People view drones performance at the Orange Isle scenic area in Changsha, central China's Hunan Province, Aug. 16, 2018. Groups of drones performed a light show here to greet the Qixi festival, or Chinese Valentine's Day, which falls on Aug. 17 this year. (Xinhua/Zhang Xiaoyu)

People view drones performance at the Orange Isle scenic area in Changsha, central China's Hunan Province, Aug. 16, 2018. Groups of drones performed a light show here to greet the Qixi festival, or Chinese Valentine's Day, which falls on Aug. 17 this year. (Xinhua/Zhang Xiaoyu)

People view drones performance at the Orange Isle scenic area in Changsha, central China's Hunan Province, Aug. 16, 2018. Groups of drones performed a light show here to greet the Qixi festival, or Chinese Valentine's Day, which falls on Aug. 17 this year. (Xinhua/Zhang Xiaoyu)

People view drones performance at the Orange Isle scenic area in Changsha, central China's Hunan Province, Aug. 16, 2018. Groups of drones performed a light show here to greet the Qixi festival, or Chinese Valentine's Day, which falls on Aug. 17 this year. (Xinhua/Zhang Xiaoyu)