In this paper, we have proposed a heuristic approach to use gesture based on NUI technology. According to the hand shape we have defined five gestures. This method employs a flexible use of gestures to guarantee the most freedom for users. Even those who have never before used a computer can be accommodated by using gestures from life experience. We used 3D path modification as an application for our research target. We can use hand gesture to create path planning and edit it. Our core method relies on detecting 3D collision points. By detecting collision points, we can test whether a certain event could occur or not, and then we know the condition about the real time path. 3D collision point detection is based on intersection detection, and intersection in nature is a type of interaction. We did a simulation experiment about city path modification. Experiment resulted that computer can accurately identify a valid gesture. By using gesture it can effectively change the path. Among other applications, this solution can be used in virtual military maps and car navigation