Efficient Rendering of Rounded Corners and Edges for Convex Objects

  • Simon CourtinEmail author
  • Sébastien Horna
  • Mickaël Ribadière
  • Pierre Poulin
  • Daniel Meneveaux
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11542)


Many manufactured objects and worn surfaces exhibit rounded corners and edges. These fine details are a source of sharp highlights and shading effects, important to our perception between joining surfaces. However, their representation is often neglected because they introduce complex geometric meshing in very small areas. This paper presents a new method for managing thin rounded corners and edges without explicitly modifying the underlying geometry, so as to produce their visual effects in sample-based rendering algorithms (e.g., ray tracing and path tracing). Our method relies on positioning virtual spheres and cylinders, associated with a detection and acceleration structure that makes the process more robust and more efficient than existing bevel shaders. Moreover, using our implicit surfaces rather than polygonal meshes allows our method to generate extreme close views of the surfaces with a much better visual quality for little additional memory. We illustrate the achieved effects and analyze comparisons generated with existing industrial software shaders.


Rounded edges Bevel Chamfer Shading Implicit surface representation 


  1. 1.
    Autodesk: 3DS Max chamfer modifier.
  2. 2.
    Blender Foundation: Bevel geometry tool in Blender.
  3. 3.
    Blender Foundation: Blender shader for round edges.
  4. 4.
    Blender Foundation: Subdivision tool in Blender.
  5. 5.
    Blender Foundation: Blender (2018).
  6. 6.
    Blender Foundation: Cycles (2018).
  7. 7.
    Catmull, E., Clark, J.: Recursively generated B-spline surfaces on arbitrary topological meshes. Comput.-Aided Des. 10(6), 350–355 (1978)CrossRefGoogle Scholar
  8. 8.
    Chaos group: Corona round-edges shader.
  9. 9.
    Chaos group: V-RAY round-edges shader.
  10. 10.
    Chiyokura, H.: An extended rounding operation for modeling solids with free-form surfaces. In: Kunii, T.L. (ed.) Computer Graphics 1987, pp. 249–268. Springer, Tokyo (1987). Scholar
  11. 11.
    Kajiya, J.T.: The rendering equation. In: ACM SIGGRAPH Computer Graphics, vol. 20, pp. 143–150. ACM (1986)Google Scholar
  12. 12.
    Loubet, G., Neyret, F.: Hybrid mesh-volume LoDs for all-scale pre-filtering of complex 3D assets. In: Computer Graphics Forum, vol. 36, pp. 431–442. Wiley Online Library (2017)Google Scholar
  13. 13.
    Max, N.: Cone-spheres. In: ACM SIGGRAPH Computer Graphics, vol. 24, pp. 59–62. ACM (1990)Google Scholar
  14. 14.
    Pharr, M., Jakob, W., Humphreys, G.: Physically Based Rendering: From Theory to Implementation. Morgan Kaufmann, Burlington (2016)Google Scholar
  15. 15.
    Saito, T., Shinya, M., Takahashi, T.: Highlighting rounded edges. In: Earnshaw, R.A., Wyvill, B. (eds.) New Advances in Computer Graphics, pp. 613–629. Springer, Tokyo (1989). Scholar
  16. 16.
    Stam, J., Loop, C.: Quad/triangle subdivision. In: Computer Graphics Forum, vol. 22, pp. 79–85. Wiley Online Library (2003)Google Scholar
  17. 17.
    Szilvasi-Nagy, M.: Flexible rounding operation for polyhedra. Comput.-Aided Des. 23(9), 629–633 (1991)CrossRefGoogle Scholar
  18. 18.
    Tanaka, T., Takahashi, T.: Precise rendering method for exact anti-aliasing and highlighting. Vis. Comput. 8(5), 315–326 (1992)CrossRefGoogle Scholar
  19. 19.
    Wei, L.Y., Shi, K.L., Yong, J.H.: Rendering chamfering structures of sharp edges. Vis. Comput. 31(11), 1511–1519 (2015)CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Simon Courtin
    • 1
    Email author
  • Sébastien Horna
    • 1
  • Mickaël Ribadière
    • 1
  • Pierre Poulin
    • 2
  • Daniel Meneveaux
    • 1
  1. 1.Univ. Poitiers, CNRS, XLIM, UMR 7252PoitiersFrance
  2. 2.LIGUM, Dept. I.R.O., Université de MontréalMontréalCanada

Personalised recommendations