Fix RTL layout for fonts when non-printable character has an advance

If a non-printable character has an advance, we would lay out the text
as if the character was part of the output, and then ignore the
character later when the text was rendered. To fix cases such as this,
we take the dontPrint attribute into consideration when adjusting the
advances.

Task-number: QTBUG-21347
Reviewed-by: Eskil
Reviewed-by: Lars
(cherry picked from commit 6326227674efa85c1a5320141041110d211efc75)

Change-Id: I4d01b60498f3b5f30b69530c8b49dd720d83ad0b
Reviewed-on: http://codereview.qt-project.org/4410
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com>

2 files changed, 4 insertions, 2 deletions

diff --git a/src/gui/text/qfontengine.cpp b/src/gui/text/qfontengine.cpp
index 9d42d8ab69..a89bb18e94 100644
--- a/src/gui/text/qfontengine.cpp
+++ b/src/gui/text/qfontengine.cpp
@@ -280,6 +280,8 @@ void QFontEngine::getGlyphPositions(const QGlyphLayout &glyphs, const QTransform
         int i = glyphs.numGlyphs;
         int totalKashidas = 0;
         while(i--) {
+            if (glyphs.attributes[i].dontPrint)
+                continue;
             xpos += glyphs.advances_x[i] + QFixed::fromFixed(glyphs.justifications[i].space_18d6);
             ypos += glyphs.advances_y[i];
             totalKashidas += glyphs.justifications[i].nKashidas;
diff --git a/src/gui/text/qtextengine.cpp b/src/gui/text/qtextengine.cpp
index 95a797439a..91c96fce80 100644
--- a/src/gui/text/qtextengine.cpp
+++ b/src/gui/text/qtextengine.cpp
@@ -968,7 +968,7 @@ void QTextEngine::shapeText(int item) const
     }
 
     for (int i = 0; i < si.num_glyphs; ++i)
-        si.width += glyphs.advances_x[i];
+        si.width += glyphs.advances_x[i] * !glyphs.attributes[i].dontPrint;
 }
 
 static inline bool hasCaseChange(const QScriptItem &si)
@@ -2664,7 +2664,7 @@ void QTextEngine::splitItem(int item, int pos) const
         QFixed w = 0;
         const QGlyphLayout g = shapedGlyphs(&oldItem);
         for(int j = 0; j < breakGlyph; ++j)
-            w += g.advances_x[j];
+            w += g.advances_x[j] * !g.attributes[j].dontPrint;
 
         newItem.width = oldItem.width - w;
         oldItem.width = w;