The MouseMoveEvent class is passed as argument whenever the mouse is moved.
| x, y, dx, dy, x0, y0, dx0, dy0, buttons) |
x/y is the pixel position of the mouse where 0/0 is the upper left corner.
dx/dy is the mouse delta, i.e. the distance travelled since the last event.
x0/y0 is the normalized position of the mouse where each component lies in the range [0,1).
dx0/dy0 is the normalized mouse delta.
buttons contains the mouse buttons that are currently pressed. Each bit corresponds to a mouse button (bit 0 = left button, bit 1 = middle button, etc.).