src/basis/dom/event.js
function mouseY(event){
    if ('pageY' in event)
      return event.pageY;
    else
      return 'clientY' in event
        ? event.clientY +
            (document.compatMode == 'CSS1Compat' ? document.documentElement.scrollTop : document.body.scrollTop)
        : 0;
  }
function mouseY(event){
    if ('pageY' in event)
      return event.pageY;
    else
      return 'clientY' in event
        ? event.clientY +
            (document.compatMode == 'CSS1Compat' ? document.documentElement.scrollTop : document.body.scrollTop)
        : 0;
  }
function mouseY ( event ) { if ( 'pageY' in event ) return event . pageY ; else return 'clientY' in event ? event . clientY + ( document . compatMode == 'CSS1Compat' ? document . documentElement . scrollTop : document . body . scrollTop ) : 0 ; }
Returns mouse click vertical page coordinate.
@param {Event} event
@return {number}
Returns mouse click vertical page coordinate .