Tiny Item Animations The cursor animation

The stack held on the cursor gets its own version of the effect. Picking a stack up starts its animation from zero, and the icon grows smoothly as it is carried, reaching full size and staying there while it follows the pointer.

The practical effect is that the item being carried is bigger than everything underneath it, which keeps it readable while it passes over a dense grid of other items. Like the slot animation, it scales around the item's own centre, so the enlarged icon stays exactly under the pointer rather than sliding off to one side.

Putting the stack down resets its progress, so the next pickup animates again from the beginning.