How to get mouse click (x, y) position?

Must I use JavaScript on the clicked element, el:

el.addEventListener(“click”, getClickPosition, false);

Plus the JavaScript function

function getClickPosition(e) {
xPos = e.clientX;
yPos = e.clientY;
Where x & yPos are Global vars so they remain after the click?

If so, then do I have direct access to the JavaScript Global vars, x & yPos or do I need add another JavaScript function to call from Oxygene to get the vars for me? [I know how to get the click in Oxygene via WebAssemblyDelegate].