Use RGB64 qdrawhelper routines for unpremultiplied formats

The ARGB32PM code-path doesn't have enough precision to accurately
render ARGB32 images, but the RGB64 code-path does. Since this is
already a slow configuration and the most costly part is the conversion
we can switch to the more accurate code-path for little cost.

Task-number: QTBUG-55720
Change-Id: Ifa0afba8d8cc0c2f699bb91f51726f4ee5228f3e
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>

1 files changed, 13 insertions, 0 deletions

diff --git a/tests/auto/other/lancelot/tst_lancelot.cpp b/tests/auto/other/lancelot/tst_lancelot.cpp
index 8fc0521102..972e5ca967 100644
--- a/tests/auto/other/lancelot/tst_lancelot.cpp
+++ b/tests/auto/other/lancelot/tst_lancelot.cpp
@@ -69,6 +69,8 @@ private slots:
     void testRasterARGB32PM();
     void testRasterRGB32_data();
     void testRasterRGB32();
+    void testRasterARGB32_data();
+    void testRasterARGB32();
     void testRasterRGB16_data();
     void testRasterRGB16();
     void testRasterA2RGB30PM_data();
@@ -134,6 +136,17 @@ void tst_Lancelot::testRasterARGB32PM()
 }
 
 
+void tst_Lancelot::testRasterARGB32_data()
+{
+    setupTestSuite();
+}
+
+void tst_Lancelot::testRasterARGB32()
+{
+    runTestSuite(Raster, QImage::Format_ARGB32);
+}
+
+
 void tst_Lancelot::testRasterRGB32_data()
 {
     setupTestSuite();