Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Xmlgraphics-fop Wiki" 
for change notification.

The following page has been changed by JeremiasMaerki:
http://wiki.apache.org/xmlgraphics-fop/AFPOutput

The comment on the change is:
Some notes and thoughts about AFP fonts for later

------------------------------------------------------------------------------
   * accuracy problems when using bitmap fonts because you can't scale the font 
by fractional point sizes.
   * ...and probably more
  
+ == Fonts ==
+ 
+ At the moment, only AFP bitmap and outline fonts (single-byte) are supported. 
That limits the set of printable characters to what the specified codepage file 
provides. Many fonts, however, have more than 256 glyphs. There are two 
different directions we could take for better Unicode coverage:
+ 
+  1. Add support for double-byte fonts. This is similar to what we do with 
single-byte fonts in PDF and PostScript where multiple single-byte encodings 
are generated. AFP provides double-byte fonts by allowing to span out a matrix 
of codepages. Basically, you select the codepage with the first byte and the 
glyph with the second.
+  1. Add support for TrueType fonts. That's available in newer environments 
and would allow to embed Unicode characters as glyph selectors.
+ 
+ One difficulty will be mapping Unicode scalar values to GCGIDs (Graphic 
Character Global Identifier from IBM's CDRA). GCGIDs are character names with a 
length of 4 to 8 characters. A large collection of Unicode characters can be 
mapped to GCGIDs but there's no 1:1 relationship. However, for most use cases, 
using this subset would probably be sufficient. So far, no machine-readable map 
for Unicode to GCGID could be found. A human-readable map can be found here: 
http://www-01.ibm.com/software/globalization/gcgid/gcgid.jsp. If you have an 
AFP fonts with GCUIDs (Graphic Character UCS Identifier) instead of GCGIDs, 
that might also work because GCUIDs just especially prefixed Unicode values 
expressed as 8 byte string. At the moment, the mapping from Unicode to code 
points (8bit inside the codepage) happens through the "encoding" setting on the 
font configuration element. However, that codepage file/object might also be 
generated by FOP.
+ 
  == Random Notes ==
  
   * We should include resource (especially fonts) at the beginning of the 
print file. That makes sure the resources are available to the viewers and 
reduces the complex setup of fonts. Furthermore, it guarantees that the printer 
always has the most current font files.

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to