Re: [Indic-computing-devel] Re: NCST Indix Examined

[<jk...@Fr...>]

ks> While starting my work on IndiX, I also decided to give support
ks> using an X extension. But unfortunately, I had to work under
ks> strictly imposed constraints :-( esp. that applications should not
ks> be modified for Indian language support. So I did the thing in
ks> whatever way the people wanted me to do and also tried to do it in
ks> best possible way!

Most unmodified X applications may not work correctly with an X server
that does "behind-the-scenes" glyph reordering and substitution.

Consider the following scenario:
  - the user presses Button-1 down on some `x[1],y[1]' location on screen
    and sweeps the pointer over the screen
  - Button-1 is released at location `x[2],y[2]'

These screen coordinates get reported back to the application in the
form of "events".  Given these two pixel coordinates, the X
application has to figure out the region of the underlying text that
was "selected".  This involves going backwards from 'x,y' coordinates
to the character code points in its text buffer.

If the X server is doing arbitrary glyph reordering and glyph
substitution unknown to the X client, then this translation will go
wrong in the client.

I don't think the requirement of X applications running unchanged with
Indic scripts is a feasible one.

Regards,
Koshy
<jk...@fr...>