Performance should always be better with cacheBuffer

Setting a cacheBuffer introduced more work for the scenegraph due to
cached delegates' visibility being toggled.  Changing visibility is
expensive as it is proagated to all children.  Introduce a cheap
method of hiding a branch instead.

Also avoid initiating incubation in the same frame as a completed
creation.

Change-Id: I573bcf37f441f96a7502d445be50ef4301f217d5
Reviewed-by: Bea Lam <bea.lam@nokia.com>

2 files changed, 8 insertions, 2 deletions

diff --git a/tests/auto/quick/shared/visualtestutil.cpp b/tests/auto/quick/shared/visualtestutil.cpp
index 8680df10e9..37d7323f8c 100644
--- a/tests/auto/quick/shared/visualtestutil.cpp
+++ b/tests/auto/quick/shared/visualtestutil.cpp
@@ -44,12 +44,17 @@
 #include <QtQuick/QQuickItem>
 #include <QtCore/QDebug>
 
+bool QQuickVisualTestUtil::delegateVisible(QQuickItem *item)
+{
+    return item->isVisible() && !QQuickItemPrivate::get(item)->culled;
+}
+
 QQuickItem *QQuickVisualTestUtil::findVisibleChild(QQuickItem *parent, const QString &objectName)
 {
     QQuickItem *item = 0;
     QList<QQuickItem*> items = parent->findChildren<QQuickItem*>(objectName);
     for (int i = 0; i < items.count(); ++i) {
-        if (items.at(i)->isVisible()) {
+        if (items.at(i)->isVisible() && !QQuickItemPrivate::get(items.at(i))->culled) {
             item = items.at(i);
             break;
         }
diff --git a/tests/auto/quick/shared/visualtestutil.h b/tests/auto/quick/shared/visualtestutil.h
index c2fc9cc01f..51f3f50b1f 100644
--- a/tests/auto/quick/shared/visualtestutil.h
+++ b/tests/auto/quick/shared/visualtestutil.h
@@ -53,6 +53,7 @@ namespace QQuickVisualTestUtil
 
     void dumpTree(QQuickItem *parent, int depth = 0);
 
+    bool delegateVisible(QQuickItem *item);
 
     /*
        Find an item with the specified objectName.  If index is supplied then the
@@ -90,7 +91,7 @@ namespace QQuickVisualTestUtil
         const QMetaObject &mo = T::staticMetaObject;
         for (int i = 0; i < parent->childItems().count(); ++i) {
             QQuickItem *item = qobject_cast<QQuickItem*>(parent->childItems().at(i));
-            if (!item || (visibleOnly && !item->isVisible()))
+            if (!item || (visibleOnly && (!item->isVisible() || QQuickItemPrivate::get(item)->culled)))
                 continue;
             if (mo.cast(item) && (objectName.isEmpty() || item->objectName() == objectName))
                 items.append(static_cast<T*>(item));