tdf#140731: sw transliteration: avoid too many redlines

As a workaround for the performance regression
from commit 2d3c77e9b10f20091ef338e262ba7756eb280ce9
(tdf#109266 sw change tracking: track transliteration),
switch off redlining to avoid ~freezing, if a single
transliteration could result too many (>~500) redlines.

A single transliteration creates n redlines
for n paragraphs of the selected text, except in
the case of transliterating to title case, where it
creates n redlines for n words. It's very easy
to freeze Writer, because Writer's slowing down with
n redlines is described by an O(n²) (quadratic) time
complexity. Eg. in an experiment, title casing
~660 words was 6 sec, but ~3000 words was 85 sec,
regarding to creating 660 vs 3000 redlines.

Note: this is a partial revert of commit
2d3c77e9b10f20091ef338e262ba7756eb280ce9, if the
selection contains more than 500 paragraphs (or in the
case transliterating to title case, ~500 words).

Change-Id: Iad98943cc9e1ed64aa9779e49ee3e941abad02ac
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/111637
Tested-by: Jenkins
Tested-by: László Németh <nemeth@numbertext.org>
Reviewed-by: László Németh <nemeth@numbertext.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/sw/inc/ndtxt.hxx b/sw/inc/ndtxt.hxx
index 5dbbbc721f37..50986f3daca7 100644
--- a/sw/inc/ndtxt.hxx
+++ b/sw/inc/ndtxt.hxx
@@ -746,7 +746,7 @@ public:
     /// change text to Upper/Lower/Hiragana/Katakana/...
     void TransliterateText( utl::TransliterationWrapper& rTrans,
                             sal_Int32 nStart, sal_Int32 nEnd,
-                            SwUndoTransliterate* pUndo );
+                            SwUndoTransliterate* pUndo, bool bUseRedlining = false );
 
     /// count words in given range - returns true if we refreshed out count
     bool CountWords( SwDocStat& rStat, sal_Int32 nStart, sal_Int32 nEnd ) const;