1 files changed, 37 insertions, 9 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index b2f12ef1ce..30f07ba69b 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -850,6 +850,10 @@ QTextLine QTextLayout::createLine()
     int l = d->lines.size();
     if (l && d->lines.at(l-1).length < 0) {
         QTextLine(l-1, d).setNumColumns(INT_MAX);
+        if (d->maxWidth > QFIXED_MAX / 2) {
+            qWarning("QTextLayout: text too long, truncated.");
+            return QTextLine();
+        }
     }
     int from = l > 0 ? d->lines.at(l-1).from + d->lines.at(l-1).length + d->lines.at(l-1).trailingSpaces : 0;
     int strlen = d->layoutData->string.length();
@@ -1169,10 +1173,17 @@ void QTextLayout::draw(QPainter *p, const QPointF &pos, const QVector<FormatRang
                 QRectF fullLineRect(tl.rect());
                 fullLineRect.translate(position);
                 fullLineRect.setRight(QFIXED_MAX);
-                if (!selectionEndInLine)
-                    region.addRect(clipIfValid(QRectF(lineRect.topRight(), fullLineRect.bottomRight()), clip));
-                if (!selectionStartInLine)
-                    region.addRect(clipIfValid(QRectF(fullLineRect.topLeft(), lineRect.bottomLeft()), clip));
+
+                const bool rightToLeft = d->isRightToLeft();
+
+                if (!selectionEndInLine) {
+                    region.addRect(clipIfValid(rightToLeft ? QRectF(fullLineRect.topLeft(), lineRect.bottomLeft())
+                                                           : QRectF(lineRect.topRight(), fullLineRect.bottomRight()), clip));
+                }
+                if (!selectionStartInLine) {
+                    region.addRect(clipIfValid(rightToLeft ? QRectF(lineRect.topRight(), fullLineRect.bottomRight())
+                                                           : QRectF(fullLineRect.topLeft(), lineRect.bottomLeft()), clip));
+                }
             } else if (!selectionEndInLine
                 && isLastLineInBlock
                 &&!(d->option.flags() & QTextOption::ShowLineAndParagraphSeparators)) {
@@ -1325,13 +1336,13 @@ void QTextLayout::drawCursor(QPainter *p, const QPointF &pos, int cursorPosition
     bool rightToLeft = d->isRightToLeft();
     if (itm >= 0) {
         const QScriptItem &si = d->layoutData->items.at(itm);
-        if (si.ascent > 0)
+        if (si.ascent >= 0)
             base = si.ascent;
-        if (si.descent > 0)
+        if (si.descent >= 0)
             descent = si.descent;
         rightToLeft = si.analysis.bidiLevel % 2;
     }
-    qreal y = position.y() + (sl.y + sl.base() - base).toReal();
+    qreal y = position.y() + (sl.y + sl.base() + sl.descent - base - descent).toReal();
     bool toggleAntialiasing = !(p->renderHints() & QPainter::Antialiasing)
                               && (p->transform().type() > QTransform::TxTranslate);
     if (toggleAntialiasing)
@@ -1339,7 +1350,20 @@ void QTextLayout::drawCursor(QPainter *p, const QPointF &pos, int cursorPosition
     QPainter::CompositionMode origCompositionMode = p->compositionMode();
     if (p->paintEngine()->hasFeature(QPaintEngine::RasterOpModes))
         p->setCompositionMode(QPainter::RasterOp_NotDestination);
-    p->fillRect(QRectF(x, y, qreal(width), (base + descent).toReal()), p->pen().brush());
+    const QTransform &deviceTransform = p->deviceTransform();
+    const qreal xScale = deviceTransform.m11();
+    if (deviceTransform.type() != QTransform::TxScale || std::trunc(xScale) == xScale) {
+        p->fillRect(QRectF(x, y, qreal(width), (base + descent).toReal()), p->pen().brush());
+    } else {
+        // Ensure consistently rendered cursor width under fractional scaling
+        const QPen origPen = p->pen();
+        QPen pen(origPen.brush(), qRound(width * xScale), Qt::SolidLine, Qt::FlatCap);
+        pen.setCosmetic(true);
+        const qreal center = x + qreal(width) / 2;
+        p->setPen(pen);
+        p->drawLine(QPointF(center, y), QPointF(center, y + (base + descent).toReal()));
+        p->setPen(origPen);
+    }
     p->setCompositionMode(origCompositionMode);
     if (toggleAntialiasing)
         p->setRenderHint(QPainter::Antialiasing, false);
@@ -1976,7 +2000,8 @@ void QTextLine::layout_helper(int maxGlyphs)
 
                 if (lbh.currentPosition >= eng->layoutData->string.length()
                     || isBreakableSpace
-                    || attributes[lbh.currentPosition].lineBreak) {
+                    || attributes[lbh.currentPosition].lineBreak
+                    || lbh.tmpData.textWidth >= QFIXED_MAX) {
                     sb_or_ws = true;
                     break;
                 } else if (attributes[lbh.currentPosition].graphemeBoundary) {
@@ -2535,6 +2560,9 @@ void QTextLine::draw(QPainter *p, const QPointF &pos, const QTextLayout::FormatR
         return;
     }
 
+    static QRectF maxFixedRect(QPointF(-QFIXED_MAX, -QFIXED_MAX), QPointF(QFIXED_MAX, QFIXED_MAX));
+    if (!maxFixedRect.contains(pos))
+        return;
 
     QTextLineItemIterator iterator(eng, index, pos, selection);
     QFixed lineBase = line.base();