  Reconstructing 3D models from large, dense point clouds is critical to enable
Virtual Reality (VR) as a platform for entertainment, education, and heritage
preservation. Existing 3D reconstruction systems inevitably make trade-offs
between three conflicting goals: the efficiency of reconstruction (e.g., time
and memory requirements), the visual quality of the constructed scene, and the
rendering speed on the VR device. This paper proposes a reconstruction system
that simultaneously meets all three goals. The key idea is to avoid the
resource-demanding process of reconstructing a high-polygon mesh altogether.
Instead, we propose to directly transfer details from the original point cloud
to a low polygon mesh, which significantly reduces the reconstruction time and
cost, preserves the scene details, and enables real-time rendering on mobile VR
devices.
  While our technique is general, we demonstrate it in reconstructing cultural
heritage sites. We for the first time digitally reconstruct the Elmina Castle,
a UNESCO world heritage site at Ghana, from billions of laser-scanned points.
The reconstruction process executes on low-end desktop systems without
requiring high processing power, making it accessible to the broad community.
The reconstructed scenes render on Oculus Go in 60 FPS, providing a real-time
VR experience with high visual quality. Our project is part of the Digital
Elmina effort (http://digitalelmina.org/) between University of Rochester and
University of Ghana.
