It would be great if there was some tool to measure distances (in points, mm, cm, dpi) and perhaps areas in an PDF. I'd imagine zooming in as much as necessary, then choosing the measurement tool, and dragging a line (resp. a rectangle) on the screen; either the status bar or a hovering popup could show the distance in some choosable units (one or multiple). Thanks a lot!
additional to just being able to measure sheet distance allowing for a scaling option on the reported distance would make Okular incredibly useful for the Architecture, Engineering, and Construction (AEC) market. We typically need to scale dimensions from drawings and right now the opensource options for this are extremely limited to work arounds with either InkScape or GIMP.
Hi! I totally support this initiative. There is really a lack for this type of functionality in Linux. Unfortunately, I don't have the coding skills to do this myself, but I have used software with this functionality at my job and I can give some feedback on how the user experience usually is (to hopefully help to someone actually make it true :) ). Usually there are 2 types of ways for performing measurements into a document: ## Option 1 ("Easy") - The user selects the "calibration button" - The user picks two points in the document - A popup window appears asking the user for introducing the distance of those 2 points (in a drop-down menu you can select the unit) - Okular extracts the distance between 2 points and "calibrates" the document accordingly (using the dimensions of the page of the document) - The user now can select the "measure" button where two new points can be selected and obtain the desired the distance. ## Option 2 (Probably more tricky) - In the "calibrate" option there are a set of default scales the user can pick from (1:50, 1:100, etc. specifying the units, of course) - Knowing the dimensions of page, the calibration is set up and the user can measure as above. Once is developed the functionality can be extended in the future using with extra calculations such as simple areas (squares, circles), the perimeter of a polyline/polygone, etc. I'm aware that this is easier said than done, but I think quite some people could benefit from this!
Additionally, PDF documents can have Measurament data for the real-world scale transformation. Check section 12.9 of the PDF standard: https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008.pdf