Diploma and Master Theses (authored and supervised):
"VRNet - A framework for multi-user Virtual Reality";
Supervisor: H. Kaufmann, I. Podkosova;
Institut für Visual Computing & Human-Centered Technology,
Multi-user VR applications are challenging to develop and maintain. They are required
to be highly responsive to not cause discomfort to users. Potential network issues, like
delays and loss of connection, need to be taken into account.
The goal of this thesis is to design and implement a framework to provide developers
with the necessary tools to aid networked VR application development. Game engines
like Unreal Engine 4 (UE4) offer tools and a development environment to create complex
multiplayer 3D applications. However, the underlying networking system was not designed
to be used in local walkable VR scenarios. Our approach is to build the VRNet framework
on top of the engine to enhance it with important functionalities. VRNet is implemented
as an UE4 code plugin that extends core classes in C++. As a plugin it can easily be
integrated and used in UE4 projects. It adds capabilities for networked user movement,
interaction and representation in VR. Client-authoritative replication is implemented
to ensure consistency between machines with optimal user experience, guarded from
networking issues. Additionally, interpolation mechanisms are provided to smoothly
simulate other clients.
Furthermore, as a proof of concept, VRNet is integrated into a VR application that is
developed in the scope of a research project by the CeMM Research Center for Molecular
Medicine in cooperation with TU Wien. CeMM Holodeck is an UE4 application for
visualization and interaction with biological data-networks. Another goal of this thesis is
to extend the functionality of the application to allow multiple users to move around in
a shared virtual environment and collaboratively interact with the data-network. The
integration of VRNet was successful and showed that VRNet provides a robust and useful
foundation for the creation of multi-user VR applications.
Evaluation tests were conducted to investigate the performance efficiency of the VRNet
framework, as well as the CeMM Holodeck. The results of the network traffic measurements
show that the used bandwidth is manageable even with high network update rates.
The results also show that resource usage is not noticeably affected by the integration of
VRNet. VRNet offers simplified and efficient development of multi-user VR applications
that are performant and provide smooth user experience.
Multi-user, Virtual Reality, Distribution
Electronic version of the publication:
Created from the Publication Database of the Vienna University of Technology.