Editor: Make line spacing adjustable

Fixes: QTCREATORBUG-13727
Change-Id: I3dbc3277795b339bced81dc6c5a048c828183cb6
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

7 files changed, 197 insertions, 86 deletions

diff --git a/src/plugins/fakevim/fakevimplugin.cpp b/src/plugins/fakevim/fakevimplugin.cpp
index f81b8146cf..cd3509b45e 100644
--- a/src/plugins/fakevim/fakevimplugin.cpp
+++ b/src/plugins/fakevim/fakevimplugin.cpp
@@ -324,7 +324,7 @@ private:
     {
         QTextCursor tc = m_editor->textCursor();
         m_currentPos = tc.position();
-        m_lineSpacing = m_editor->cursorRect(tc).height();
+        m_lineSpacing = m_editor->document()->documentLayout()->blockBoundingRect(tc.block()).height();
         setFont(m_editor->extraArea()->font());
 
         // Follow geometry of normal line numbers if visible,
diff --git a/src/plugins/texteditor/fontsettings.cpp b/src/plugins/texteditor/fontsettings.cpp
index d74a13b2cc..26d3d04194 100644
--- a/src/plugins/texteditor/fontsettings.cpp
+++ b/src/plugins/texteditor/fontsettings.cpp
@@ -45,6 +45,7 @@
 static const char fontFamilyKey[] = "FontFamily";
 static const char fontSizeKey[] = "FontSize";
 static const char fontZoomKey[] = "FontZoom";
+static const char lineSpacingKey[] = "LineSpacing";
 static const char antialiasKey[] = "FontAntialias";
 static const char schemeFileNamesKey[] = "ColorSchemes";
 
@@ -56,11 +57,13 @@ static const bool DEFAULT_ANTIALIAS = true;
 namespace TextEditor {
 
 // -- FontSettings
-FontSettings::FontSettings() :
-    m_family(defaultFixedFontFamily()),
-    m_fontSize(defaultFontSize()),
-    m_fontZoom(100),
-    m_antialias(DEFAULT_ANTIALIAS)
+FontSettings::FontSettings()
+    : m_family(defaultFixedFontFamily())
+    , m_fontSize(defaultFontSize())
+    , m_fontZoom(100)
+    , m_lineSpacing(100)
+    , m_antialias(DEFAULT_ANTIALIAS)
+    , m_lineSpacingCache(0)
 {
 }
 
@@ -69,10 +72,10 @@ void FontSettings::clear()
     m_family = defaultFixedFontFamily();
     m_fontSize = defaultFontSize();
     m_fontZoom = 100;
+    m_lineSpacing = 100;
     m_antialias = DEFAULT_ANTIALIAS;
     m_scheme.clear();
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
 }
 
 static QString settingsGroup()
@@ -89,9 +92,12 @@ void FontSettings::toSettings(QSettings *s) const
     if (m_fontSize != defaultFontSize() || s->contains(QLatin1String(fontSizeKey)))
         s->setValue(QLatin1String(fontSizeKey), m_fontSize);
 
-    if (m_fontZoom!= 100 || s->contains(QLatin1String(fontZoomKey)))
+    if (m_fontZoom != 100 || s->contains(QLatin1String(fontZoomKey)))
         s->setValue(QLatin1String(fontZoomKey), m_fontZoom);
 
+    if (m_lineSpacing != 100 || s->contains(QLatin1String(lineSpacingKey)))
+        s->setValue(QLatin1String(lineSpacingKey), m_lineSpacing);
+
     if (m_antialias != DEFAULT_ANTIALIAS || s->contains(QLatin1String(antialiasKey)))
         s->setValue(QLatin1String(antialiasKey), m_antialias);
 
@@ -116,7 +122,8 @@ bool FontSettings::fromSettings(const FormatDescriptions &descriptions, const QS
 
     m_family = s->value(group + QLatin1String(fontFamilyKey), defaultFixedFontFamily()).toString();
     m_fontSize = s->value(group + QLatin1String(fontSizeKey), m_fontSize).toInt();
-    m_fontZoom= s->value(group + QLatin1String(fontZoomKey), m_fontZoom).toInt();
+    m_fontZoom = s->value(group + QLatin1String(fontZoomKey), m_fontZoom).toInt();
+    m_lineSpacing = s->value(group + QLatin1String(lineSpacingKey), m_lineSpacing).toInt();
     m_antialias = s->value(group + QLatin1String(antialiasKey), DEFAULT_ANTIALIAS).toBool();
 
     if (s->contains(group + QLatin1String(schemeFileNamesKey))) {
@@ -134,11 +141,12 @@ bool FontSettings::fromSettings(const FormatDescriptions &descriptions, const QS
 bool FontSettings::equals(const FontSettings &f) const
 {
     return m_family == f.m_family
-            && m_schemeFileName == f.m_schemeFileName
-            && m_fontSize == f.m_fontSize
-            && m_fontZoom == f.m_fontZoom
-            && m_antialias == f.m_antialias
-            && m_scheme == f.m_scheme;
+           && m_schemeFileName == f.m_schemeFileName
+           && m_fontSize == f.m_fontSize
+           && m_lineSpacing == f.m_lineSpacing
+           && m_fontZoom == f.m_fontZoom
+           && m_antialias == f.m_antialias
+           && m_scheme == f.m_scheme;
 }
 
 uint qHash(const TextStyle &textStyle)
@@ -272,6 +280,13 @@ void FontSettings::addMixinStyle(QTextCharFormat &textCharFormat,
     };
 }
 
+void FontSettings::clearCaches()
+{
+    m_formatCache.clear();
+    m_textCharFormatCache.clear();
+    m_lineSpacingCache = 0;
+}
+
 QTextCharFormat FontSettings::toTextCharFormat(TextStyles textStyles) const
 {
     auto textCharFormatIterator = m_textCharFormatCache.find(textStyles);
@@ -312,8 +327,7 @@ QString FontSettings::family() const
 void FontSettings::setFamily(const QString &family)
 {
     m_family = family;
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
 }
 
 /**
@@ -327,8 +341,7 @@ int FontSettings::fontSize() const
 void FontSettings::setFontSize(int size)
 {
     m_fontSize = size;
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
 }
 
 /**
@@ -344,6 +357,28 @@ void FontSettings::setFontZoom(int zoom)
     m_fontZoom = zoom;
     m_formatCache.clear();
     m_textCharFormatCache.clear();
+    m_lineSpacingCache = 0;
+}
+
+qreal FontSettings::lineSpacing() const
+{
+    if (qFuzzyIsNull(m_lineSpacingCache)) {
+        auto currentFont = font();
+        currentFont.setPointSize(m_fontSize * m_fontZoom / 100);
+        m_lineSpacingCache = QFontMetricsF(currentFont).lineSpacing() / 100 * m_lineSpacing;
+    }
+    return m_lineSpacingCache;
+}
+
+int FontSettings::relativeLineSpacing() const
+{
+    return m_lineSpacing;
+}
+
+void FontSettings::setRelativeLineSpacing(int relativeLineSpacing)
+{
+    m_lineSpacing = relativeLineSpacing;
+    m_lineSpacingCache = 0;
 }
 
 QFont FontSettings::font() const
@@ -364,8 +399,7 @@ bool FontSettings::antialias() const
 void FontSettings::setAntialias(bool antialias)
 {
     m_antialias = antialias;
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
 }
 
 /**
@@ -402,8 +436,7 @@ void FontSettings::setColorSchemeFileName(const QString &fileName)
 bool FontSettings::loadColorScheme(const QString &fileName,
                                    const FormatDescriptions &descriptions)
 {
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
     bool loaded = true;
     m_schemeFileName = fileName;
 
@@ -459,8 +492,7 @@ const ColorScheme &FontSettings::colorScheme() const
 void FontSettings::setColorScheme(const ColorScheme &scheme)
 {
     m_scheme = scheme;
-    m_formatCache.clear();
-    m_textCharFormatCache.clear();
+    clearCaches();
 }
 
 static QString defaultFontFamily()
diff --git a/src/plugins/texteditor/fontsettings.h b/src/plugins/texteditor/fontsettings.h
index 9447141434..0fbc80e15d 100644
--- a/src/plugins/texteditor/fontsettings.h
+++ b/src/plugins/texteditor/fontsettings.h
@@ -75,6 +75,10 @@ public:
     int fontZoom() const;
     void setFontZoom(int zoom);
 
+    qreal lineSpacing() const;
+    int relativeLineSpacing() const;
+    void setRelativeLineSpacing(int relativeLineSpacing);
+
     QFont font() const;
 
     bool antialias() const;
@@ -100,16 +104,19 @@ public:
 
 private:
     void addMixinStyle(QTextCharFormat &textCharFormat, const MixinTextStyles &mixinStyles) const;
+    void clearCaches();
 
 private:
     QString m_family;
     QString m_schemeFileName;
     int m_fontSize;
     int m_fontZoom;
+    int m_lineSpacing;
     bool m_antialias;
     ColorScheme m_scheme;
     mutable QHash<TextStyle, QTextCharFormat> m_formatCache;
     mutable QHash<TextStyles, QTextCharFormat> m_textCharFormatCache;
+    mutable qreal m_lineSpacingCache;
 };
 
 inline bool operator==(const FontSettings &f1, const FontSettings &f2) { return f1.equals(f2); }
diff --git a/src/plugins/texteditor/fontsettingspage.cpp b/src/plugins/texteditor/fontsettingspage.cpp
index 0e35cade04..41450ec8cf 100644
--- a/src/plugins/texteditor/fontsettingspage.cpp
+++ b/src/plugins/texteditor/fontsettingspage.cpp
@@ -31,9 +31,9 @@
 
 #include <coreplugin/icore.h>
 #include <utils/fileutils.h>
-#include <utils/stringutils.h>
 #include <utils/qtcassert.h>
 #include <utils/theme/theme.h>
+#include <utils/utilsicons.h>
 
 #include <QFileDialog>
 #include <QFontDatabase>
@@ -128,6 +128,11 @@ public:
 
         m_ui.antialias->setChecked(m_value.antialias());
         m_ui.zoomSpinBox->setValue(m_value.fontZoom());
+        m_ui.lineSpacingSpinBox->setValue(m_value.relativeLineSpacing());
+        m_ui.lineSpacingWarningLabel->setPixmap(Utils::Icons::WARNING.pixmap());
+        m_ui.lineSpacingWarningLabel->setToolTip(tr("A line spacing less than 100% can result in "
+                                                    "overlapping and misaligned graphics."));
+        m_ui.lineSpacingWarningLabel->setVisible(m_value.relativeLineSpacing() < 100);
 
         m_ui.schemeEdit->setFormatDescriptions(fd);
         m_ui.schemeEdit->setBaseFont(m_value.font());
@@ -143,6 +148,8 @@ public:
                 this, &FontSettingsPageWidget::fontSizeSelected);
         connect(m_ui.zoomSpinBox, QOverload<int>::of(&QSpinBox::valueChanged),
                 this, &FontSettingsPageWidget::fontZoomChanged);
+        connect(m_ui.lineSpacingSpinBox, QOverload<int>::of(&QSpinBox::valueChanged),
+                this, &FontSettingsPageWidget::lineSpacingChanged);
         connect(m_ui.antialias, &QCheckBox::toggled,
                 this, &FontSettingsPageWidget::antialiasChanged);
         connect(m_ui.schemeComboBox,
@@ -166,6 +173,7 @@ public:
     void fontSelected(const QFont &font);
     void fontSizeSelected(int index);
     void fontZoomChanged();
+    void lineSpacingChanged(const int &value);
     void antialiasChanged();
     void colorSchemeSelected(int index);
     void openCopyColorSchemeDialog();
@@ -417,6 +425,12 @@ void FontSettingsPageWidget::fontZoomChanged()
     m_value.setFontZoom(m_ui.zoomSpinBox->value());
 }
 
+void FontSettingsPageWidget::lineSpacingChanged(const int &value)
+{
+    m_value.setRelativeLineSpacing(value);
+    m_ui.lineSpacingWarningLabel->setVisible(value < 100);
+}
+
 void FontSettingsPageWidget::antialiasChanged()
 {
     m_value.setAntialias(m_ui.antialias->isChecked());
diff --git a/src/plugins/texteditor/fontsettingspage.ui b/src/plugins/texteditor/fontsettingspage.ui
index 5c61c00738..da8a9fa907 100644
--- a/src/plugins/texteditor/fontsettingspage.ui
+++ b/src/plugins/texteditor/fontsettingspage.ui
@@ -6,7 +6,7 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>639</width>
+    <width>752</width>
     <height>306</height>
    </rect>
   </property>
@@ -17,40 +17,23 @@
       <string>Font</string>
      </property>
      <layout class="QGridLayout" name="gridLayout">
-      <item row="0" column="4">
-       <widget class="QLabel" name="sizeLabel">
+      <item row="0" column="5">
+       <widget class="QComboBox" name="sizeComboBox">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
-          <horstretch>0</horstretch>
+          <horstretch>1</horstretch>
           <verstretch>0</verstretch>
          </sizepolicy>
         </property>
-        <property name="text">
-         <string>Size:</string>
-        </property>
-       </widget>
-      </item>
-      <item row="0" column="7">
-       <widget class="QLabel" name="zoomLabel">
-        <property name="text">
-         <string>Zoom:</string>
+        <property name="editable">
+         <bool>true</bool>
         </property>
        </widget>
       </item>
-      <item row="0" column="0">
-       <widget class="QLabel" name="familyLabel">
-        <property name="sizePolicy">
-         <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
-          <horstretch>0</horstretch>
-          <verstretch>0</verstretch>
-         </sizepolicy>
-        </property>
-        <property name="text">
-         <string>Family:</string>
-        </property>
-       </widget>
+      <item row="0" column="1">
+       <widget class="QFontComboBox" name="fontComboBox"/>
       </item>
-      <item row="0" column="6">
+      <item row="0" column="7">
        <spacer>
         <property name="orientation">
          <enum>Qt::Horizontal</enum>
@@ -66,7 +49,7 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="9">
+      <item row="0" column="14">
        <spacer name="horizontalSpacer">
         <property name="orientation">
          <enum>Qt::Horizontal</enum>
@@ -79,6 +62,19 @@
         </property>
        </spacer>
       </item>
+      <item row="0" column="4">
+       <widget class="QLabel" name="sizeLabel">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="text">
+         <string>Size:</string>
+        </property>
+       </widget>
+      </item>
       <item row="1" column="0" colspan="3">
        <widget class="QCheckBox" name="antialias">
         <property name="text">
@@ -86,6 +82,32 @@
         </property>
        </widget>
       </item>
+      <item row="0" column="9">
+       <widget class="QSpinBox" name="zoomSpinBox">
+        <property name="suffix">
+         <string>%</string>
+        </property>
+        <property name="minimum">
+         <number>10</number>
+        </property>
+        <property name="maximum">
+         <number>3000</number>
+        </property>
+        <property name="singleStep">
+         <number>10</number>
+        </property>
+        <property name="value">
+         <number>100</number>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="8">
+       <widget class="QLabel" name="zoomLabel">
+        <property name="text">
+         <string>Zoom:</string>
+        </property>
+       </widget>
+      </item>
       <item row="0" column="3">
        <spacer>
         <property name="orientation">
@@ -102,41 +124,61 @@
         </property>
        </spacer>
       </item>
-      <item row="0" column="8">
-       <widget class="QSpinBox" name="zoomSpinBox">
+      <item row="0" column="12">
+       <widget class="QSpinBox" name="lineSpacingSpinBox">
         <property name="suffix">
          <string>%</string>
         </property>
         <property name="minimum">
-         <number>10</number>
+         <number>50</number>
         </property>
         <property name="maximum">
          <number>3000</number>
         </property>
-        <property name="singleStep">
-         <number>10</number>
-        </property>
         <property name="value">
          <number>100</number>
         </property>
        </widget>
       </item>
-      <item row="0" column="1">
-       <widget class="QFontComboBox" name="fontComboBox"/>
-      </item>
-      <item row="0" column="5">
-       <widget class="QComboBox" name="sizeComboBox">
+      <item row="0" column="0">
+       <widget class="QLabel" name="familyLabel">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Fixed" vsizetype="Fixed">
-          <horstretch>1</horstretch>
+          <horstretch>0</horstretch>
           <verstretch>0</verstretch>
          </sizepolicy>
         </property>
-        <property name="editable">
-         <bool>true</bool>
+        <property name="text">
+         <string>Family:</string>
         </property>
        </widget>
       </item>
+      <item row="0" column="11">
+       <widget class="QLabel" name="lineSpacingLabel">
+        <property name="text">
+         <string>Line spacing:</string>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="10">
+       <spacer name="horizontalSpacer_2">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Preferred</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="0" column="13">
+       <widget class="QLabel" name="lineSpacingWarningLabel"/>
+      </item>
      </layout>
     </widget>
    </item>
@@ -200,6 +242,7 @@
   <tabstop>fontComboBox</tabstop>
   <tabstop>sizeComboBox</tabstop>
   <tabstop>zoomSpinBox</tabstop>
+  <tabstop>lineSpacingSpinBox</tabstop>
   <tabstop>antialias</tabstop>
   <tabstop>schemeComboBox</tabstop>
   <tabstop>copyButton</tabstop>
diff --git a/src/plugins/texteditor/textdocumentlayout.cpp b/src/plugins/texteditor/textdocumentlayout.cpp
index a2f292e9c7..70b63e0303 100644
--- a/src/plugins/texteditor/textdocumentlayout.cpp
+++ b/src/plugins/texteditor/textdocumentlayout.cpp
@@ -24,8 +24,13 @@
 ****************************************************************************/
 
 #include "textdocumentlayout.h"
+
+#include "fontsettings.h"
 #include "textdocument.h"
+#include "texteditorsettings.h"
+
 #include <utils/qtcassert.h>
+
 #include <QDebug>
 
 namespace TextEditor {
@@ -625,6 +630,9 @@ void TextDocumentLayout::updateMarksBlock(const QTextBlock &block)
 QRectF TextDocumentLayout::blockBoundingRect(const QTextBlock &block) const
 {
     QRectF boundingRect = QPlainTextDocumentLayout::blockBoundingRect(block);
+    if (boundingRect.isNull())
+        return boundingRect;
+    boundingRect.setHeight(TextEditorSettings::fontSettings().lineSpacing());
     if (TextBlockUserData *userData = textUserData(block))
         boundingRect.adjust(0, 0, 0, userData->additionalAnnotationHeight());
     return boundingRect;
diff --git a/src/plugins/texteditor/texteditor.cpp b/src/plugins/texteditor/texteditor.cpp
index 283f215557..aec12dc75a 100644
--- a/src/plugins/texteditor/texteditor.cpp
+++ b/src/plugins/texteditor/texteditor.cpp
@@ -1105,9 +1105,9 @@ void TextEditorWidget::print(QPrinter *printer)
     delete dlg;
 }
 
-static int foldBoxWidth(const QFontMetrics &fm)
+static int foldBoxWidth()
 {
-    const int lineSpacing = fm.lineSpacing();
+    const int lineSpacing = TextEditorSettings::fontSettings().lineSpacing();
     return lineSpacing + lineSpacing % 2 + 1;
 }
 
@@ -3604,9 +3604,9 @@ QRect TextEditorWidgetPrivate::foldBox()
     QRectF br = q->blockBoundingGeometry(begin).translated(q->contentOffset());
     QRectF er = q->blockBoundingGeometry(end).translated(q->contentOffset());
 
-    return QRect(m_extraArea->width() - foldBoxWidth(q->fontMetrics()),
+    return QRect(m_extraArea->width() - foldBoxWidth(),
                  int(br.top()),
-                 foldBoxWidth(q->fontMetrics()),
+                 foldBoxWidth(),
                  int(er.bottom() - br.top()));
 }
 
@@ -4083,7 +4083,9 @@ bool TextEditorWidgetPrivate::updateAnnotationBounds(TextBlockUserData *blockUse
 {
     const bool additionalHeightNeeded = annotationsVisible
             && m_displaySettings.m_annotationAlignment == AnnotationAlignment::BetweenLines;
-    const int additionalHeight = additionalHeightNeeded ? q->fontMetrics().lineSpacing() : 0;
+    const int additionalHeight = additionalHeightNeeded
+                                     ? TextEditorSettings::fontSettings().lineSpacing()
+                                     : 0;
     if (blockUserData->additionalAnnotationHeight() == additionalHeight)
         return false;
     blockUserData->setAdditionalAnnotationHeight(additionalHeight);
@@ -4124,7 +4126,7 @@ void TextEditorWidgetPrivate::updateLineAnnotation(const PaintEventData &data,
         return mark1->priority() > mark2->priority();
     });
 
-    const qreal itemOffset = q->fontMetrics().lineSpacing();
+    const qreal itemOffset = blockData.boundingRect.height();
     const qreal initialOffset = m_displaySettings.m_annotationAlignment == AnnotationAlignment::BetweenLines ? itemOffset / 2 : itemOffset * 2;
     const qreal minimalContentWidth = q->fontMetrics().horizontalAdvance('X')
             * m_displaySettings.m_minimalAnnotationContent;
@@ -5018,7 +5020,7 @@ int TextEditorWidget::extraAreaWidth(int *markWidthPtr) const
     int markWidth = 0;
 
     if (d->m_marksVisible) {
-        markWidth += documentLayout->maxMarkWidthFactor * fm.lineSpacing() + 2;
+        markWidth += documentLayout->maxMarkWidthFactor * TextEditorSettings::fontSettings().lineSpacing() + 2;
 
 //     if (documentLayout->doubleMarkCount)
 //         markWidth += fm.lineSpacing() / 3;
@@ -5033,7 +5035,7 @@ int TextEditorWidget::extraAreaWidth(int *markWidthPtr) const
     space += 4;
 
     if (d->m_codeFoldingVisible)
-        space += foldBoxWidth(fm);
+        space += foldBoxWidth();
 
     if (viewportMargins() != QMargins{isLeftToRight() ? space : 0, 0, isLeftToRight() ? 0 : space, 0})
         d->slotUpdateExtraAreaWidth(space);
@@ -5059,9 +5061,9 @@ struct Internal::ExtraAreaPaintEventData
         , selectionStart(editor->textCursor().selectionStart())
         , selectionEnd(editor->textCursor().selectionEnd())
         , fontMetrics(d->m_extraArea->font())
-        , lineSpacing(fontMetrics.lineSpacing())
+        , lineSpacing(TextEditorSettings::fontSettings().lineSpacing())
         , markWidth(d->m_marksVisible ? lineSpacing : 0)
-        , collapseColumnWidth(d->m_codeFoldingVisible ? foldBoxWidth(fontMetrics) : 0)
+        , collapseColumnWidth(d->m_codeFoldingVisible ? foldBoxWidth() : 0)
         , extraAreaWidth(d->m_extraArea->width() - collapseColumnWidth)
         , currentLineNumberFormat(
               editor->textDocument()->fontSettings().toTextCharFormat(C_CURRENT_LINE_NUMBER))
@@ -5185,7 +5187,7 @@ void TextEditorWidgetPrivate::paintCodeFolding(QPainter &painter,
     bool hovered = blockNumber >= extraAreaHighlightFoldBlockNumber
             && blockNumber <= extraAreaHighlightFoldEndBlockNumber;
 
-    int boxWidth = foldBoxWidth(data.fontMetrics);
+    int boxWidth = foldBoxWidth();
     if (hovered) {
         int itop = qRound(blockBoundingRect.top());
         int ibottom = qRound(blockBoundingRect.bottom());
@@ -5558,8 +5560,10 @@ void TextEditorWidget::mouseMoveEvent(QMouseEvent *e)
                     if (cursor.positionInBlock() == cursor.block().length()-1)
                         column += (e->pos().x() - cursorRect().center().x()) / QFontMetricsF(font()).horizontalAdvance(QLatin1Char(' '));
                     int block = cursor.blockNumber();
-                    if (block == blockCount() - 1)
-                        block += (e->pos().y() - cursorRect().center().y()) / QFontMetricsF(font()).lineSpacing();
+                    if (block == blockCount() - 1) {
+                        block += (e->pos().y() - cursorRect().center().y())
+                                 / TextEditorSettings::fontSettings().lineSpacing();
+                    }
                     d->enableBlockSelection(block, column, block, column);
                 }
             } else {
@@ -5609,8 +5613,11 @@ void TextEditorWidget::mousePressEvent(QMouseEvent *e)
             if (cursor.positionInBlock() == cursor.block().length()-1)
                 column += (e->pos().x() - cursorRect(cursor).center().x()) / QFontMetricsF(font()).horizontalAdvance(QLatin1Char(' '));
             int block = cursor.blockNumber();
-            if (block == blockCount() - 1)
-                block += (e->pos().y() - cursorRect(cursor).center().y()) / QFontMetricsF(font()).lineSpacing();
+            if (block == blockCount() - 1) {
+                block += (e->pos().y() - cursorRect(cursor).center().y())
+                         / TextEditorSettings::fontSettings().lineSpacing();
+            }
+
             if (d->m_inBlockSelectionMode) {
                 d->m_blockSelection.positionBlock = block;
                 d->m_blockSelection.positionColumn = column;
@@ -5784,7 +5791,7 @@ void TextEditorWidget::updateFoldingHighlight(const QPoint &pos)
     const int highlightBlockNumber = d->extraAreaHighlightFoldedBlockNumber;
     d->extraAreaHighlightFoldedBlockNumber = -1;
 
-    if (pos.x() > extraArea()->width() - foldBoxWidth(fontMetrics())) {
+    if (pos.x() > extraArea()->width() - foldBoxWidth()) {
         d->extraAreaHighlightFoldedBlockNumber = cursor.blockNumber();
     } else if (d->m_displaySettings.m_highlightBlocks) {
         QTextCursor cursor = textCursor();
@@ -5827,7 +5834,7 @@ void TextEditorWidget::extraAreaMouseEvent(QMouseEvent *e)
             int dist = (e->pos() - d->m_markDragStart).manhattanLength();
             if (dist > QApplication::startDragDistance()) {
                 d->m_markDragging = true;
-                const int height = fontMetrics().lineSpacing() - 1;
+                const int height = TextEditorSettings::fontSettings().lineSpacing() - 1;
                 const int width = int(.5 + height * d->m_dragMark->widthFactor());
                 d->m_markDragCursor = QCursor(d->m_dragMark->icon().pixmap({height, width}));
                 d->m_dragMark->setVisible(false);
@@ -5845,7 +5852,7 @@ void TextEditorWidget::extraAreaMouseEvent(QMouseEvent *e)
 
     if (e->type() == QEvent::MouseButtonPress || e->type() == QEvent::MouseButtonDblClick) {
         if (e->button() == Qt::LeftButton) {
-            int boxWidth = foldBoxWidth(fontMetrics());
+            int boxWidth = foldBoxWidth();
             if (d->m_codeFoldingVisible && e->pos().x() > extraArea()->width() - boxWidth) {
                 if (!cursor.block().next().isVisible()) {
                     d->toggleBlockVisible(cursor.block());
@@ -6372,7 +6379,7 @@ void TextEditorWidgetPrivate::adjustScrollBarRanges()
 {
     if (!m_highlightScrollBarController)
         return;
-    const double lineSpacing = QFontMetricsF(q->font()).lineSpacing();
+    const double lineSpacing = TextEditorSettings::fontSettings().lineSpacing();
     if (lineSpacing == 0)
         return;