Add support for QRawFont in QTextLayout.

The purpose of this change is to allow shaping complex
text while using QRawFont.
This is needed for WebKit so that we can switch to
using QRawFont everywhere and be more in line with
what other WebKit ports do.
Since this change slightly bends the aim of QRawFont,
let's reserve this for internal use for now.

Change-Id: I5ec0881f50ce288350bd277570cb5f1fb70c355c
Reviewed-by: Simon Hausmann <simon.hausmann@nokia.com>

1 files changed, 35 insertions, 9 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index 943caea644..d5b05a8957 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -361,6 +361,22 @@ QTextLayout::~QTextLayout()
         delete d;
 }
 
+#ifndef QT_NO_RAWFONT
+/*!
+    \internal
+    Sets a raw font, to be used with QTextLayout::glyphRuns.
+    Note that this only supports the needs of WebKit.
+    Use of this function with e.g. QTextLayout::draw will result
+    in undefined behaviour.
+*/
+void QTextLayout::setRawFont(const QRawFont &rawFont)
+{
+    d->rawFont = rawFont;
+    d->useRawFont = true;
+    d->resetFontEngineCache();
+}
+#endif
+
 /*!
     Sets the layout's font to the given \a font. The layout is
     invalidated and must be laid out again.
@@ -370,6 +386,9 @@ QTextLayout::~QTextLayout()
 void QTextLayout::setFont(const QFont &font)
 {
     d->fnt = font;
+#ifndef QT_NO_RAWFONT
+    d->useRawFont = false;
+#endif
     d->resetFontEngineCache();
 }
 
@@ -2204,15 +2223,17 @@ QList<QGlyphRun> QTextLine::glyphRuns(int from, int length) const
             continue;
         }
 
-        QFont font = eng->font(si);
-
+        QFont font;
         QGlyphRun::GlyphRunFlags flags;
-        if (font.overline())
-            flags |= QGlyphRun::Overline;
-        if (font.underline())
-            flags |= QGlyphRun::Underline;
-        if (font.strikeOut())
-            flags |= QGlyphRun::StrikeOut;
+        if (!eng->useRawFont) {
+            font = eng->font(si);
+            if (font.overline())
+                flags |= QGlyphRun::Overline;
+            if (font.underline())
+                flags |= QGlyphRun::Underline;
+            if (font.strikeOut())
+                flags |= QGlyphRun::StrikeOut;
+        }
 
         bool rtl = false;
         if (si.analysis.bidiLevel % 2) {
@@ -2264,7 +2285,8 @@ QList<QGlyphRun> QTextLine::glyphRuns(int from, int length) const
         iterator.getSelectionBounds(&x, &width);
 
         if (glyphLayout.numGlyphs > 0) {
-            QFontEngine *mainFontEngine = font.d->engineForScript(si.analysis.script);
+            QFontEngine *mainFontEngine = eng->fontEngine(si);
+
             if (mainFontEngine->type() == QFontEngine::Multi) {
                 QFontEngineMulti *multiFontEngine = static_cast<QFontEngineMulti *>(mainFontEngine);
                 int end = rtl ? glyphLayout.numGlyphs : 0;
@@ -2331,6 +2353,10 @@ QList<QGlyphRun> QTextLine::glyphRuns(int from, int length) const
 */
 void QTextLine::draw(QPainter *p, const QPointF &pos, const QTextLayout::FormatRange *selection) const
 {
+#ifndef QT_NO_RAWFONT
+    // Not intended to work with rawfont
+    Q_ASSERT(!eng->useRawFont);
+#endif
     const QScriptLine &line = eng->lines[index];
     QPen pen = p->pen();