Fig. 1. Delaunay neighborhood

Fig. 2. Illustration of angle αpiformed between points

Fig. 3. Approximate geodesic distance computation. (a) 1-order Delaunay neighborhood; (b) 2-order Delaunay neighborhood

Fig. 4. Voronoi diagram

Fig. 5. Gradient flow field from p

Fig. 6. Feature extraction effect of FunckyCube model. (a) FunckyCube model; (b) feature points

Fig. 7. Feature extraction effect of Fandisk model. (a) Fandisk model; (b) feature points

Fig. 8. Feature extraction effect of Vase model. (a) Vase model; (b) feature points

Fig. 9. Feature extraction effect of RockerArm model. (a) RockerArm model; (b) feature points

Fig. 10. Feature extraction results of noisy models. (a)(c)(e)(g) Noise of 0.03 dB; (b)(d)(f)(h) noise of 0.05 dB

Fig. 11. Point cloud models of Terracotta debris. (a) No.1 Terracotta debris; (b) No.2 Terracotta debris

Fig. 12. Feature lines extracted by Park’s method. (a) Vase model; (b) RockerArm model; (c) No.1 Terracotta debris; (d) No.2 Terracotta debris

Fig. 13. Feature lines of Wang’s method. (a) Vase model; (b) RockerArm model; (c) No.1 Terracotta debris; (d) No.2 Terracotta debris

Fig. 14. Feature lines of proposed method. (a) Vase model; (b) RockerArm model; (c) No.1 Terracotta debris; (d) No.2 Terracotta debris

Fig. 15. Line-drawings of Terracotta debris. (a) No.3 Terracotta debris; (b) line-drawing of Fig. 15(a); (c) No.4 Terracotta debris; (d) line-drawing of Fig. 15(c); (e) No.5 Terracotta debris; (f) line-drawing of Fig. 15(e); (g) No.6 Terracotta debris; (h) line-drawing of Fig. 15(g)