Screen Space Curvature and Ambient Occlusion

Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 693)

Abstract

Curvature plays an important role in computer graphics. It helps us to better understand surfaces of various objects. We often deal with a discrete geometry. However, the exact curvature can only be evaluated for analytical surfaces and not for discrete ones. Existing algorithms estimate curvature for discrete geometry with a certain precision. Most of the time, the performance of those algorithms is low and they are not intended to be used in real time applications. Our target is to have a real time curvature estimation that can be used during interactive geometry changes, like in a virtual sculpting. This paper proposes a screen space technique which estimates two principal curvatures and their directions at interactive rates. Final curvature can be used for an ambient occlusion estimation. The proposed solution is created to fit directly into existing rendering pipelines.

Keywords

Curvature Screen space GPU Ambient occlusion Visualisation Discrete differential geometry Computer graphics 

Notes

Acknowledgement

This work was supported by the Czech Ministry of Education, Youth and Sports – the project LO1506 and University spec. research – 1311; and by the UWB grant SGS-2016-013 Advanced Graphical and Computing Systems.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Martin Prantl
    • 1
  • Libor Váša
    • 1
    • 2
  • Ivana Kolingerová
    • 1
    • 2
  1. 1.Department of Computer Science and Engineering, Faculty of Applied SciencesUniversity of West BohemiaPlzenCzech Republic
  2. 2.New Technologies for the Information Society (NTIS)University of West BohemiaPlzenCzech Republic

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