A scanline algorithm for displaying trimmed surfaces by using Bézier clipping

Tomoyuki Nishita; Kazufumi Kaneda; Eihachiro Nakamae

doi:10.1007/bf01905692

Triangulation of trimmed surfaces in parametric space

Computer-Aided Design ◽

10.1016/0010-4485(92)90011-x ◽

1992 ◽

Vol 24 (8) ◽

pp. 437-444 ◽

Cited By ~ 85

Author(s):

X. Sheng ◽

B.E. Hirsch

Keyword(s):

Parametric Space ◽

Trimmed Surfaces

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Approximate Degree Reduction of NURBS Curves and Surfaces: An Integrated Approach

4th Flexible Assembly Conference ◽

10.1115/detc1994-0368 ◽

1994 ◽

Author(s):

Srinivasa P. Varanasi ◽

Athamaram H. Soni

Keyword(s):

Shape Control ◽

Data Exchange ◽

Data Transfer ◽

Integrated Approach ◽

Free Form ◽

Aircraft Industry ◽

Trimmed Surfaces ◽

Curves And Surfaces ◽

High Degree ◽

Boundary Curves

Abstract Data exchange between different CAD systems usually requires conversion between different representations of free-form curves and surfaces. Also, trimmed surfaces give rise to high degree boundary curves. Accurate conversion of these forms becomes necessary for reliable data transfer. Also important is the issue of shape control, specially in the aircraft industry. The objective of this paper is to investigate conversion methods and effect of shape control on the design and choice of such methods.

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MATEC Web of Conferences – General and efficient algorithms for handling intricate situations in trimmed surface rendering

MATEC Web of Conferences ◽

10.1051/matecconf/201817503067 ◽

2018 ◽

Vol 175 ◽

pp. 03067

Author(s):

Luo Bo ◽

Gang Zhao ◽

Wei Wang ◽

Xiaoxiao Du

Keyword(s):

Efficient Algorithm ◽

Engineering Industry ◽

Free Form ◽

Surface Rendering ◽

Trimmed Surfaces ◽

Surface Models ◽

Practical Engineering ◽

Cad Cam ◽

Trimmed Surface ◽

Free Form Surface

Trimmed surfaces have been widely used in complicated product design in mechanical engineering especially in complex free form surface models of CAD/CAM/CAE. Focusing on the deficiencies of the algorithms available in published literatures when handling some intricate situations, this paper proposes a more general and efficient algorithm of trimmed surface rendering (ATSR). The ATSR is a general algorithm that can deal with most intricate situations, which frequently occur in practical engineering that no special attention has been paid to in references at hand, as well as common situations. Furthermore, this paper presents a new algorithm for the nodes of polygon connecting into elements (ANCE). The ANCE can handle most tricky polygons appearing in the process of rendering and achieve successful triangulation for the to-be-rendered surface. Preferable results are obtained in the case studies, which indicate that the algorithms (ATSR and ANCE) are efficient and effective in handling complicated as well as common trimmed surface models in real engineering industry.

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The algorithms for trimmed surfaces construction and tool path generation in reverse engineering

Computers & Industrial Engineering ◽

10.1016/j.cie.2007.09.012 ◽

2008 ◽

Vol 54 (3) ◽

pp. 624-633 ◽

Cited By ~ 7

Author(s):

Y.H. Peng ◽

Z.W. Yin

Keyword(s):

Reverse Engineering ◽

Tool Path ◽

Tool Path Generation ◽

Path Generation ◽

Trimmed Surfaces

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Reconstruction of Trimmed NURBS Surfaces for Gap-Free Intersections

Journal of Computing and Information Science in Engineering ◽

10.1115/1.4047427 ◽

2020 ◽

Vol 20 (5) ◽

Author(s):

Benjamin Urick ◽

Richard H. Crawford ◽

Thomas J. R. Hughes ◽

Elaine Cohen ◽

Richard F. Riesenfeld

Keyword(s):

Computer Aided Design ◽

Engineering Practice ◽

Global Parameter ◽

Trimmed Surfaces ◽

File Formats ◽

Modern Engineering ◽

Computer Aided ◽

Step Algorithm ◽

Aided Design ◽

User Knowledge

Abstract The modern engineering technologies of computer-aided design (CAD), computer-aided engineering (CAE), and computer-aided manufacturing (CAM) are ubiquitous in engineering practice. They are focused on creating, analyzing, and fabricating engineering artifacts represented as geometric models. Historically, these technologies developed independently, with different geometric representations that are customized to the needs of the technology. As a result, the combined use of these technologies has led to differences in data structures, file formats, and user knowledge and practice, requiring translation of representations between systems to support interoperability. Complicating this situation is the approximate nature of modeling operations in CAD systems, which can result in gaps at the boundary curves between mating trimmed surfaces of a model. The research presented here is aimed at removing the gaps between trimmed surfaces, resulting in a “watertight” model that is suitable for use directly by downstream applications. A three-step algorithm is presented that includes analysis of the parametric space of the trimming curves, reparameterization to create a global parameter space, and reconstruction of the intersecting surfaces to ensure continuity at the trimming curve.

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