ListeningTestUIPlugin

Overview

This plugin creates an interface between Unreal Engine and a TCP server using CodeSpartan's TcpSocketPlugin in order to collect data from VR listening experiments. This interface allows UI widgets to send data to e.g. Matlab for automatic processing as well as collect head tracking data from HMDs.

User interfaces

In order to display widgets in 3D space, they are attached to actors which are placed in the world. Currently the only widget is a mushra-type interface. This widget allows participants to switch between different levels and rate different attributes using sliders. Data gathered from sliders is automatically send to server.

Messaging

Messages are formatted using a header/body structure, e.g.:

Header: 0 0 0 18 0 0 2    Body: 65 73 72 84 65 80 97 114 107 83 117 109 109 101 114 

With the header containing the length of the message (4 bytes) as well as an op-code detailing the contents of the message (3 bytes) and the body containing the message itself. Numbers are generally converted into strings before being sent, meaning every character is represented by its ASCII value (1 Byte).

Op-Codes:

• 001 Ping (for testing purposes)
• 002 Slider Data, content: SliderNr, LevelState, CurrentLevel, CurrentAttribute, SliderStartValue, Value, SliderDiscrete, ResetOnAttributeChange, TimeSec
• 003 Startup Data, content: SliderAStartValue, SliderBStartValue, SliderCStartValue, ResetSliders, DiscreteSliders, Attributes, HeadTrackingEnabled, LevelNames, RandomizeLevels
• 011 No HMD detected
• 015 Experiment finished, data will be processed

Usage

Drop TcpConnectionActor into your level and set ip address and port number of your server in the actor's detail panel. When connection to a server is successfully established, data will be sent and information is displayed in UE's output log. In order to display UI, drop MushraInterfaceActor into your level.