Add QQuickWindow::TextureIsOpaque as option to createTextureFromImage.

Opaque textures can be a lot faster, so give this option without
forcing the user to reimplement her/his own QSGTexture class.

The old behavior was that createTextureFromImage() disregarded
TextureHasAlphaChannel and looked solely at the image's format. To
keep this behavior intact, we introduce a second opt-in flag to switch
textures from auto-detect to false, namely TextureIsOpaque.

[ChangeLog][QtQuick][QQuickWindow] Add TextureIsOpaque option to
createTextureFromImage()

Change-Id: I248db4bc5f7920864b6aa8d831ce24d23ad370ef
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/tests/auto/quick/scenegraph/tst_scenegraph.cpp b/tests/auto/quick/scenegraph/tst_scenegraph.cpp
index 3e1285b7fe..80672e234e 100644
--- a/tests/auto/quick/scenegraph/tst_scenegraph.cpp
+++ b/tests/auto/quick/scenegraph/tst_scenegraph.cpp
@@ -104,6 +104,9 @@ private slots:
 
     void hideWithOtherContext();
 
+    void createTextureFromImage_data();
+    void createTextureFromImage();
+
 private:
     bool m_brokenMipmapSupport;
 };
@@ -534,6 +537,34 @@ void tst_SceneGraph::hideWithOtherContext()
     QVERIFY(!renderingOnMainThread || QOpenGLContext::currentContext() != &context);
 }
 
+void tst_SceneGraph::createTextureFromImage_data()
+{
+    QImage rgba(64, 64, QImage::Format_ARGB32_Premultiplied);
+    QImage rgb(64, 64, QImage::Format_RGB32);
+
+    QTest::addColumn<QImage>("image");
+    QTest::addColumn<uint>("flags");
+    QTest::addColumn<bool>("expectedAlpha");
+
+    QTest::newRow("rgb") << rgb << uint(0) << false;
+    QTest::newRow("argb") << rgba << uint(0) << true;
+    QTest::newRow("rgb,alpha") << rgb << uint(QQuickWindow::TextureHasAlphaChannel) << false;
+    QTest::newRow("argb,alpha") << rgba << uint(QQuickWindow::TextureHasAlphaChannel) << true;
+    QTest::newRow("rgb,!alpha") << rgb << uint(QQuickWindow::TextureIsOpaque) << false;
+    QTest::newRow("argb,!alpha") << rgba << uint(QQuickWindow::TextureIsOpaque) << false;
+}
+
+void tst_SceneGraph::createTextureFromImage()
+{
+    QFETCH(QImage, image);
+    QFETCH(uint, flags);
+    QFETCH(bool, expectedAlpha);
+
+    QQuickView view;
+    QScopedPointer<QSGTexture> texture(view.createTextureFromImage(image, (QQuickWindow::CreateTextureOptions) flags));
+    QCOMPARE(texture->hasAlphaChannel(), expectedAlpha);
+}
+
 
 #include "tst_scenegraph.moc"