Abstract
We present a mathematical theory of the two-dimensional offset curves from the viewpoint of medial axis transform. We explore the local geometry of the offset curve in relation with the medial axis transform, culminating in the classification of points on the offset curve. We then study the domain decomposition from the viewpoint of offsets, and in particular introduce the concept of monotonic fundamental domain as a device for detecting the correct topology of offsets as well as for stable numerical computation. The monotonic fundamental domains are joined by peaks or valleys of the medial axis transform, or by what we call the critical horizonal section whose algebro-geometric properties are rigorously treated as well.
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Ait-Haddou, R., Biard, L., Slawinski, M.A.: Minkowski isoperimetric-hodograph curves. Comput. Aided Geom. Design 17(9), 835–861 (2000)
Chiang, C.-S., Hoffmann, C.M., Lynch, R.E.: How to compute offsets without self-intersection. Technical Report CSD-TR-91-072. Computer Sciences Department, Purdue University (1991)
Choi, B.K., Park, S.C.: A pair-wise offset algorithm for 2d point-sequence curve. Comput.-Aided Des. 31(12), 735–745 (1999)
Choi, H.I., Choi, S.W., Moon, H.P.: Mathematical theory of medial axis tranform. Pacific J. Math. 181(1), 57–88 (1997)
Choi, H.I., Choi, S.W., Moon, H.P., Wee, N.-S.: New algorithm for medial axis transform of plane domain. Graph. Models Image Process. 59(6), 463–483 (1997)
Chou, J.J., Cohen, E.: Computing offsets and tool paths with Voronoi diagrams. Technical report. Department of Computer Science, University of Utah, Salt Lake City, UT (1990)
Chuang, S.H.F., Kao, C.Z.: One-sided arc approximation of b-spline curves for interference-free offsetting. Comput.-Aided Des. 31(2), 111–118 (1999)
Coquillart, S.: Computing offsets of B-spline curves. Comput.-Aided Des. 19(6), 305–309 (1987)
Elber, G., Lee, I.-K., Kim, M.-S.: Comparing offset curve approximation methods. IEEE Comput. Graph. Appl. 17(3), 62–71 (1997)
Farouki, R.T.: Conic approximation of conic offsets. J. Symbolic Comput. 23, 301–313 (1997)
Farouki, R.T., Neff, C.A.: Algebraic properties of plane offset curves. Comput. Aided Geom. Design 7, 101–127 (1990)
Farouki, R.T., Neff, C.A.: Analytic properties of plane offset curves. Comput. Aided Geom. Design 7, 83–99 (1990)
Farouki, R.T., Ramamurthy, R.: Specified-precision computation of curve/curve bisector. Technical Report UM-MEAM-96-10. Dept. of Mechanical Engineering and Applied Mechanics, University of Michigan, Ann Arbor, MI (1998)
Farouki, R.T., S.T.: Pythagorean hodographs. IBM J. Res. Develop. 34, 736–752 (1990)
Feng, H.-Y., Li, H.: Constant scallop-height tool path generation for three-axis sculptured surface machining. Comput.-Aided Des. 34(9), 647–654 (2002)
Glaeser, G., Wallner, J., Pottmann, H.: Collision-free 3-axis milling and selection of cutting tools. Comput.-Aided Des. 31(3), 225–232 (1999)
Held, M.: On the Computational Geometry of Pocket Machining. In: Lecture Notes in Computer Science, vol. 500. Springer, Berlin (1991)
Held, M., Lukács, G., Andor, L.: Pocket machining based on coutour-parallel tool paths generated by means of proximity maps. Comput.-Aided Des. 26(3), 189–203 (1994)
Holla, V.D., Shastry, K.G., Prakash, B.G.: Offset of curves on tessellated surfaces. Comput.-Aided Des. 35(12), 1099–1108 (2003)
Hon-Yuen Tam, H.-W.L., Xu, H.: A geometric approach to the offsetting of profiles on three-dimensional surfaces. Comput.-Aided Des. 36, 887–902 (2004)
Hoschek, J.: Offset curves in the plane. Comput. Aided Des. 17(2), 77–82 (1985)
Hoschek, J.: Spline approximation of offset curves. Comput. Aided Geom. Design 5, 33–40 (1988)
Hui, K.C.: Free-form design using axial curve-pairs. Comput.-Aided Des. 34(8), 583–595 (2002)
Jun, C.-S., Kim, D.-S., Park, S.: A new curve-based approach to polyhedral machining. Comput.-Aided Des. 34(5), 379–389 (2002)
Jüttler, B., Mäurer, C.: Cubic pythagorean hodograph spline curves and applications to sweep surface modeling. Comput.-Aided Des. 31(1), 73–83 (1999)
Klass, R.: An offset spline approximation for plane cubic splines. Comput. Aided Des. 15(5), 297–299 (1983)
Lartigue, C., Thiebaut, F., Maekawa, T.: Shapes with offsets of nearly constant surface area. Comput. Aided Des. 31(4, 1), 287–296 (1999)
Lartigue, C., Thiebaut, F., Maekawa, T.: Cnc tool path in terms of b-spline curves. Comput.-Aided Des. 33(4, 2), 307–319 (2001)
Lee, E.: Contour offset approach to spiral toolpath generation with constant scallop height. Comput.-Aided Des. 35(6), 511–518 (2003)
Lee, I.-K., Kim, M.-S., Elber, G. Planar curve offset based on circle approximation. Comput.-Aided Des. 28(8), 617–630 (1996)
Meek, D.S., Walton, D.J.: Offset curves of clothoidal splines. Comput.-Aided Des. 22(4), 199–201 (1990)
Park, S.C., Choi, B.K.: Uncut free pocketing tool-paths generation using pair-wise offset algorithm. Comput.-Aided Des. 33(10), 739–748 (2001)
Park, S.C., Chung, Y.C.: Offset tool-path linking for pocket machining. Comput.-Aided Des. 34(4), 299–308 (2002)
Park, S.C., Chung, Y.C., Choi, B.K.L: Contour-parallel offset machining without tool-retractions. Comput.-Aided Des. 35(9), 841–849 (2003)
Persson, H.: NC machining of arbitrarily shaped pockets. Comput.-Aided Des. 10(3), 169–174 (1978)
Pham, B.: Offset approximation of uniform B-splines. Comput.-Aided Des. 20(8), 471–474 (1988)
Pham, B.: Offset curves and surfaces: A brief survey. Comput.-Aided Des. 24(4), 223–229 (1992)
Piegl, L.A., Tiller, W.: Computing offsets of NURBS curves and surfaces1. Comput.-Aided Des. 31(2), 147–156 Feb (1999)
Pottmann, H.: Curve design with rational Pythagorean-hodograph curves. Adv. Comput. Math. 3, 147–170 (1995)
Pottmann, H.: Rational curves and surfaces with rational offsets. Comput. Aided Geom. Design 12(2), 175–192 Mar (1995)
Ravi Kumar, G.V.V., Shastry, K.G., Prakash, B.G.: Computing non-self-intersecting offsets of NURBS surfaces. Comput.-Aided Des. 34(3), 209–228 (2002)
Tiller, W., Hanson, E.G.: Offsets of two-dimensional profiles. IEEE Comput. Graph. Appl. 4, 36–46 (1984)
Wang, L.Z., Miura, K.T., Nakamae, E., Yamamoto, T., Wang, T.J.: An approximation approach of the clothoid curve defined in the interval [0, /2] and its offset by free-form curves. Comput.-Aided Des. 33(14), 1049–1058 (2001)
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Communicated by: R.T. Farouki.
First author holds joint appointment in the Research Institute of Mathematics, Seoul National University.
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Choi, H.I., Choi, S.W., Han, C.Y. et al. Two-dimensional offsets and medial axis transform. Adv Comput Math 28, 171–199 (2008). https://doi.org/10.1007/s10444-007-9036-5
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DOI: https://doi.org/10.1007/s10444-007-9036-5