Tracing a pdf

If I wanted to import a building plan PDF and trace over the top to form shapes to get areas, lengths etc in a browser what would the best way to do it?

With a browser? That’s not really possible.

If you use foxit reader, you would be able to draw on it, though I’m not sure about getting any sort of measurements.

You might have to take screenshots of the document, paste the images into a CAD program, and trace it in there to get both shapes are measurements.

I was hoping using a php library to convert PDF to an image and trace with jquery getting screen positions and html5 shapes…

You get a lot more control if you open the PDF in Illustrator. A lot of the content will be editable, or you can draw on top of it in a new layer.