QImage: optimize convertWithPalette()

The old code got a QMap serialized as a QString and parsed it to
re-create the same map.

Just copy the map.

Change-Id: Ic71b9fa9d822eab53fe37dfb4d76223cd69ac057
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

3 files changed, 5 insertions, 6 deletions

diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index 2646d298e9..499c527cfc 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -2149,12 +2149,7 @@ static QImage convertWithPalette(const QImage &src, QImage::Format format,
     QImage dest(src.size(), format);
     dest.setColorTable(clut);
 
-    QString textsKeys = src.text();
-    const auto textKeyList = textsKeys.splitRef(QLatin1Char('\n'), Qt::SkipEmptyParts);
-    for (const auto &textKey : textKeyList) {
-        const auto textKeySplitted = textKey.split(QLatin1String(": "));
-        dest.setText(textKeySplitted[0].toString(), textKeySplitted[1].toString());
-    }
+    QImageData::get(dest)->text = QImageData::get(src)->text;
 
     int h = src.height();
     int w = src.width();
diff --git a/src/gui/image/qimage.h b/src/gui/image/qimage.h
index 56824e5ee7..b11aa9d9d0 100644
--- a/src/gui/image/qimage.h
+++ b/src/gui/image/qimage.h
@@ -385,6 +385,7 @@ private:
     friend class QRasterPlatformPixmap;
     friend class QBlittablePlatformPixmap;
     friend class QPixmapCacheEntry;
+    friend struct QImageData;
 
 public:
     typedef QImageData * DataPtr;
diff --git a/src/gui/image/qimage_p.h b/src/gui/image/qimage_p.h
index 0930955f5a..03ec43eaf7 100644
--- a/src/gui/image/qimage_p.h
+++ b/src/gui/image/qimage_p.h
@@ -69,6 +69,9 @@ struct Q_GUI_EXPORT QImageData {        // internal image data
     static QImageData *create(const QSize &size, QImage::Format format);
     static QImageData *create(uchar *data, int w, int h,  int bpl, QImage::Format format, bool readOnly, QImageCleanupFunction cleanupFunction = nullptr, void *cleanupInfo = nullptr);
 
+    static QImageData *get(QImage &img) noexcept { return img.d; }
+    static const QImageData *get(const QImage &img) noexcept { return img.d; }
+
     QAtomicInt ref;
 
     int width;