Arbitrary rotation around a point works except when up flips?

Questions & Answers
1

I’ve been working on the ability to rotate my camera around an arbitrary point based on mouse movement and have it working great except when it crosses the top/bottom of an axis. The code for moving the camera is:

					// Get mouse inputs
					float horizontalSpeed = 1.0f;
					float verticalSpeed = 1.0f;
			        float h = horizontalSpeed * Input.GetAxis("Mouse X");
			        float v = verticalSpeed * Input.GetAxis("Mouse Y");

					Vector3 upDirection = Camera.main.transform.up * h;
					Vector3 rightDirection = Camera.main.transform.right * v;
					Vector3 totalDirection = upDirection + rightDirection;
				

					// Set camera variables
					Camera.main.transform.position = MathHelp.Vector3Help.RotateAroundAPoint(Camera.main.transform.position, 

						Vector3.zero, 
					Quaternion.Euler(totalDirection));
					Camera.main.transform.LookAt(Vector3.zero);

Note I have to multiply the up direction by the horizontal axis, and vice versa. And the code for rotating around a point is:

		public static Vector3 RotateAroundAPoint(Vector3 point, Vector3 pivot, Quaternion angle)
		{
			// Center the point around the origin
			Vector3 finalPos = point - pivot;
			
			// Rotate the point
			finalPos = angle * finalPos;
			
			// Move back in place
			finalPos += pivot;
			return finalPos;
		}

Any thoughts?

My goal is to try and be able to rotate the camera in a sphere anywhere.

2

Here, delta is a Vector2 containing the mouse movement (like h and v above); center is the point you’re rotating around; RotationSpeed is a speed multiplier. You might want to switch magnitude for sqrMagnitude.

void SphericalPan(Vector2 delta, Vector3 center, float RotationSpeed)
{
    float Angle = delta.sqrMagnitude;
    if(Angle > 0.0f)
    {
        Vector3 Axis = Vector3.Cross(delta, Vector3.forward);
        Axis=Camera.main.transform.TransformDirection(-Axis);
        Camera.main.transform.RotateAround(center, Axis, Angle * RotationSpeed);
    }        
}