Hi, I'd like to develop a PDF Reader for iOS that is capable of viewing 3D PDFs (PDFs which have a 3D model embedded in them, usually in .IFC, .U3D, or .PRC format). My thinking is that when the pdf is loaded and rendered, there must be some way to recognise the 3d content and instruct the renderer (PDFKit?) how to treat it (which would be to display it as a model within the bounds of the frame it is embedded in, in the document). I'm not sure how to approach this and would appreciate a bit of guidance to direct my research. Cheers.