According to what I've been able to discover, the XPS Document Viewer is a
WPF application (Windows Presentation Foundation see
http://msdn2.microsoft.com/en-us/library/ms754130.aspx) and thus uses the
MXDC (Microsoft XPS Document Converter) using bypass for sending output to
the XPS Document Writer - there will not be GDI conversion.
I'm curious, why would you open an XPS Document in the XPS Document Viewer,
then "print" using the XPS Document Writer? You're going to get another XPS
Document, which "should be" functionally equivalent to the original, if not
identical.
Not sure what you mean by the "Global Graphics XPS Driver", but the XPS
Document Viewer will use the WPF Printing API to send output to a driver
that is an XPS driver - there won't be intermediate GDI conversion.
I visited the Global Graphics web site (e.g.
http://www.globalgraphics.com/xps/implementation.html), but could find
specifically a "Global Graphics XPS Driver". Based on the information at
this page, if Global Graphics says their "driver" is an XPS driver, then
presumably there will not be GDI conversion IF the application using it is a
WPF application. Note however, that if the target printer is not an "XPS
printer", the driver will have to convert the XPS document to the language
the printer knows about (e.g. HP PCL or Postscript, IBM's AFP) - this
appears to be at least one of Global Graphics specialties.
If you use an application that uses GDI (i.e. an application that has not
been built or modified to use WPF) to send output to any XPS driver, there
will be GDI to XPS conversion. Most existing applications use GDI. WPF
(Windows Presentation Foundation see
http://msdn2.microsoft.com/en-us/library/ms754130.aspx) is a new set of APIs
(introduced with .Net Framework Version 3) that applications can use for
display as well as printing, but they have to written (or modified) to use
that API set instead of the GDI API set.
