Added native image handle provider support in pixmaps on openvg.

QNativeImageHandleProvider is a thin interface consisting of get()
and release() functions. Pixmaps constructed with such a provider
will call these functions to acquire and release a native handle,
e.g. a CFbsBitmap or RSgImage pointer in case of Symbian. The behavior
is largely similar to constructing pixmaps via fromSymbianCFbsBitmap
or fromSymbianRSgImage, with the exception of pixmap hibernation:
release() (and subsequently get()) is guaranteed to be called also
in case of hibernation, allowing more fine-grained tracking of
the usage and lifetime of image data.

Task-number: QT-4632
Reviewed-by: Jani Hautakangas

1 files changed, 34 insertions, 3 deletions

diff --git a/src/openvg/qpixmapdata_vg.cpp b/src/openvg/qpixmapdata_vg.cpp
index 47de5ab..3f67c79 100644
--- a/src/openvg/qpixmapdata_vg.cpp
+++ b/src/openvg/qpixmapdata_vg.cpp
@@ -50,6 +50,7 @@
 #include <QBuffer>
 #include <QImageReader>
 #include <QtGui/private/qimage_p.h>
+#include <QtGui/private/qnativeimagehandleprovider_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -66,6 +67,10 @@ QVGPixmapData::QVGPixmapData(PixelType type)
     inImagePool = false;
     inLRU = false;
     failedToAlloc = false;
+#if defined(Q_OS_SYMBIAN)
+    nativeImageHandleProvider = 0;
+    nativeImageHandle = 0;
+#endif
 #if !defined(QT_NO_EGL)
     context = 0;
     qt_vg_register_pixmap(this);
@@ -98,6 +103,10 @@ void QVGPixmapData::destroyImages()
     vgImage = VG_INVALID_HANDLE;
     vgImageOpacity = VG_INVALID_HANDLE;
     inImagePool = false;
+
+#if defined(Q_OS_SYMBIAN)
+    releaseNativeImageHandle();
+#endif
 }
 
 void QVGPixmapData::destroyImageAndContext()
@@ -120,6 +129,10 @@ void QVGPixmapData::destroyImageAndContext()
 #else
         destroyImages();
 #endif
+    } else {
+#if defined(Q_OS_SYMBIAN)
+        releaseNativeImageHandle();
+#endif
     }
 #if !defined(QT_NO_EGL)
     if (context) {
@@ -343,6 +356,12 @@ VGImage QVGPixmapData::toVGImage()
     else if (recreate)
         cachedOpacity = -1.0f;  // Force opacity image to be refreshed later.
 
+#if defined(Q_OS_SYMBIAN)
+    if (recreate && nativeImageHandleProvider && !nativeImageHandle) {
+        createFromNativeImageHandleProvider();
+    }
+#endif
+
     if (vgImage == VG_INVALID_HANDLE) {
         vgImage = QVGImagePool::instance()->createImageForPixmap
             (qt_vg_image_to_vg_format(source.format()), w, h, VG_IMAGE_QUALITY_FASTER, this);
@@ -427,9 +446,16 @@ void QVGPixmapData::detachImageFromPool()
 
 void QVGPixmapData::hibernate()
 {
-    // If the image was imported (e.g, from an SgImage under Symbian),
-    // then we cannot copy it back to main memory for storage.
-    if (vgImage != VG_INVALID_HANDLE && source.isNull())
+    // If the image was imported (e.g, from an SgImage under Symbian), then
+    // skip the hibernation, there is no sense in copying it back to main
+    // memory because the data is most likely shared between several processes.
+    bool skipHibernate = (vgImage != VG_INVALID_HANDLE && source.isNull());
+#if defined(Q_OS_SYMBIAN)
+    // However we have to proceed normally if the image was retrieved via
+    // a handle provider.
+    skipHibernate &= !nativeImageHandleProvider;
+#endif
+    if (skipHibernate)
         return;
 
     forceToImage();
@@ -505,6 +531,11 @@ void QVGPixmapData::ensureReadback(bool readOnly) const
             // because it may be shared (e.g. created via SgImage) and a subsequent
             // upload of the image data may produce unexpected results.
             const_cast<QVGPixmapData *>(this)->destroyImages();
+#if defined(Q_OS_SYMBIAN)
+            // There is now an own copy of the data so drop the handle provider,
+            // otherwise toVGImage() would request the handle again, which is wrong.
+            nativeImageHandleProvider = 0;
+#endif
             recreate = true;
         }
     }