On Thu, 2008-06-12 at 15:55 +1000, Hedley Finger wrote:
You have touched on a very important but very confusing subject.
Trouble is this doesn't translate to PDF via the Cairo processor, or to PS and PDF via Ghostscript. The clipping of the bitmap is lost and the the border path just appears as an object on top of the full rectangular bitmap. The text labels are aliased in a very ugly way when I try to output to PNG.
Clipping is not supported in PS and PDF output via the "Save As" dialog. For some reason, it appears that Inkscape has two different PDF Cairo routines (pdf-cairo.cpp and cairo-render-context.cpp) -> WHY??? <-. The code (v0.46) used by the "Print" dialog (cairo-render-context.cpp) does support clipping (but crashes with masks). While the code used by the "Save As" dialog (pdf-cairo.cpp) doesn't support clipping or masks.
Have you tried increasing the resolution for the PNG output?
So I thought to convert the bitmap to a pattern, then fill the horseshoe path with the pattern. No joy. The bitmap turns into a slightly smaller rectangular pattern that is divided into four unequal quadrants, that is, it is tiled.
Patterns are incorrectly exported in the Cairo based PS and PDF output.
https://bugs.launchpad.net/inkscape/+bug/217212
It appears that the "Print" dialog method does export a pattern correctly if it has not been transformed.
It looks nothing like the demonstration on page 190 (204 of 341) of /Inkscape: Guide to a Vector Drawing Program/. This shows a picture of a 1920s couple getting into an early MG sports car, then the same picture used as a fill in a circular object, then the pattern translated to change the details included in the fill.
Just tested, this works fine in Inkscape 0.46 and as a PNG export. The image (left object) and untransformed (middle object) are "printed" correctly to PDF. The transformed (right object) is not.
Tav