ladybird/Userland/Libraries/LibWeb/UIEvents/MouseEvent.idl

// https://w3c.github.io/uievents/#mouseevent
[Exposed=Window, UseNewAKString]
interface MouseEvent : UIEvent {

    readonly attribute double offsetX;
    readonly attribute double offsetY;
    readonly attribute double clientX;
    readonly attribute double clientY;
    readonly attribute double screenX;
    readonly attribute double screenY;
    readonly attribute double x;
    readonly attribute double y;
    readonly attribute double pageX;
    readonly attribute double pageY;

    // https://w3c.github.io/pointerlock/#extensions-to-the-mouseevent-interface
    readonly attribute double movementX;
    readonly attribute double movementY;

    readonly attribute short button;
    readonly attribute unsigned short buttons;
};

dictionary MouseEventInit : EventModifierInit {

    // FIXME: offsetX and offsetY shouldn't be here.
    double offsetX = 0;
    double offsetY = 0;
    double clientX = 0;
    double clientY = 0;

    // https://w3c.github.io/pointerlock/#extensions-to-the-mouseeventinit-dictionary
    double movementX = 0;
    double movementY = 0;

    short button = 0;

};