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

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

as> Another observation: X doesn't seem to be consistent on where the
as> character -> glyph mapping should be done. While many sources hint
as> that the codes in the requests (for eg: PolyText, RENDER extension
as> etc) should be glyph codes, there are others who indicate that the
as> values stored in XSelections should be UTF-8. 

X selections are a client side concept: defined and managed by
clients, not the X server.  Selections are built using X "properties"
(name/value pairs).

The X server serves as a repository for properties but does not deal
with their contents.

This is basic X (application) programming stuff.  

as> However, if your point was that the client can't easily map (x[1],
as> y[1], x[2], y[2]) to a UTF-8 string, I don't think it would be
as> much harder than the existing algorithms in:
as> xc/lib/Xaw/AsciiSink.c - FindPosition() 
as> In a nutshell, the server, which has the knowledge of complex
as> glyph codes and reordering, responds to client requests for
as> XQueryTextExtents.

Well, the Xaw widget set doesn't seem to be using XQueryTextExtents()
at all.

I'd really like to see this 'not so hard' algorithm whose existence
you have postulated :).

as> I think we should bring this up on the right XFree86 fora and
as> resolve it there.

I think that it would be prudent to first understand how the X window
system actually works.  Especially so, if you are going to claim that
the X protocol specification is ambiguous/in error, and that the error
has been undetected for the two decades (or so) that the specification
has been around :).

Here is a short list of reading material, that I found useful:

o Among others, O'Reilly Inc. publishes a set of books on X window
  system programming which cover the basics of the system.  People who
  are interested on working with/extending X SHOULD first read and
  understand these.

o The mailing lists hosted at XFree86.org are a good resource, though
  they assume that you are already familiar with the basic design
  issues.

o The newsgroup "comp.windows.x" is another resource which could be
  useful on the days the S/N ratio is tolerable.

o Documentation in the X source tree "xc/doc/*"


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