Base input event type for mouse events. Stores general mouse events information. http://docs.godotengine.org/en/3.0/learning/features/inputs/inputevent.html Mouse button mask identifier, one of or a bitwise combination of the BUTTON_MASK_* constants in [@GlobalScope]. Mouse position relative to the current [Viewport] when used in [method Control._gui_input], otherwise is at 0,0. Mouse local position relative to the [Viewport]. If used in [method Control._gui_input] the position is relative to the current [Control] which is under the mouse.