Add text decoration support to QStaticText

The original code path of QStaticText does not include decoration
drawing, this patch generalized the drawTextItemDecoration()
function to draw decoration for drawText(), then use that to draw
decoration for QStaticText. A helper function called
drawDecorationForGlyphs() is made to allow easier extension for
direct glyphs drawing support.

Task-number: QTBUG-12121
Reviewed-by: Eskil
(cherry picked from commit a1641e27d2e2f5e29362e3737be6b9d75714d138)

1 files changed, 106 insertions, 0 deletions

diff --git a/tests/auto/qstatictext/tst_qstatictext.cpp b/tests/auto/qstatictext/tst_qstatictext.cpp
index 1d166f49e5..0ae5320b82 100644
--- a/tests/auto/qstatictext/tst_qstatictext.cpp
+++ b/tests/auto/qstatictext/tst_qstatictext.cpp
@@ -85,6 +85,10 @@ private slots:
     void setPenPlainText();
     void setPenRichText();
     void richTextOverridesPen();
+
+    void drawStruckOutText();
+    void drawOverlinedText();
+    void drawUnderlinedText();
 };
 
 void tst_QStaticText::init()
@@ -620,5 +624,107 @@ void tst_QStaticText::richTextOverridesPen()
     }
 }
 
+void tst_QStaticText::drawStruckOutText()
+{
+    QPixmap imageDrawText(1000, 1000);
+    QPixmap imageDrawStaticText(1000, 1000);
+
+    imageDrawText.fill(Qt::white);
+    imageDrawStaticText.fill(Qt::white);
+
+    QString s = QString::fromLatin1("Foobar");
+
+    QFont font;
+    font.setStrikeOut(true);
+
+    {
+        QPainter p(&imageDrawText);
+        p.setFont(font);
+        p.drawText(QPointF(50, 50), s);
+    }
+
+    {
+        QPainter p(&imageDrawStaticText);
+        QStaticText text = QStaticText(s);
+        p.setFont(font);
+        p.drawStaticText(QPointF(50, 50 - QFontMetricsF(p.font()).ascent()), text);
+    }
+
+#if defined(DEBUG_SAVE_IMAGE)
+    imageDrawText.save("drawStruckOutText_imageDrawText.png");
+    imageDrawStaticText.save("drawStruckOutText_imageDrawStaticText.png");
+#endif
+
+    QCOMPARE(imageDrawText, imageDrawStaticText);
+}
+
+void tst_QStaticText::drawOverlinedText()
+{
+    QPixmap imageDrawText(1000, 1000);
+    QPixmap imageDrawStaticText(1000, 1000);
+
+    imageDrawText.fill(Qt::white);
+    imageDrawStaticText.fill(Qt::white);
+
+    QString s = QString::fromLatin1("Foobar");
+
+    QFont font;
+    font.setOverline(true);
+
+    {
+        QPainter p(&imageDrawText);
+        p.setFont(font);
+        p.drawText(QPointF(50, 50), s);
+    }
+
+    {
+        QPainter p(&imageDrawStaticText);
+        QStaticText text = QStaticText(s);
+        p.setFont(font);
+        p.drawStaticText(QPointF(50, 50 - QFontMetricsF(p.font()).ascent()), text);
+    }
+
+#if defined(DEBUG_SAVE_IMAGE)
+    imageDrawText.save("drawOverlinedText_imageDrawText.png");
+    imageDrawStaticText.save("drawOverlinedText_imageDrawStaticText.png");
+#endif
+
+    QCOMPARE(imageDrawText, imageDrawStaticText);
+}
+
+void tst_QStaticText::drawUnderlinedText()
+{
+    QPixmap imageDrawText(1000, 1000);
+    QPixmap imageDrawStaticText(1000, 1000);
+
+    imageDrawText.fill(Qt::white);
+    imageDrawStaticText.fill(Qt::white);
+
+    QString s = QString::fromLatin1("Foobar");
+
+    QFont font;
+    font.setUnderline(true);
+
+    {
+        QPainter p(&imageDrawText);
+        p.setFont(font);
+        p.drawText(QPointF(50, 50), s);
+    }
+
+    {
+        QPainter p(&imageDrawStaticText);
+        QStaticText text = QStaticText(s);
+        p.setFont(font);
+        p.drawStaticText(QPointF(50, 50 - QFontMetricsF(p.font()).ascent()), text);
+    }
+
+#if defined(DEBUG_SAVE_IMAGE)
+    imageDrawText.save("drawUnderlinedText_imageDrawText.png");
+    imageDrawStaticText.save("drawUnderlinedText_imageDrawStaticText.png");
+#endif
+
+    QCOMPARE(imageDrawText, imageDrawStaticText);
+}
+
 QTEST_MAIN(tst_QStaticText)
 #include "tst_qstatictext.moc"