In order to provide/calculate value dynamically (each time the tooltip is shown).
In case of the offset, the element related to the tooltip can have been resized and so we have to be able to recalculate the offset each time. It will be the case for zafin, the tooltip is centered vertically compared to the splitter. If the user resizes the windows, the splitter's height will change and the offset to apply to the tooltip will have to be recalculated

Or maybe we want to apply offset only in some case.

I already defined three interfaces for providing dynamically different options, maybe we can generalize these interface in one :
public and interface OptionProvider<T>{
    T get(Element e);
}

This int