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Ray-Tracing Objects and Novel Surface Representations in CGA

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Advances in Computer Graphics (CGI 2019)

Abstract

Conformal Geometric Algebra (CGA) provides a unified representation of both geometric primitives and conformal transformations, and as such holds great promise in the field of computer graphics [1,2,3]. In this paper we implement a simple ray tracer in CGA with a Blinn-Phong lighting model and use it to examine ray intersections with surfaces generated from interpolating between objects [7]. An analytical method for finding the normal line to these interpolated surfaces is described. The expression is closely related to the concept of surface principal curvature from differential geometry and provides a novel way of describing the curvature of evolving surfaces.

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References

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Correspondence to Hugo Hadfield .

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Achawal, S., Lasenby, J., Hadfield, H., Lasenby, A. (2019). Ray-Tracing Objects and Novel Surface Representations in CGA. In: Gavrilova, M., Chang, J., Thalmann, N., Hitzer, E., Ishikawa, H. (eds) Advances in Computer Graphics. CGI 2019. Lecture Notes in Computer Science(), vol 11542. Springer, Cham. https://doi.org/10.1007/978-3-030-22514-8_58

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  • DOI: https://doi.org/10.1007/978-3-030-22514-8_58

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-22513-1

  • Online ISBN: 978-3-030-22514-8

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