How to superimpose two pictures?

Hello, I am looking PaintImage method of TASImage class because I would like to superimpose two pictures: I have a TH1F and I would like to superimpose in an area of this TH1F an TImage before exporting it to keep a good resolution (if I add my picture after the export, my picture is ugly). So if I understood correctly PaintImage may do what I want. But I do not understand what is the first parameter. The documentation says

but I do not know what is wid and what is the type Drawable_t. Could you give a example, please? I did not find anythind is the user guide 5.26

see the examples here:
root.cern.ch/root/html/tutorials … index.html

Indeed, I found what I want here. Thank you.