Add possibility to mirror ShaderEffectSource generated textures

Using textures generated by ShaderEffectSource items (or Item.layer)
with custom OpenGL code was non-intuitive due to mismatching coordinate
systems, so added a possibility to control the generated texture
orientation.

[ChangeLog][QtQuick][ShaderEffectSource] Added possibility to mirror
generated OpenGL texture.

Change-Id: I7c03d8b6fbfc43d69812c15d244200fb8e7c7bb9
Reviewed-by: Gunnar Sletta <gunnar@sletta.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/quick/items/qquickshadereffectsource_p.h b/src/quick/items/qquickshadereffectsource_p.h
index 94bb315566..629acf0f55 100644
--- a/src/quick/items/qquickshadereffectsource_p.h
+++ b/src/quick/items/qquickshadereffectsource_p.h
@@ -66,6 +66,7 @@ class Q_QUICK_PRIVATE_EXPORT QQuickShaderEffectSource : public QQuickItem, publi
     Q_PROPERTY(bool hideSource READ hideSource WRITE setHideSource NOTIFY hideSourceChanged)
     Q_PROPERTY(bool mipmap READ mipmap WRITE setMipmap NOTIFY mipmapChanged)
     Q_PROPERTY(bool recursive READ recursive WRITE setRecursive NOTIFY recursiveChanged)
+    Q_PROPERTY(TextureMirroring textureMirroring READ textureMirroring WRITE setTextureMirroring NOTIFY textureMirroringChanged REVISION 1)
 
 public:
     enum WrapMode {
@@ -83,6 +84,13 @@ public:
     };
     Q_ENUM(Format)
 
+    enum TextureMirroring {
+        NoMirroring        = 0x00,
+        MirrorHorizontally = 0x01,
+        MirrorVertically   = 0x02
+    };
+    Q_ENUM(TextureMirroring)
+
     QQuickShaderEffectSource(QQuickItem *parent = 0);
     ~QQuickShaderEffectSource();
 
@@ -113,6 +121,9 @@ public:
     bool recursive() const;
     void setRecursive(bool enabled);
 
+    TextureMirroring textureMirroring() const;
+    void setTextureMirroring(TextureMirroring mirroring);
+
     bool isTextureProvider() const Q_DECL_OVERRIDE { return true; }
     QSGTextureProvider *textureProvider() const Q_DECL_OVERRIDE;
 
@@ -128,6 +139,7 @@ Q_SIGNALS:
     void hideSourceChanged();
     void mipmapChanged();
     void recursiveChanged();
+    void textureMirroringChanged();
 
     void scheduledUpdateCompleted();
 
@@ -157,6 +169,7 @@ private:
     uint m_mipmap : 1;
     uint m_recursive : 1;
     uint m_grab : 1;
+    uint m_textureMirroring : 2; // Stores TextureMirroring enum
 };
 
 QT_END_NAMESPACE