Let's trace through how the pop-up system works. When the main scene first loads, the
popup_MainMenu Prefab renders in front of the camera. It does this because it is parented to the main camera's transform as a child object. This means that no matter what position and orientation the camera has, the pop up will move relative to this and always be on the screen, effectively in screen coordinates. This is a common trick in game programming used to achieve quasi-2D screen space results with 3D objects.
New button is clicked, the
popupButtonScript iterates over the action array, and based on the enumeration for the action, it dispatches an appropriate command. For now, we set the
loading level1 and let the