The mouse operates in 2d screen space. The camera is 3d. Perhaps you want to project the mouse into the world and find a vector to rotate around that position.
Thank you for your reply.Sorry for the unclear description of my problem.
I can get the position of the mouse click, but I want to set it as the center of rotation.Is there any easy way.Just like a spring arm, the center of rotation of the camera is one end of the spring arm.I need to dynamically modify the rotation center, according to the mouse click position