[DVIPDFMx] Overprinting with xelatex

[Matthias Franz]

Hello,

I'm not familiar with overprinting, but it might help to explain
how to translate from pdftex code to dvipdfmx.  (I didn't test
the functionality, but the code below compiles fine.)

pdftex:
>     \immediate\pdfobj{<< /Type /ExtGState /op false /OP false /OPM 0 >>}
>     \edef\op at off{\the\pdflastobj}
>     \immediate\pdfobj{<< /Type /ExtGState /op true /OP true /OPM 1 >>}
>     \edef\op at on{\the\pdflastobj}
>     \immediate\pdfobj{ << %
>       /GSko \op at off\space 0 R %
>       /GSop \op at on\space 0 R >>}
>     \edef\@extgs{\the\pdflastobj}
>     \edef\next{\global\noexpand\pdfpageresources={\the\pdfpageresources
>       \space /ExtGState \@extgs\space 0 R }}

dvipdfmx:
\special{pdf:obj @opoff << /Type /ExtGState /op false /OP false /OPM 0 >>}
\special{pdf:obj @opon  << /Type /ExtGState /op true /OP true /OPM 1 >>}
\special{pdf:obj @extgs << /GSko @opoff /GSop @opon >>}
\special{pdf:put @resources << /ExtGState @extgs >>}

(See the dvipdfm manual for the list of predefined objects like @resources.)

pdftex:
>       \pdfliteral direct {/GSop gs}%

dvipdfmx:
\special{pdf:literal direct /GSop gs}


Best,
-- 
Matthias