A Fast Silhouette Detection Algorithm for Shadow Volumes in Augmented Reality

Real-time shadow generation in virtual environments
and Augmented Reality (AR) was always a hot topic in the last
three decades. Lots of calculation for shadow generation among AR
needs a fast algorithm to overcome this issue and to be capable of
implementing in any real-time rendering. In this paper, a silhouette
detection algorithm is presented to generate shadows for AR systems.
Δ+ algorithm is presented based on extending edges of occluders
to recognize which edges are silhouettes in the case of real-time
rendering. An accurate comparison between the proposed algorithm
and current algorithms in silhouette detection is done to show the
reduction calculation by presented algorithm. The algorithm is tested
in both virtual environments and AR systems. We think that this
algorithm has the potential to be a fundamental algorithm for shadow
generation in all complex environments.

Authors:

• Hoshang Kolivand
• Mahyar Kolivand
• Mohd Shahrizal Sunar
• Mohd Azhar M. Arsad

Keywords:

• Silhouette detection
• shadow volumes
• real-time shadows
• rendering
• augmented reality.

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