introduce initialCompose for efficiency of ime interaction.

[johnsonj]

Currently it runs for any result(commit) string, which is not efficient (thai language, korean).
it also runs for 0-size composition(preedit) string, which is needless (gtk).

I have tried to make ClearTentativeStart() to be merged into AddCharUTF(), but it is too deep related with undo.
I feel frustrated.

I think it is better to suppress ClearTentativeStart() to run minimal.
ClearTentativeStart() should be performed only once just before first round composition when virtual space on, as the name suggests.

[Neil Hodgson]

johnsonj:

> I think it is better to suppress ClearTentativeStart() to run minimal.
> ClearTentativeStart() should be performed only once just before first round composition when virtual space on, as the name suggests.

If this is purely an optimisation, then it should be deferred. If there is a user-visible effect (extra undo step?) then it may be worthwhile.

Neil

[johnsonj]

Thank you!
It is ok to be defered until reconvert string will be introduced (for gtk and qt).
I wll wait fctix.4.9.2.2 to come or qt for windows to be fixed.