The addfile plugin places a page, selected from another file, into the document at a specified position. You may select the file directly, or dynamically (i.e the file selected is determined by the value of a data-field).
The top-left corner of the chosen file-page is placed relative to a reference point. The corners of the document define four of the reference points; to offset the image relative to a corner, specify a horizontal and a vertical distance towards the middle of the document. The position of the field that called addfile provides more reference points. Offset distances from the field reference points are measured downwards to the right, i.e. towards the bottom-right of the page.