Set Top and Left Offset

This type of target point at specific coordinates in the page, the zoom factor is inherited from the current setting of the reader. This is useful when you have very large pdf pages (like maps) and you want to make bookmarks pointing to specific locations in the page. I have also seen that a lot of tools use this type of target when generating bookmarks for pdf files, I think this is to let the user choose a zoom factor that permits him to read the page comfortably and still have their bookmarks working properly, this is a valuable behavior. In jpdfbookmarks offsets can be specified in thousandths of the page extension in a particular direction, so if you want to point to the middle of the page you have to specify a top offset of 500. To be more precise i recommend the use of rulers, for instructions on how to use it read the relative section.