From 80294c375eca9687d1c34e9ab048294373e7f00c Mon Sep 17 00:00:00 2001
From: Jiang Jiang <jiang.jiang@nokia.com>
Date: Thu, 8 Sep 2011 16:31:53 +0200
Subject: Fix trailing spaces problem by not adding it to QScriptLine.length

It seems to be the only sane way to fix it. Previous attempts to
fix it by compensating the trailing space width all failed in some
cases, one of the trickiest is when we are having embedded LTR text
that has trailing spaces in a RTL paragraph.

In this patch we leave line.length not including the trailing space
length, but saving it to a separated variable, so that we can always
add it back when needed (QTextLine::textLength() for instance).

It fixed all the problems in different alignments of both RTL and
LTR text. And no regression is found yet.

Reviewed-by: Eskil
---
 src/gui/text/qtextengine.cpp | 2 +-
 src/gui/text/qtextengine_p.h | 3 ++-
 src/gui/text/qtextlayout.cpp | 6 +++---
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/gui/text/qtextengine.cpp b/src/gui/text/qtextengine.cpp
index 6f07131..a0e1751 100644
--- a/src/gui/text/qtextengine.cpp
+++ b/src/gui/text/qtextengine.cpp
@@ -2951,7 +2951,7 @@ int QTextEngine::lineNumberForTextPosition(int pos)
         return lines.size() - 1;
     for (int i = 0; i < lines.size(); ++i) {
         const QScriptLine& line = lines[i];
-        if (line.from + line.length > pos)
+        if (line.from + line.length + line.trailingSpaces > pos)
             return i;
     }
     return -1;
diff --git a/src/gui/text/qtextengine_p.h b/src/gui/text/qtextengine_p.h
index b1bd0c3..0a86886 100644
--- a/src/gui/text/qtextengine_p.h
+++ b/src/gui/text/qtextengine_p.h
@@ -376,7 +376,7 @@ struct Q_AUTOTEST_EXPORT QScriptLine
 {
     // created and filled in QTextLine::layout_helper
     QScriptLine()
-        : from(0), length(0),
+        : from(0), trailingSpaces(0), length(0),
         justified(0), gridfitted(0),
         hasTrailingSpaces(0), leadingIncluded(0) {}
     QFixed descent;
@@ -388,6 +388,7 @@ struct Q_AUTOTEST_EXPORT QScriptLine
     QFixed textWidth;
     QFixed textAdvance;
     int from;
+    unsigned short trailingSpaces;
     signed int length : 28;
     mutable uint justified : 1;
     mutable uint gridfitted : 1;
diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index 4fd6ddf..cf361a0 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -814,7 +814,7 @@ QTextLine QTextLayout::createLine()
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
     }
-    int from = l > 0 ? d->lines.at(l-1).from + d->lines.at(l-1).length : 0;
+    int from = l > 0 ? d->lines.at(l-1).from + d->lines.at(l-1).length + d->lines.at(l-1).trailingSpaces : 0;
     int strlen = d->layoutData->string.length();
     if (l && from >= strlen) {
         if (!d->lines.at(l-1).length || d->layoutData->string.at(strlen - 1) != QChar::LineSeparator)
@@ -1931,7 +1931,7 @@ found:
     if (eng->option.flags() & QTextOption::IncludeTrailingSpaces)
         line.textWidth += lbh.spaceData.textWidth;
     if (lbh.spaceData.length) {
-        line.length += lbh.spaceData.length;
+        line.trailingSpaces = lbh.spaceData.length;
         line.hasTrailingSpaces = true;
     }
 
@@ -1995,7 +1995,7 @@ int QTextLine::textLength() const
         && eng->block.isValid() && i == eng->lines.count()-1) {
         return eng->lines[i].length - 1;
     }
-    return eng->lines[i].length;
+    return eng->lines[i].length + eng->lines[i].trailingSpaces;
 }
 
 static void drawMenuText(QPainter *p, QFixed x, QFixed y, const QScriptItem &si, QTextItemInt &gf, QTextEngine *eng,
-- 
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