问计算在相机旋转时保持对象居中所需的位置

EN

//Distance between object and camera. Y-axis is pointing up, so we use x and z coordinates.
float R = Vector2.Distance(new Vector2(obj.position.x, obj.position.z),
                            new Vector2(camera.transform.position.x, camera.transform.position.z));
// Lets find rotation from zero to target angle   
float rAngle = Mathf.Deg2Rad * (camera.transform.rotation.eulerAngles.y + angle );
// Using minus cause when we rotate camera to the "right" we have to move it to the"left"
        float x = -R * Mathf.Sin(rAngle);
        float y = -R * Mathf.Cos(rAngle);

// Apply changes.
camera.transform.position = new Vector3(x, camera.transform.position.y, y);
Vector3 cameraRotation = new Vector3(0,  angle,0);
camera.transform.Rotate(cameraRotation);