Add a private function for conversion a QPixmap into a VGImage

Custom OpenVG pixmap filters written by users will need to access
the VGImage form of a QPixmap.  The qPixmapToVGImage() function
is provided for this purpose, as a private API.

Reviewed-by: Sarah Smith

1 files changed, 25 insertions, 0 deletions

diff --git a/src/openvg/qpixmapdata_vg.cpp b/src/openvg/qpixmapdata_vg.cpp
index 90fd9a5882..6f2024fa1e 100644
--- a/src/openvg/qpixmapdata_vg.cpp
+++ b/src/openvg/qpixmapdata_vg.cpp
@@ -341,4 +341,29 @@ QImage::Format QVGPixmapData::sourceFormat() const
     return QImage::Format_ARGB32_Premultiplied;
 }
 
+/*
+    \internal
+
+    Returns the VGImage that is storing the contents of \a pixmap.
+    Returns VG_INVALID_HANDLE if \a pixmap is not owned by the OpenVG
+    graphics system or \a pixmap is invalid.
+
+    This function is typically used to access the backing store
+    for a pixmap when executing raw OpenVG calls.  It must only
+    be used when a QPainter is active and the OpenVG paint engine
+    is in use by the QPainter.
+
+    \sa {QtOpenVG Module}
+*/
+Q_OPENVG_EXPORT VGImage qPixmapToVGImage(const QPixmap& pixmap)
+{
+    QPixmapData *pd = pixmap.pixmapData();
+    if (pd->classId() == QPixmapData::OpenVGClass) {
+        QVGPixmapData *vgpd = static_cast<QVGPixmapData *>(pd);
+        if (vgpd->isValid())
+            return vgpd->toVGImage();
+    }
+    return VG_INVALID_HANDLE;
+}
+
 QT_END_NAMESPACE