Building up a VR interactive scene

Considered that VR technology is not mature yet for the time being, desktop-based VR can generate a much more vivid world compared with portable device despite its poor portability. VR application has already possessed great variety and applied in gaming, medical, tourism even building construction thanks to its immersive, interactive and imaginative. However, design of interaction as well as choose of VR device and development tool for VR application are different from each other currently, making it difficult to realize real-time monitoring on VR application performance. Desktop-based VR based on Unity 3D engine and HTC Vive device are applied in this paper for VR interactive scene design and real-time monitor via monitoring SDK.
2.1 Introduction on Virtual Reality Toolkit
Virtual Reality Toolkit, or VRTK, provides the scripts of following features:
  1. Event associated with device input and interaction. As an input, HTC Vive provides Touchpad panel, Grip button, Trigger button, Application Menu button and System button, shown as Fig.1. Each event is activated upon user input via pressing the button, where developers can define the content in detail. In addition, man-machine interact including touch, grab and use of object are all linked to an event respectively which is independent from events triggered from input. Such independence can provide developer with more flexibility in development via combining different button events and interaction events.
  2. World pointer. World pointer is a visible laser beam launched from joystick designed for aiming at the target in VR application scenes. It is usually used as a method of selecting the target position in user displacement, or confirming the object for interaction in design of VR interactions.
  3. User displacement. In VR scenes, user realize displacement either in speed mode or destination mode, where scripts are applied respectively for developers to execute, and extend if necessary.
  4. Interact with object via joystick. Interaction can be realized once the scripts allowing for interact are associated with object in VR scene and joystick simultaneously. VRTK provides developers with simple interaction including touch, grab and use an object via joystick.