I am working with documents that are PDF files of CAD drawings. The drawings have a border around them, but the border is not always the same distance from the edge of the page. I need to know what this distance from the edge of the page to the border is. I guess that's called the margin.
Is there a way I can set a point in the document and tell whether there is something printed at that point? I'm thinking I can start at the edge of the page and move over, testing each point, until I find one that has some printing. When I get that, I'll have the edge of the border.
Make sense? How do I test a point?