QmlDesigner: Fix font preview tooltip image

The preview tooltip was recently reduced in size, but font previews
were still being rendered the old size and scaled down, degrading
image quality. The new default size is bit too small to render the
sample text of fonts nicely, so added an option to set unscaled image
to the tooltip, allowing us to use twice as wide preview images for
fonts.

Fixes: QDS-6486
Change-Id: Ieaabfbea11e47509de7cd6aed93464d8595ea541
Reviewed-by: Samuel Ghinet <samuel.ghinet@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/plugins/qmldesigner/components/assetslibrary/assetslibrarymodel.cpp

@@ -253,11 +253,8 @@ const QStringList &AssetsLibraryModel::supportedTexture3DSuffixes()
     return retList;
 }
 
-AssetsLibraryModel::AssetsLibraryModel(SynchronousImageCache &fontImageCache,
+AssetsLibraryModel::AssetsLibraryModel(Utils::FileSystemWatcher *fileSystemWatcher, QObject *parent)
-                                               Utils::FileSystemWatcher *fileSystemWatcher,
-                                               QObject *parent)
     : QAbstractListModel(parent)
-    , m_fontImageCache(fontImageCache)
     , m_fileSystemWatcher(fileSystemWatcher)
 {
     // add role names

src/plugins/qmldesigner/components/assetslibrary/assetslibrarymodel.h

@@ -47,9 +47,7 @@ class AssetsLibraryModel : public QAbstractListModel
     Q_PROPERTY(bool isEmpty READ isEmpty WRITE setIsEmpty NOTIFY isEmptyChanged)
 
 public:
-    AssetsLibraryModel(QmlDesigner::SynchronousImageCache &fontImageCache,
+    AssetsLibraryModel(Utils::FileSystemWatcher *fileSystemWatcher, QObject *parent = nullptr);
-                           Utils::FileSystemWatcher *fileSystemWatcher,
-                           QObject *parent = nullptr);
 
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
     int rowCount(const QModelIndex &parent = QModelIndex()) const override;
@@ -97,7 +95,6 @@ private:
 
     void setIsEmpty(bool empty);
 
-    SynchronousImageCache &m_fontImageCache;
     QHash<QString, QPair<QDateTime, QIcon>> m_iconCache;
 
     QString m_searchText;

src/plugins/qmldesigner/components/assetslibrary/assetslibrarywidget.cpp

@@ -117,7 +117,7 @@ AssetsLibraryWidget::AssetsLibraryWidget(AsynchronousImageCache &imageCache,
     , m_fontImageCache(synchronousFontImageCache)
     , m_assetsIconProvider(new AssetsLibraryIconProvider(synchronousFontImageCache))
     , m_fileSystemWatcher(new Utils::FileSystemWatcher(this))
-    , m_assetsModel(new AssetsLibraryModel(synchronousFontImageCache, m_fileSystemWatcher, this))
+    , m_assetsModel(new AssetsLibraryModel(m_fileSystemWatcher, this))
     , m_assetsWidget(new QQuickWidget(this))
     , m_imageCache{imageCache}
 {
@@ -130,11 +130,13 @@ AssetsLibraryWidget::AssetsLibraryWidget(AsynchronousImageCache &imageCache,
     m_assetsWidget->installEventFilter(this);
 
     m_fontPreviewTooltipBackend = std::make_unique<PreviewTooltipBackend>(asynchronousFontImageCache);
+    // We want font images to have custom size, so don't scale them in the tooltip
+    m_fontPreviewTooltipBackend->setScaleImage(false);
     // Note: Though the text specified here appears in UI, it shouldn't be translated, as it's
     // a commonly used sentence to preview the font glyphs in latin fonts.
     // For fonts that do not have latin glyphs, the font family name will have to suffice for preview.
     m_fontPreviewTooltipBackend->setAuxiliaryData(
-        ImageCache::FontCollectorSizeAuxiliaryData{QSize{300, 300},
+        ImageCache::FontCollectorSizeAuxiliaryData{QSize{300, 150},
                                                    Theme::getColor(Theme::DStextColor).name(),
                                                    QStringLiteral("The quick brown fox jumps\n"
                                                                   "over the lazy dog\n"

src/plugins/qmldesigner/components/previewtooltip/previewimagetooltip.cpp

@@ -62,10 +62,16 @@ void PreviewImageTooltip::setInfo(const QString &info)
     m_ui->infoLabel->setText(info);
 }
 
-void PreviewImageTooltip::setImage(const QImage &image)
+void PreviewImageTooltip::setImage(const QImage &image, bool scale)
 {
-    m_ui->imageLabel->setPixmap(QPixmap::fromImage({image}).scaled(m_ui->imageLabel->width(),
+    QPixmap pm = QPixmap::fromImage({image});
+    if (scale) {
+        m_ui->imageLabel->setPixmap(pm.scaled(m_ui->imageLabel->width(),
                                               m_ui->imageLabel->height(),
                                               Qt::KeepAspectRatio));
+    } else {
+        m_ui->imageLabel->setPixmap(pm);
+    }
 }
+
 }

src/plugins/qmldesigner/components/previewtooltip/previewimagetooltip.h

@@ -46,7 +46,7 @@ public:
     void setName(const QString &name);
     void setPath(const QString &path);
     void setInfo(const QString &info);
-    void setImage(const QImage &pixmap);
+    void setImage(const QImage &image, bool scale = true);
 
 private:
     std::unique_ptr<Ui::PreviewImageTooltip> m_ui;

src/plugins/qmldesigner/components/previewtooltip/previewtooltipbackend.cpp

@@ -55,10 +55,10 @@ void PreviewTooltipBackend::showTooltip()
 
     m_cache.requestImage(
         m_path,
-        [tooltip = QPointer<PreviewImageTooltip>(m_tooltip.get())](const QImage &image) {
+        [tooltip = QPointer<PreviewImageTooltip>(m_tooltip.get()), scaleImage = m_scaleImage](const QImage &image) {
-            QMetaObject::invokeMethod(tooltip, [tooltip, image] {
+            QMetaObject::invokeMethod(tooltip, [tooltip, image, scaleImage] {
                 if (tooltip) {
-                    tooltip->setImage(image);
+                    tooltip->setImage(image, scaleImage);
                     tooltip->show();
                 }
             });
@@ -126,9 +126,10 @@ QString PreviewTooltipBackend::name() const
 
 void PreviewTooltipBackend::setName(const QString &name)
 {
+    if (m_name != name) {
         m_name = name;
-    if (m_name != name)
         emit nameChanged();
+    }
 }
 
 QString PreviewTooltipBackend::path() const
@@ -138,9 +139,10 @@ QString PreviewTooltipBackend::path() const
 
 void PreviewTooltipBackend::setPath(const QString &path)
 {
+    if (m_path != path) {
         m_path = path;
-    if (m_path != path)
         emit pathChanged();
+    }
 }
 
 QString PreviewTooltipBackend::info() const
@@ -150,9 +152,10 @@ QString PreviewTooltipBackend::info() const
 
 void PreviewTooltipBackend::setInfo(const QString &info)
 {
+    if (m_info != info) {
         m_info = info;
-    if (m_info != info)
         emit infoChanged();
+    }
 }
 
 QString PreviewTooltipBackend::extraId() const
@@ -163,9 +166,23 @@ QString PreviewTooltipBackend::extraId() const
 // Sets the imageCache extraId hint. Valid content depends on image cache collector used.
 void PreviewTooltipBackend::setExtraId(const QString &extraId)
 {
+    if (m_extraId != extraId) {
         m_extraId = extraId;
-    if (m_extraId != extraId)
         emit extraIdChanged();
+    }
+}
+
+bool PreviewTooltipBackend::scaleImage() const
+{
+    return m_scaleImage;
+}
+
+void PreviewTooltipBackend::setScaleImage(bool scale)
+{
+    if (m_scaleImage != scale) {
+        m_scaleImage = scale;
+        emit scaleImageChanged();
+    }
 }
 
 } // namespace QmlDesigner

src/plugins/qmldesigner/components/previewtooltip/previewtooltipbackend.h

@@ -45,6 +45,7 @@ class PreviewTooltipBackend : public QObject
     Q_PROPERTY(QString path READ path WRITE setPath NOTIFY pathChanged)
     Q_PROPERTY(QString info READ info WRITE setInfo NOTIFY infoChanged)
     Q_PROPERTY(QString extraId READ extraId WRITE setExtraId NOTIFY extraIdChanged)
+    Q_PROPERTY(bool scaleImage READ scaleImage WRITE setScaleImage NOTIFY scaleImageChanged)
 
 public:
     PreviewTooltipBackend(AsynchronousImageCache &cache);
@@ -62,6 +63,8 @@ public:
     void setInfo(const QString &info);
     QString extraId() const;
     void setExtraId(const QString &extraId);
+    bool scaleImage() const;
+    void setScaleImage(bool scale);
 
     bool isVisible() const;
 
@@ -75,12 +78,14 @@ signals:
     void pathChanged();
     void infoChanged();
     void extraIdChanged();
+    void scaleImageChanged();
 
 private:
     QString m_name;
     QString m_path;
     QString m_info;
     QString m_extraId;
+    bool m_scaleImage = true;
     std::unique_ptr<PreviewImageTooltip> m_tooltip;
     ImageCache::AuxiliaryData m_auxiliaryData;
     AsynchronousImageCache &m_cache;

src/plugins/qmldesigner/designercore/imagecache/imagecachefontcollector.cpp

@@ -131,7 +131,7 @@ void ImageCacheFontCollector::start(Utils::SmallStringView name,
         auto &&auxiliaryData = Utils::get<ImageCache::FontCollectorSizeAuxiliaryData>(auxiliaryDataValue);
         QColor textColor = auxiliaryData.colorName;
         QSize size = auxiliaryData.size;
-        QString text = font.family() + "\n\n" + auxiliaryData.text;
+        QString text = font.family() + "\n" + auxiliaryData.text;
 
         QImage image = createFontImage(text, textColor, font, size);