PDF support

Sep 5, 2012 at 11:04 AM


I found this document: http://documenttoolkit.codeplex.com/wikipage?title=How%20To%20View%20PDF%20Documents

It says "Important: PDF support is provided by the open source PDF reader that only implements part of the PDF specification. The PDF engine is work in progress and your documents may not render properly."

Which open source PDF reader is used? And what do you mean with "the pdf engine is work in progress"?



Sep 5, 2012 at 12:52 PM

Hi Tim,

The PDF reader is included in the source code of this project. It merely states that the PDF engine is not part of the commercial Document Toolkit library itself. Also, it implements parts of the PDF specification, and therefor correct PDF rendering is not guaranteed.

Kind regards,

- Koen

Nov 27, 2012 at 4:30 PM

Hi Koen,


I tried some PDF and some text are missing and some images are mis-positioned. How big of a project is it for someone not very familiar with PDF spec to complete the PDF rending engine? Any guidance?  I am looking for a PDF viewer with annotation capabilities for Silverlight and this is the closest I can find. Seems the only thing missing is the PDF rendering.



Nov 27, 2012 at 5:03 PM

Hi Jimmy,

Implementing the full PDF spec is a huge operation. The PDF render engine available in this open source project consists of 2 parts, a parser and a renderer. The PDF parser is fairly complete and works fine with most PDF documents. The problem is in the PDF renderer, where PDF objects are translated to XAML. The renderer only implements parts of the PDF specification. Frankly, the PDF spec (1300+ pages, available at http://www.adobe.com/devnet/pdf/pdf_reference.html) is a mess. For example there are many ways to define a font, the Document Toolkit PDF renderer only supports a subset. Same is true for images and color definitions. The PDF renderer does work best with embedded TrueType fonts and JPEG images.

But don't let this stop you from taking the PDF source and tinker with it.

Kind regards,

- Koen