Dears
Before Install, you must have one Chinese Font file installed. use the wqy_zenhei.ttf.
User in Latin is not useful, no effect.
Here is the vertical Layout for Chinese, possible for all CJK, too.
This plugin is modified from original v1.7. Let user can see Vertical text, It uses the benefit of PANGO and FT.
Chinese Vertical layout we must do following things,
for Pango Layer
a) set the base_Gravity to PANGO_GRAVITY_EAST
b) rotate 90
At Font data,
I am not sure whether pango can do following things or not, especialy item (a).
a) unrotated the Latin half glyphs.
b) unrotated the Chinese full vertical scripts.
c) hinting some punctuations.
others are not considered, for example, time, digital index, combinational Hanzi,
bin
Source code
document-viewer-plugins-1.7-vertical CJK plaintext v0.1.zip