1 files changed, 13 insertions, 8 deletions

diff --git a/src/gui/painting/qpainter.cpp b/src/gui/painting/qpainter.cpp
index e70079915a..aeb76589e0 100644
--- a/src/gui/painting/qpainter.cpp
+++ b/src/gui/painting/qpainter.cpp
@@ -6183,7 +6183,8 @@ static QPixmap generateWavyPixmap(qreal maxRadius, const QPen &pen)
 
     QString key = QLatin1String("WaveUnderline-")
                   % pen.color().name()
-                  % HexString<qreal>(radiusBase);
+                  % HexString<qreal>(radiusBase)
+                  % HexString<qreal>(pen.widthF());
 
     QPixmap pixmap;
     if (QPixmapCache::find(key, pixmap))
@@ -6191,7 +6192,7 @@ static QPixmap generateWavyPixmap(qreal maxRadius, const QPen &pen)
 
     const qreal halfPeriod = qMax(qreal(2), qreal(radiusBase * 1.61803399)); // the golden ratio
     const int width = qCeil(100 / (2 * halfPeriod)) * (2 * halfPeriod);
-    const int radius = qFloor(radiusBase);
+    const qreal radius = qFloor(radiusBase * 2) / 2.;
 
     QPainterPath path;
 
@@ -6214,7 +6215,7 @@ static QPixmap generateWavyPixmap(qreal maxRadius, const QPen &pen)
         // due to it having a rather thick width for the regular underline.
         const qreal maxPenWidth = .8 * radius;
         if (wavePen.widthF() > maxPenWidth)
-            wavePen.setWidth(maxPenWidth);
+            wavePen.setWidthF(maxPenWidth);
 
         QPainter imgPainter(&pixmap);
         imgPainter.setPen(wavePen);
@@ -6254,9 +6255,6 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
         painter->setRenderHint(QPainter::Qt4CompatiblePainting, false);
 
     const qreal underlineOffset = fe->underlinePosition().toReal();
-    // deliberately ceil the offset to avoid the underline coming too close to
-    // the text above it.
-    const qreal underlinePos = pos.y() + qCeil(underlineOffset) + 0.5;
 
     if (underlineStyle == QTextCharFormat::SpellCheckUnderline) {
         QPlatformTheme *theme = QGuiApplicationPrivate::platformTheme();
@@ -6267,19 +6265,26 @@ static void drawTextItemDecoration(QPainter *painter, const QPointF &pos, const
     if (underlineStyle == QTextCharFormat::WaveUnderline) {
         painter->save();
         painter->translate(0, pos.y() + 1);
+        qreal maxHeight = fe->descent().toReal() - qreal(1);
 
         QColor uc = charFormat.underlineColor();
         if (uc.isValid())
             pen.setColor(uc);
 
         // Adapt wave to underlineOffset or pen width, whatever is larger, to make it work on all platforms
-        const QPixmap wave = generateWavyPixmap(qMax(underlineOffset, pen.widthF()), pen);
-        const int descent = (int) fe->descent().toReal();
+        const QPixmap wave = generateWavyPixmap(qMin(qMax(underlineOffset, pen.widthF()), maxHeight / 2.), pen);
+        const int descent = qFloor(maxHeight);
 
         painter->setBrushOrigin(painter->brushOrigin().x(), 0);
         painter->fillRect(pos.x(), 0, qCeil(width), qMin(wave.height(), descent), wave);
         painter->restore();
     } else if (underlineStyle != QTextCharFormat::NoUnderline) {
+        // Deliberately ceil the offset to avoid the underline coming too close to
+        // the text above it, but limit it to stay within descent.
+        qreal adjustedUnderlineOffset = std::ceil(underlineOffset) + 0.5;
+        if (underlineOffset <= fe->descent().toReal())
+            adjustedUnderlineOffset = qMin(adjustedUnderlineOffset, fe->descent().toReal() - 0.5);
+        const qreal underlinePos = pos.y() + adjustedUnderlineOffset;
         QColor uc = charFormat.underlineColor();
         if (uc.isValid())
             pen.setColor(uc);