The svg is inserted into PDF by using PDF commands to draw and fill
lines and curves. This means that the graphical objects created with
this remain as vector graphics.
There are a number of SVG things that cannot be converted directly into
PDF. Parts of the graphic such as effects, patterns and images are inserted
into the PDF as a raster graphic. The resolution of this graphic may not
be ideal depending on the FOP dpi (72dpi) and the scaling for that graphic.
This needs to be improved.
Another important note is that text is converted and drawn as a
set of shapes by batik. This means that a typical character will
have about 10 curves (each curve consists of at least 20 characters).
This can make the pdf files large and when the pdf is viewed the
viewer does not normally draw those fine curves very well (turning on
Smooth Line Art in the Acrobat preferences will fix this).
If the text is inserted into the PDF using the inbuilt text commands
for PDF it will use a single character.
It is possible to make sure that all text is drawn into PDF using the
PDF text commands by adding the following to the user config:
The drawback from this is that all text will be confined to text that is
possible for PDF fonts (including embedded fonts) and implemented with
this workaround. The fonts available are the standard pdf fonts and any
fonts that you have embedded using FOP. The font sizes will be rounded
to an integer value. In future this will be improved.
Currently transparency is not supported in PDF so many svg images that
contain effects or graphics with transparent areas will not be displayed