Printing in Inkscape is not a pretty picture. There are two main ways to produce PostScript or PDF files. The first is with the “Save As” dialog and the second is with the “Print” dialog. The two ways use different routines! Then within the “Save As” dialog, one can choose two different routines for PostScript output (via Cairo or via an internal routine) and in the “Print” dialog one can chose between Vector and Raster output. The only method that handles Patterns, Clipping, and Masking correctly is printing with rasterized output… but the quality is limited to 72 dpi (despite an entry box for setting dpi). There is support for Patterns, Clipping, and Masking in the Vector code but it doesn’t work correctly. I’ve looked at patterns briefly in the “Print” dialog Vector output. It appears that an extra transformation is being made. Removing this transformation produces correct output for simple test cases. I’ll need to come up with more complicated tests to check it fully. There is also a very confusing code that tries to align patterns to a grid. Why this is necessary with vector output (or even with raster output) is a mystery to me.