™ (SMS). SMS is an independent supplier of source code for a powerful suite of 3D geometry kernels. SMS provides advanced NURBS-based geometry libraries, SMLib™, TSNLib™, GSNLib™, NLib™, SDLib™, VSLib™, and PolyMLib™, that encompass extensive definition and manipulation of NURBS curves and surfaces with the latest fully functional non-manifold topology.

Shape Data Limited is a computer software company in Cambridge, England that specialises in developing programs for engineering and manufacturing professionals.

Ronald Neil Goldman is a Professor of Computer Science at Rice University in Houston, Texas. Professor Goldman received his B.S. in Mathematics from the Massachusetts Institute of Technology in 1968 and his M.A. and Ph.D. in Mathematics from Johns Hopkins University in 1973.

Dan R. Olsen Jr. is an American computer scientist who specialized in the fields of human–computer interaction and information science. He worked in the computer science department of Brigham Young University from 1984 until his retirement in 2015, serving as chair of the department (1992–96), and also directed the Human-Computer Interaction Institute at Carnegie Mellon University (1996–98).

Elaine Cohen is an American researcher in geometric modeling and computer graphics, known for her pioneering research on B-splines. She is a professor in the school of computing at the University of Utah.

Designers have used computers for calculations since their invention. Digital computers were used in power system analysis or optimization as early as proto-"Whirlwind" in 1949. Circuit design theory or power network methodology was algebraic, symbolic, and often vector-based.


  1. 1 2 3 "Dr. Sederberg earns distinction of being "Highly Cited"". BYU Computer Science. BYU. Archived from the original on November 9, 2017. Retrieved February 22, 2016.
  2. 1 2 "Thomas W. Sederberg". Purdue University Mechanical Engineering. Purdue University. 2014. Archived from the original on March 6, 2016. Retrieved February 24, 2016.
  3. 1 2 "Thomas W. Sederberg, the 2013 Pierre Bézier Award Recipient". Solid Modeling Association. Solid Modeling Association. Archived from the original on March 4, 2016. Retrieved February 24, 2016.
  4. "ACM Graphics Editorial Board". ACM Digital Library. ACM. Archived from the original on March 3, 2016. Retrieved February 22, 2016.
  5. "Computer Aided Geometric Design Editorial Board". Elsevier. Archived from the original on March 5, 2016. Retrieved February 22, 2016.
  6. Hadfield, Joe. "BYU prof's design technology acquired by software giant Autodesk". BYU News. BYU. Archived from the original on March 10, 2016. Retrieved February 22, 2016.
  7. "Awards". ACMSIGGRAPH. ACMSIGGRAPH. Archived from the original on March 2, 2016. Retrieved February 24, 2016.
  8. Holligshead, Todd (December 2, 2014). "BYU professors receive prestigious awards from Purdue University". BYU News. Archived from the original on March 10, 2016. Retrieved February 24, 2016.
  9. "Brenda Clark Sederberg". Deseret News. September 5, 2012. Archived from the original on March 3, 2016. Retrieved February 24, 2016.