Introduce layerering support (ShaderEffectSource) directly in Item

This is enabled by doing "Item.layer.enabled: true". The implementation
is solely based on the existing shader effect (source) and simply
swaps in a sibling next to the item when enabled.

This change also adds the QSGTextureProvider to the public API,
as it is now a natural part of the QQuickItem API since all items
can be textures.

Change-Id: I26705c11e92d5623a5121300acc123782b784077
Reviewed-by: Kim M. Kalland <kim.kalland@nokia.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/src/quick/items/qquickitem.h b/src/quick/items/qquickitem.h
index 763fc59ac4..9810e0cf22 100644
--- a/src/quick/items/qquickitem.h
+++ b/src/quick/items/qquickitem.h
@@ -81,6 +81,7 @@ private:
     Q_DECLARE_PRIVATE(QQuickTransform)
 };
 
+class QQuickItemLayer;
 class QDeclarativeV8Function;
 class QDeclarativeState;
 class QQuickAnchorLine;
@@ -145,6 +146,8 @@ class Q_QUICK_EXPORT QQuickItem : public QObject, public QDeclarativeParserStatu
     Q_PROPERTY(qreal implicitWidth READ implicitWidth WRITE setImplicitWidth NOTIFY implicitWidthChanged)
     Q_PROPERTY(qreal implicitHeight READ implicitHeight WRITE setImplicitHeight NOTIFY implicitHeightChanged)
 
+    Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickItemLayer *layer READ layer DESIGNABLE false CONSTANT FINAL)
+
     Q_ENUMS(TransformOrigin)
     Q_CLASSINFO("DefaultProperty", "data")
     Q_CLASSINFO("qt_HasQmlAccessors", "true")
@@ -316,8 +319,8 @@ public:
        UpdatePaintNodeData();
     };
 
-    virtual bool isTextureProvider() const { return false; }
-    virtual QSGTextureProvider *textureProvider() const { return 0; }
+    virtual bool isTextureProvider() const;
+    virtual QSGTextureProvider *textureProvider() const;
 
 public Q_SLOTS:
     void update();