Use OpenType font weights

Task-number: QTBUG-42248
Change-Id: Icdb301b27d6699c2b842c4563fbef9df73c23cbc
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

3 files changed, 77 insertions, 2 deletions

diff --git a/src/tools/uic/cpp/cppwriteinitialization.cpp b/src/tools/uic/cpp/cppwriteinitialization.cpp
index 29c054bc22..2a3c9bdd70 100644
--- a/src/tools/uic/cpp/cppwriteinitialization.cpp
+++ b/src/tools/uic/cpp/cppwriteinitialization.cpp
@@ -1623,8 +1623,57 @@ QString WriteInitialization::writeFontProperties(const DomFont *f)
             << language::boolValue(f->elementUnderline()) << ')' << language::eol;
     }
     if (f->hasElementWeight() && f->elementWeight() > 0) {
-        m_output << m_indent << fontName << ".setWeight("
-            << f->elementWeight() << ")" << language::eol;
+        int weight = f->elementWeight();
+        if (!f->hasAttributeScale()) {
+            // Convert from old Qt scale to OpenType scale.
+            // (not a linear conversion, so we adapt the known values and approximate the others).
+            // Note that we cannot use qt_legacyToOpenTypeWeight from qfont_p.h here due to
+            // dependency issues.
+
+            switch (f->elementWeight()) {
+            case 0:
+                weight = 100;
+                break;
+            case 12:
+                weight = 200;
+                break;
+            case 25:
+                weight = 300;
+                break;
+            case 50:
+                weight = 400;
+                break;
+            case 57:
+                weight = 500;
+                break;
+            case 63:
+                weight = 600;
+                break;
+            case 75:
+                weight = 700;
+                break;
+            case 81:
+                weight = 800;
+                break;
+            case 87:
+                weight = 900;
+                break;
+            default:
+                weight *= 8;
+                weight += 100;
+                break;
+            }
+        }
+
+        switch (language::language()) {
+        case Language::Cpp:
+            m_output << m_indent << fontName << ".setWeight(QFont::Weight(" << weight << "))"
+                     << language::eol;
+            break;
+        case Language::Python:
+            m_output << m_indent << fontName << ".setWeight(" << weight << ")" << language::eol;
+            break;
+        }
     }
     if (f->hasElementStrikeOut()) {
          m_output << m_indent << fontName << ".setStrikeOut("
diff --git a/src/tools/uic/ui4.cpp b/src/tools/uic/ui4.cpp
index a155df9b6c..8a535582b9 100644
--- a/src/tools/uic/ui4.cpp
+++ b/src/tools/uic/ui4.cpp
@@ -3099,6 +3099,16 @@ DomFont::~DomFont() = default;
 
 void DomFont::read(QXmlStreamReader &reader)
 {
+    const QXmlStreamAttributes &attributes = reader.attributes();
+    for (const QXmlStreamAttribute &attribute : attributes) {
+        const auto name = attribute.name();
+        if (name == QLatin1String("scale")) {
+            setAttributeScale(attribute.value().toString());
+            continue;
+        }
+        reader.raiseError(QLatin1String("Unexpected attribute ") + name);
+    }
+
     while (!reader.hasError()) {
         switch (reader.readNext()) {
         case QXmlStreamReader::StartElement : {
@@ -3158,6 +3168,9 @@ void DomFont::write(QXmlStreamWriter &writer, const QString &tagName) const
 {
     writer.writeStartElement(tagName.isEmpty() ? QStringLiteral("font") : tagName.toLower());
 
+    if (hasAttributeScale())
+        writer.writeAttribute(QStringLiteral("scale"), attributeScale());
+
     if (m_children & Family)
         writer.writeTextElement(QStringLiteral("family"), m_family);
 
diff --git a/src/tools/uic/ui4.h b/src/tools/uic/ui4.h
index a5ac51f521..41f11644bd 100644
--- a/src/tools/uic/ui4.h
+++ b/src/tools/uic/ui4.h
@@ -1619,6 +1619,16 @@ public:
     void read(QXmlStreamReader &reader);
     void write(QXmlStreamWriter &writer, const QString &tagName = QString()) const;
 
+    // attribute accessors
+    inline bool hasAttributeScale() const { return m_has_attr_scale; }
+    inline QString attributeScale() const { return m_attr_scale; }
+    inline void setAttributeScale(const QString &a)
+    {
+        m_attr_scale = a;
+        m_has_attr_scale = true;
+    }
+    inline void clearAttributeScale() { m_has_attr_scale = false; }
+
     // child element accessors
     inline QString elementFamily() const { return m_family; }
     void setElementFamily(const QString &a);
@@ -1671,6 +1681,9 @@ public:
     void clearElementKerning();
 
 private:
+    // attribute data
+    QString m_attr_scale;
+    bool m_has_attr_scale = false;
 
     // child element data
     uint m_children = 0;