Page 208 - Geometric Modeling and Algebraic Geometry
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11 Subdivision Methods for the Topology of 2d and 3d Implicit Curves  211























                                      (a) ridge curve               (b) self-intersection curve

                                       Fig. 11.1. Topological descriptions of high complexity curves


                              g(x)= x + y + z − 2
                                          2
                                      2
                                              2
                              time: 20 msec
                           3) f(x)=2x + y + z − 4
                                       2
                                           2
                                               2
                              g(x)= x +2xy + y − 2yz − 2z +2zx
                                                          2
                                                2
                                      2
                              time: 30 msec
                           4) f(x)= x + y +2x y +2x +2y − x − y − z
                                      4
                                                2 2
                                                            2
                                                       2
                                          4
                              g(x)= x +2x y + y +3x y − y + z    2
                                                 4
                                                       2
                                                            3
                                      4
                                           2 2
                              time: 130 msec
                              (a) Example 1    (b) Example 2    (c) Example 3    (d) Example 4
                           Fig. 11.2. Topological descriptions of the intersection curve for 4 pairs of low-order algebraic
                           surfaces.
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