| shift | The state of the shift keys and mouse buttons that were pressed at the same time when the mouse was moving.
It is a combination of the following values by bit OR. ssAlt : ALT key was pressed ssShift : SHIFT key was pressed ssCtrl : CTRL key was pressed ssLeft : Left mouse button was pressed ssMiddle : The middle mouse button was pressed ssRight : The right mouse button was pressed |
| delta | The rotation angle of the wheel. Positive when turned up (opposite to the user), negative when turned down (toward the user). Usually the minimum amount is 120. |
| x | The value of the x coordinate (in client coordinates) of the position where the wheel has rotated. |
| y | The value of the y coordinate (in client coordinates) of the position where the wheel has rotated. |