direct2d: Fix composition mode support

When the composition mode changes to a mode which is not supported by
Direct2D's primitive blending, the rendering follows the emulated (slow)
code path using rasterFill(). This allows the direct2d paint engine to
handle all composition modes supported by QImage.

Task-number: QTBUG-40602
Change-Id: I0ac0b5c89aab2483cb2ef7768d6dec8e16913249
Done-with: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Andrew Knight <andrew.knight@digia.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/plugins/platforms/direct2d/qwindowsdirect2ddevicecontext.h b/src/plugins/platforms/direct2d/qwindowsdirect2ddevicecontext.h
index b46b850305..458f8a2598 100644
--- a/src/plugins/platforms/direct2d/qwindowsdirect2ddevicecontext.h
+++ b/src/plugins/platforms/direct2d/qwindowsdirect2ddevicecontext.h
@@ -69,6 +69,7 @@ class QWindowsDirect2DDeviceContextPrivate;
 class QWindowsDirect2DDeviceContext
 {
     Q_DECLARE_PRIVATE(QWindowsDirect2DDeviceContext)
+    friend class QWindowsDirect2DDeviceContextSuspender;
 public:
     QWindowsDirect2DDeviceContext(ID2D1DeviceContext *dc);
     ~QWindowsDirect2DDeviceContext();
@@ -79,9 +80,23 @@ public:
     bool end();
 
 private:
+    void suspend();
+    void resume();
+
     QScopedPointer<QWindowsDirect2DDeviceContextPrivate> d_ptr;
 };
 
+class QWindowsDirect2DDeviceContextSuspender {
+    Q_DISABLE_COPY(QWindowsDirect2DDeviceContextSuspender)
+
+    QWindowsDirect2DDeviceContext *m_dc;
+public:
+    QWindowsDirect2DDeviceContextSuspender(QWindowsDirect2DDeviceContext *dc);
+    ~QWindowsDirect2DDeviceContextSuspender();
+
+    void resume();
+};
+
 QT_END_NAMESPACE
 
 #endif // QWINDOWSDIRECT2DDEVICECONTEXT_H