The movementY
read-only property of the MouseEvent
interface provides the difference in the Y coordinate of the mouse pointer between the given event and the previous mousemove
event. In other words, the value of the property is computed like this: currentEvent.movementY = currentEvent.screenY - previousEvent.screenY
.
Warning: Browsers use different units for movementY
and screenY
than what the specification defines. Depending on the browser and operating system, the movementY
units may be a physical pixel, a logical pixel, or a CSS pixel.