You-Dong Liang () is a

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

and

educator A teacher, also called a schoolteacher or formally an educator, is a person who helps students to acquire knowledge, competence, or virtue, via the practice of teaching. ''Informally'' the role of teacher may be taken on by anyone (e.g. w ...

, best known for his contributions in

geometric modeling __NOTOC__ Geometric modeling is a branch of applied mathematics and computational geometry that studies methods and algorithms for the mathematical description of shapes. The shapes studied in geometric modeling are mostly two- or three-dimensi ...

and the Liang-Barsky algorithm.

Education and teaching

You-Dong Liang was born on July 19, 1935, in

Fuzhou Fuzhou is the capital of Fujian, China. The city lies between the Min River (Fujian), Min River estuary to the south and the city of Ningde to the north. Together, Fuzhou and Ningde make up the Eastern Min, Mindong linguistic and cultural regi ...

Fujian Province Fujian is a province in southeastern China. Fujian is bordered by Zhejiang to the north, Jiangxi to the west, Guangdong to the south, and the Taiwan Strait to the east. Its capital is Fuzhou and its largest prefecture city by population is Qua ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

. Liang pursued his graduate degree in

Fudan University Fudan University (FDU) is a public university, national public university in Yangpu, Shanghai, Yangpu, Shanghai, China. It is affiliated with the Ministry of Education (China), Ministry of Education and is co-funded with the Shanghai Municipal ...

, where he worked under the supervision of Professor Su Buqing and specialized in geometric theory. After graduating in 1960, he joined the mathematics teaching faculty at

Zhejiang University Zhejiang University (ZJU) is a public university, public research university in Hangzhou, Zhejiang, China. It is affiliated with the Ministry of Education (China), Ministry of Education. The university is part of Project 211, Project 985, and D ...

, where he actively promoted the development of geometric design and graphics. From 1984–1990, he was the chairman of the mathematics department, and on several occasions, was a visiting scholar and visiting professor at the

University of California at Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California), is a public land-grant research university in Berkeley, California, United States. Founded in 1868 and named after the Anglo-Irish philosopher George Berkele ...

University of Utah The University of Utah (the U, U of U, or simply Utah) is a public university, public research university in Salt Lake City, Utah, United States. It was established in 1850 as the University of Deseret (Book of Mormon), Deseret by the General A ...

, and

University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...

. Liang helped form the Computational Geometry Collaborative Group in China. As the leader of this group, Liang supported the collaboration of scholars in

geometric design Geometrical 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 modelli ...

and computational graphics. Liang was awarded the “Chinese Geometric Design and Calculation Contribution Award” in 2009.

Contributions, papers, and awards

Liang has worked on computer-aided geometric design and computer graphics research. In 1984, Liang developed the

Liang–Barsky algorithm In computer graphics, the Liang–Barsky algorithm (named after You-Dong Liang and Brian A. Barsky) is a line clipping algorithm. The Liang–Barsky algorithm uses the parametric equation of a line and inequalities describing the range of the clip ...

, which has applications in computer graphics. Liang made further improvements on this algorithm in 1992.Liang, YD, and Barsky, B., "A New Concept and Method for Line Clipping", ACM Transactions on Graphics, 3 (1): 1–22, January 1984. In the late 1980s and early 1990s, Liang proposed a series of theories and methodologies in

geometric continuity In mathematical analysis, the smoothness of a function (mathematics), function is a property measured by the number of Continuous function, continuous Derivative (mathematics), derivatives (''differentiability class)'' it has over its Domain o ...

. In 1991, Liang supervised the completion of "Generated Computer Graphics and Geometric Modeling Research" and was awarded the Chinese National Science Third Prize. During these years, Liang received other honors, including the

Chinese Academy of Sciences The Chinese Academy of Sciences (CAS; ) is the national academy for natural sciences and the highest consultancy for science and technology of the People's Republic of China. It is the world's largest research organization, with 106 research i ...

Award and the “European Graphics Conference” Best Paper Award. Liang has published more than 50 papers, including "A New Concept and Method for Line Clipping", "Some Theorems on Geometrical Objects", "Curve and Surface Geometry Continuity", and "An Analysis and Algorithm for Polygon Clipping."

References

{{DEFAULTSORT:Liang, You-Dong Mathematicians from Fujian Chinese geometers 1935 births Living people University of Utah faculty People from Fuzhou Educators from Fujian 20th-century Chinese science writers Writers from Fuzhou