Area-Construction Algorithms Using Tangent Circles


  • Ching-Shoei Chiang Computer Science and Information Management, Soochow University, Taipei, Taiwan
  • Hung-Chieh Li Computer Science and Information Management, Soochow University, Taipei, Taiwan



medial-axis transform, hermite curve, bezier curve, computer-aided geometric design


Computer aided geometric design employs mathematical and computational methods for describing geometric objects, such as curves, areas in two dimensions (2D) and surfaces, and solids in 3D. An area can be represented using its boundary curves, and a solid can be represented using its boundary surfaces with intersection curves among these boundary surfaces. In addition, other methods, such as the medial-axis transform, can also be used to represent an area. Although most researchers have presented algorithms that find the medial-axis transform from an area, a algorithm using the contrasting approach is proposed; i.e., it finds an area using a medial-axis transform. The medial-axis transform is constructed using discrete points on a curve and referred to as the skeleton of the area. Subsequently, using the aforementioned discrete points, medial-axis circles are generated and referred to as the muscles of the area. Finally, these medial-axis circles are blended and referred to as the blended boundary curves skin of the area; consequently, the boundary of the area generated is smooth.


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How to Cite

C.-S. Chiang and H.-C. Li, “Area-Construction Algorithms Using Tangent Circles”, Adv. technol. innov., vol. 5, no. 2, pp. 126–134, Apr. 2020.