Match QFont::ContextFontMerging with Qt Quick API

While we don't support all style strategy flags in
Qt Quick, we do support selected ones as bools.
QFont::ContextFontMerging is useful to be able to
set per Text element, so it should be exposed through
the QML APIs.

Task-number: QTBUG-121131
Change-Id: If28a065aefc4e2043e830e31356b8bd98f6d4cd8
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>

6 files changed, 59 insertions, 0 deletions

diff --git a/src/quick/items/qquicktext.cpp b/src/quick/items/qquicktext.cpp
index 5f85fa2080..ec042010d0 100644
--- a/src/quick/items/qquicktext.cpp
+++ b/src/quick/items/qquicktext.cpp
@@ -1853,6 +1853,27 @@ QQuickText::~QQuickText()
     \sa QFont::setFeature()
 //! [qml-font-features]
 */
+
+/*!
+    \qmlproperty object QtQuick::Text::font.contextFontMerging
+    \since 6.8
+
+//! [qml-font-context-font-merging]
+    If the selected font does not contain a certain character, Qt automatically chooses a
+    similar-looking fallback font that contains the character. By default this is done on a
+    character-by-character basis.
+
+    This means that in certain uncommon cases, many different fonts may be used to represent one
+    string of text even if it's in the same script. Setting \c contextFontMerging to true will try
+    finding the fallback font that matches the largest subset of the input string instead. This
+    will be more expensive for strings where missing glyphs occur, but may give more consistent
+    results. By default, \c contextFontMerging is \c{false}.
+
+    \sa QFont::StyleStrategy
+//! [qml-font-context-font-merging]
+*/
+
+
 QFont QQuickText::font() const
 {
     Q_D(const QQuickText);
diff --git a/src/quick/items/qquicktextedit.cpp b/src/quick/items/qquicktextedit.cpp
index 22bbd6e05b..02b34a6671 100644
--- a/src/quick/items/qquicktextedit.cpp
+++ b/src/quick/items/qquicktextedit.cpp
@@ -376,6 +376,13 @@ QString QQuickTextEdit::text() const
 */
 
 /*!
+    \qmlproperty object QtQuick::TextEdit::font.contextFontMerging
+    \since 6.8
+
+    \include qquicktext.cpp qml-font-context-font-merging
+*/
+
+/*!
     \qmlproperty string QtQuick::TextEdit::text
 
     The text to display.  If the text format is AutoText the text edit will
diff --git a/src/quick/items/qquicktextinput.cpp b/src/quick/items/qquicktextinput.cpp
index ef00451788..c013595f45 100644
--- a/src/quick/items/qquicktextinput.cpp
+++ b/src/quick/items/qquicktextinput.cpp
@@ -403,6 +403,13 @@ QString QQuickTextInputPrivate::realText() const
 
     \include qquicktext.cpp qml-font-features
 */
+
+/*!
+    \qmlproperty object QtQuick::TextInput::font.contextFontMerging
+    \since 6.8
+
+    \include qquicktext.cpp qml-font-context-font-merging
+*/
 QFont QQuickTextInput::font() const
 {
     Q_D(const QQuickTextInput);
diff --git a/src/quick/util/qquickpath.cpp b/src/quick/util/qquickpath.cpp
index 29c09abee2..8995c64d0b 100644
--- a/src/quick/util/qquickpath.cpp
+++ b/src/quick/util/qquickpath.cpp
@@ -2809,6 +2809,13 @@ void QQuickPathMultiline::addToPath(QPainterPath &path, const QQuickPathData &)
 
     \include qquicktext.cpp qml-font-features
 */
+
+/*!
+    \qmlproperty object QtQuick::PathText::font.contextFontMerging
+    \since 6.8
+
+    \include qquicktext.cpp qml-font-context-font-merging
+*/
 void QQuickPathText::updatePath() const
 {
     if (!_path.isEmpty())
diff --git a/src/quick/util/qquickvaluetypes.cpp b/src/quick/util/qquickvaluetypes.cpp
index 4f4f893d83..350f55e143 100644
--- a/src/quick/util/qquickvaluetypes.cpp
+++ b/src/quick/util/qquickvaluetypes.cpp
@@ -1080,6 +1080,19 @@ QVariantMap QQuickFontValueType::features() const
     return ret;
 }
 
+bool QQuickFontValueType::contextFontMerging() const
+{
+    return (v.styleStrategy() & QFont::ContextFontMerging) != 0;
+}
+
+void QQuickFontValueType::setContextFontMerging(bool enable)
+{
+    if (enable)
+        v.setStyleStrategy(static_cast<QFont::StyleStrategy>(v.styleStrategy() | QFont::ContextFontMerging));
+    else
+        v.setStyleStrategy(static_cast<QFont::StyleStrategy>(v.styleStrategy() & ~QFont::ContextFontMerging));
+}
+
 QVariant QQuickColorSpaceValueType::create(const QJSValue &params)
 {
     if (!params.isObject())
diff --git a/src/quick/util/qquickvaluetypes_p.h b/src/quick/util/qquickvaluetypes_p.h
index 08491c633b..c203d12fab 100644
--- a/src/quick/util/qquickvaluetypes_p.h
+++ b/src/quick/util/qquickvaluetypes_p.h
@@ -409,6 +409,7 @@ class Q_QUICK_EXPORT QQuickFontValueType
     Q_PROPERTY(bool preferShaping READ preferShaping WRITE setPreferShaping FINAL)
     Q_PROPERTY(QVariantMap features READ features WRITE setFeatures FINAL)
     Q_PROPERTY(QVariantMap variableAxes READ variableAxes WRITE setVariableAxes FINAL)
+    Q_PROPERTY(bool contextFontMerging READ contextFontMerging WRITE setContextFontMerging FINAL)
 
     QML_VALUE_TYPE(font)
     QML_FOREIGN(QFont)
@@ -475,6 +476,9 @@ public:
     QVariantMap variableAxes() const;
     void setVariableAxes(const QVariantMap &variableAxes);
 
+    bool contextFontMerging() const;
+    void setContextFontMerging(bool b);
+
     operator QFont() const { return v; }
 };