modeling by drawing with shadow guidance

Modeling by Drawing with Shadow Guidance Lubin Fan 1 , Ruimin Wang 2 - PowerPoint PPT Presentation

Modeling by Drawing with Shadow Guidance Lubin Fan 1 , Ruimin Wang 2 , Linlin Xu 2 , Jiansong Deng 2 , Ligang Liu 2 1 Zhejiang University 2 University of Science and Technology of China 1 3D Modeling Fundamental problem Many


  1. Modeling by Drawing with Shadow Guidance Lubin Fan 1 , Ruimin Wang 2 , Linlin Xu 2 , Jiansong Deng 2 , Ligang Liu 2 1 Zhejiang University 2 University of Science and Technology of China 1

  2. 3D Modeling • Fundamental problem • Many professional modeling systems • Requiring skills and costing time • Too difficult for non-professional users! 2

  3. 3D Modeling • Easy-to-use systems Drawing sketch is a very natural way to express oneself. 3

  4. Sketch-based Modeling Systems [Rivers et al. 2010] [Igarashi et al. 1999] [Karpenko et al. 2006] Not easy to draw! 4

  5. Example-based Modeling System [Funkhouser et al. 2004] [Chaudhuri et al. 2011] [Jain et al. 2012] 5

  6. Hybrid Systems Sketch2Scene [Xu et al. 2013] Sketch-to-Design [Xie et al. 2013] 6

  7. Guidance Helpful! 7

  8. Shadow Guidance ShadowDraw [Lee et al. 2011] 8

  9. Shadow Guidance ShadowDraw [Lee et al. 2011] 9

  10. Goal: Guided Sketch-based System • Creating an easy-to-use system. • Providing guidance. • Allowing creative variations 10

  11. Our System 11

  12. System Pipeline Online operations 12

  13. System Pipeline 13

  14. Database Constructions • Database … – Part repository Airplanes Chairs – Image repository 14

  15. Part Repository 15

  16. Part Repository • High-level Information – Hierarchy information – Contact points – Symmetry information Hierarchy Contact points Symmetry 16

  17. Image Repository • Sample 114 views on the unit view sphere • Assign camera up-direction for each view position • Extract line drawing image at each view 𝑣 ∗ 𝑣 17

  18. Search Engine • Search engine is based on encoding the patches of all the images in the repository. • Descriptor: BiCE [Zimmermann et al. 2007] • Min-hash [Chum 2008] BiCE 101011…011010110 ac...ddt Min-Hash code 18

  19. System Pipeline Online Operation 19

  20. Online Operation 20

  21. View-dependent Retrieval 1 3d voting histogram Up-direction Alignment retrieved parts 21

  22. Shadow Composition S * = a å • Shadow image W i I i • Hierarchy-based shadow image 22

  23. Shadow Composition 23

  24. Part Conjoining • Contact point guided conjoining • Symmetry information 24

  25. Creative Modeling • Global fitting – The silhouette of the top candidate is fitted to the drawing strokes. • Local editing – Sketch based local deforming. 25

  26. RESULTS 26

  27. Results Speed: 𝟑𝟏𝟏% 27

  28. Results × 𝟒 28

  29. Results Bicycle models created by users using our system. 29

  30. User Study • Modeling with/without shadow guidance. 30

  31. Limitation • Limited variations of the model. • Part placement. • Inconsistent segmentation. 31

  32. Summary • A sketch-based modeling system – provides shadow suggestions to guide the user’s drawing dynamically – preserves the high-level geometry structure – provides geometric variations 3D models created by users using our system 32

  33. Thank you for your attention! Project page: http://staff.ustc.edu.cn/~lgliu/Projects/2013_3DShadowModeling/default.htm 3D models created by users using our system 33

Recommend


More recommend