Start the implementation of in-place recoding for images

Currently, with the graphics system raster, converting from images
to QPixmap often needs to allocate a new image to convert the right
format.

For example, for an image in ARGB32 of 10 mbytes, we need to allocate
a second image of 10 mbytes in ARGB32_PM to convert the source image
in the right format for pixmap.

This can create a hight peak of memory, and is a bit slower
than it should.

This patch introduce in-place conversion of images when they are
loaded with QPixmap::loadFromData().
The images are loaded in their default format by QImageReader,
and are then converted in-place, trying to reduce memory
allocations.

Reviewed-by: Samuel Rødal

1 files changed, 3 insertions, 0 deletions

diff --git a/src/gui/image/qpixmap_raster_p.h b/src/gui/image/qpixmap_raster_p.h
index 6cdd3d7101..d7e3f85ed5 100644
--- a/src/gui/image/qpixmap_raster_p.h
+++ b/src/gui/image/qpixmap_raster_p.h
@@ -72,6 +72,7 @@ public:
 
     void resize(int width, int height);
     void fromFile(const QString &filename, Qt::ImageConversionFlags flags);
+    bool fromData(const uchar *buffer, uint len, const char *format, Qt::ImageConversionFlags flags);
     void fromImage(const QImage &image, Qt::ImageConversionFlags flags);
 
     bool scroll(int dx, int dy, const QRect &rect);
@@ -85,6 +86,8 @@ public:
 
 protected:
     int metric(QPaintDevice::PaintDeviceMetric metric) const;
+    void createPixmapForImage(QImage &sourceImage, Qt::ImageConversionFlags flags, bool inPlace);
+    void setImage(const QImage &image);
     QImage image;
 
 private: