Fix QFontMetrics::lineWidth() for fonts with defined point size

QFontMetrics::lineWidth() and ::underlinePos() return value 1
regardless of the font size if the size was defined in points
(instead of pixels).

(On Symbian) QFontMetrics::lineWidth() calls
QFontEngine::lineThickness() which uses its fontDef.pixelSize in
order to come up with a suitable line width. If the QFont size
was defined in points, Qt needs to make sure that fontDef.pixelSize
is set accordingly. This patch adds the code to make sure that
QFontEngine::fontDef always has a valid pixel size.

tst_QFontMetrics::lineWidth() was added, wich failed before and
passes after this patch.

Task-Number: QTBUG-13009
Autotest: Passes
Reviewed-By: Eskil

2 files changed, 25 insertions, 1 deletions

diff --git a/src/gui/text/qfontdatabase_s60.cpp b/src/gui/text/qfontdatabase_s60.cpp
index ec252cd..5e168c6 100644
--- a/src/gui/text/qfontdatabase_s60.cpp
+++ b/src/gui/text/qfontdatabase_s60.cpp
@@ -453,7 +453,7 @@ QFontDef cleanedFontDef(const QFontDef &req)
     return result;
 }
 
-QFontEngine *QFontDatabase::findFont(int script, const QFontPrivate *, const QFontDef &req)
+QFontEngine *QFontDatabase::findFont(int script, const QFontPrivate *d, const QFontDef &req)
 {
     const QFontCache::Key key(cleanedFontDef(req), script);
 
@@ -498,8 +498,14 @@ QFontEngine *QFontDatabase::findFont(int script, const QFontPrivate *, const QFo
                 static_cast<const QSymbianFontDatabaseExtrasImplementation*>(db->symbianExtras);
         const QSymbianTypeFaceExtras *typeFaceExtras =
                 dbExtras->extras(fontFamily, request.weight > QFont::Normal, request.style != QFont::StyleNormal);
+
+        // We need a valid pixelSize, e.g. for lineThickness()
+        if (request.pixelSize < 0)
+            request.pixelSize = request.pointSize * d->dpi / 72;
+
         fe = new QFontEngineS60(request, typeFaceExtras);
 #else // QT_NO_FREETYPE
+        Q_UNUSED(d)
         QFontEngine::FaceId faceId;
         const QtFontFamily * const reqQtFontFamily = db->family(fontFamily);
         faceId.filename = reqQtFontFamily->fontFilename;
diff --git a/tests/auto/qfontmetrics/tst_qfontmetrics.cpp b/tests/auto/qfontmetrics/tst_qfontmetrics.cpp
index a22d624..41121a5 100644
--- a/tests/auto/qfontmetrics/tst_qfontmetrics.cpp
+++ b/tests/auto/qfontmetrics/tst_qfontmetrics.cpp
@@ -74,6 +74,7 @@ private slots:
     void bypassShaping();
     void elidedMultiLength();
     void elidedMultiLengthF();
+    void lineWidth();
 };
 
 tst_QFontMetrics::tst_QFontMetrics()
@@ -266,5 +267,22 @@ void tst_QFontMetrics::elidedMultiLengthF()
     elidedMultiLength_helper<QFontMetricsF>();
 }
 
+void tst_QFontMetrics::lineWidth()
+{
+    // QTBUG-13009, QTBUG-13011
+    QFont smallFont;
+    smallFont.setPointSize(8);
+    smallFont.setWeight(QFont::Light);
+    const QFontMetrics smallFontMetrics(smallFont);
+
+    QFont bigFont;
+    bigFont.setPointSize(40);
+    bigFont.setWeight(QFont::Black);
+    const QFontMetrics bigFontMetrics(bigFont);
+
+    QVERIFY(smallFontMetrics.lineWidth() >= 1);
+    QVERIFY(smallFontMetrics.lineWidth() < bigFontMetrics.lineWidth());
+}
+
 QTEST_MAIN(tst_QFontMetrics)
 #include "tst_qfontmetrics.moc"