QtQuick: clean up shader effect property connections

- Don't use a signal mapper, but handle the mapping using a custom slot
  object and a lambda to do the dispatching ourselves.
- Don't do meta-calls by property name, but by index.
- Cache the meta-object.
- Resolve the property indices by using the QML property cache.

For a shader with 6 property connections, the time spent goes from 320k
instructions to 80k instructions (valgrind on x86_64).

Task-number: QTBUG-53901
Change-Id: I2809198cf62f9716b3683798222203fc3e97fbb3
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/quick/items/qquickopenglshadereffectnode_p.h b/src/quick/items/qquickopenglshadereffectnode_p.h
index adf5ef730b..5abe3ae3d0 100644
--- a/src/quick/items/qquickopenglshadereffectnode_p.h
+++ b/src/quick/items/qquickopenglshadereffectnode_p.h
@@ -90,9 +90,19 @@ public:
 
         QByteArray name;
         QVariant value;
+        int propertyIndex = -1;
         SpecialType specialType;
 
         bool operator == (const UniformData &other) const;
+
+        void setValueFromProperty(QObject *item, const QMetaObject *itemMetaObject)
+        {
+            if (propertyIndex == -1) {
+                value = item->property(name);
+            } else {
+                value = itemMetaObject->property(propertyIndex).read(item);
+            }
+        }
     };
 
     explicit QQuickOpenGLShaderEffectMaterial(QQuickOpenGLShaderEffectNode *node = 0);