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, 18 insertions, 8 deletions

diff --git a/src/quick/items/qquickopenglshadereffect_p.h b/src/quick/items/qquickopenglshadereffect_p.h
index 062eedd744..44b60c97d9 100644
--- a/src/quick/items/qquickopenglshadereffect_p.h
+++ b/src/quick/items/qquickopenglshadereffect_p.h
@@ -61,6 +61,7 @@
 #include "qquickshadereffectmesh_p.h"
 
 #include <QtCore/qpointer.h>
+#include <functional>
 
 QT_BEGIN_NAMESPACE
 
@@ -69,32 +70,39 @@ class QSignalMapper;
 class QFileSelector;
 class QQuickOpenGLCustomMaterialShader;
 
+namespace QtPrivate {
+class MappedSlotObject;
+}
+
 // Common class for QQuickOpenGLShaderEffect and QQuickCustomParticle.
 struct Q_QUICK_PRIVATE_EXPORT QQuickOpenGLShaderEffectCommon
 {
     typedef QQuickOpenGLShaderEffectMaterialKey Key;
     typedef QQuickOpenGLShaderEffectMaterial::UniformData UniformData;
 
-    QQuickOpenGLShaderEffectCommon(QObject *host) : host(host), fileSelector(nullptr) { }
-    ~QQuickOpenGLShaderEffectCommon();
+    QQuickOpenGLShaderEffectCommon(QObject *host, std::function<void(int)> mappedPropertyChanged)
+        : host(host), mappedPropertyChanged(mappedPropertyChanged), fileSelector(nullptr)
+    { }
+
     void disconnectPropertySignals(QQuickItem *item, Key::ShaderType shaderType);
-    void connectPropertySignals(QQuickItem *item, Key::ShaderType shaderType);
+    void connectPropertySignals(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType);
     void updateParseLog(bool ignoreAttributes);
-    void lookThroughShaderCode(QQuickItem *item, Key::ShaderType shaderType, const QByteArray &code);
-    void updateShader(QQuickItem *item, Key::ShaderType shaderType);
+    void lookThroughShaderCode(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType, const QByteArray &code);
+    void updateShader(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType);
     void updateMaterial(QQuickOpenGLShaderEffectNode *node, QQuickOpenGLShaderEffectMaterial *material,
                         bool updateUniforms, bool updateUniformValues, bool updateTextureProviders);
     void updateWindow(QQuickWindow *window);
 
     // Called by slots in QQuickOpenGLShaderEffect:
     void sourceDestroyed(QObject *object);
-    void propertyChanged(QQuickItem *item, int mappedId, bool *textureProviderChanged);
+    void propertyChanged(QQuickItem *item, const QMetaObject *itemMetaObject, int mappedId, bool *textureProviderChanged);
 
     QObject *host;
+    std::function<void(int)> mappedPropertyChanged;
     Key source;
     QVector<QByteArray> attributes;
     QVector<UniformData> uniformData[Key::ShaderTypeCount];
-    QVector<QSignalMapper *> signalMappers[Key::ShaderTypeCount];
+    QVector<QtPrivate::MappedSlotObject *> signalMappers[Key::ShaderTypeCount];
     QString parseLog;
     QFileSelector *fileSelector;
 };
@@ -142,9 +150,10 @@ private Q_SLOTS:
     void updateGeometryIfAtlased();
     void updateLogAndStatus(const QString &log, int status);
     void sourceDestroyed(QObject *object);
-    void propertyChanged(int mappedId);
 
 private:
+    void propertyChanged(int mappedId);
+
     friend class QQuickCustomMaterialShader;
     friend class QQuickOpenGLShaderEffectNode;
 
@@ -152,6 +161,7 @@ private:
     typedef QQuickOpenGLShaderEffectMaterial::UniformData UniformData;
 
     QQuickShaderEffect *m_item;
+    const QMetaObject *m_itemMetaObject;
     QSize m_meshResolution;
     QQuickShaderEffectMesh *m_mesh;
     QQuickGridMesh m_defaultMesh;