Funding for this research was provided by:
National Natural Science Foundation of China (41830645, 41625003)
National Key R&D Program of China (2017YFB0503602)
The Open Funding Project of State Key Laboratory of Virtual Reality Technology and Systems (011177220010020)
Article History
Received: 12 June 2018
Revised: 14 November 2018
Accepted: 13 December 2018
First Online: 7 January 2019