I have a weird issue going on right now with my tool tips. Basically I have an item picker window, that fills a scrollview-grid system with the items matching a filter from my inventory, but it only displays the item icon. When I hover my mouse cursor over the icon, I want a tool tip to display the extended details of that item. The code I am using to position the tool tip is here:
Vector3 mousePosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
transform.OverlayPosition(mousePosition, Camera.main, UICamera.mainCamera);
That code is located on a script attached to the tooltip. If I hover my mouse over the center of the item icon the tool tip upper left corner should display at my mouse cursor point. But instead it is doing this:

You can see the tooltip is off in the bottom left corner, even though my mouse position is in the center of the pink square. So what am I doing wrong?