Add flamegraph view

Change-Id: I001053b63d27adcbbdfd95abb2b45f5f5fa05447
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>

plugins/qmlprofiler/flamegraph.cpp

@@ -0,0 +1,175 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd
+** All rights reserved.
+** For any questions to The Qt Company, please use contact form at http://www.qt.io/contact-us
+**
+** This file is part of the Qt Enterprise Qt Quick Profiler Add-on.
+**
+** Licensees holding valid Qt Enterprise licenses may use this file in
+** accordance with the Qt Enterprise License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://www.qt.io/contact-us
+**
+****************************************************************************/
+
+#include "flamegraph.h"
+
+namespace QmlProfilerExtension {
+namespace Internal {
+
+FlameGraph::FlameGraph(QQuickItem *parent) :
+    QQuickItem(parent), m_delegate(0), m_model(0), m_depth(0), m_sizeThreshold(0)
+{
+}
+
+QQmlComponent *FlameGraph::delegate() const
+{
+    return m_delegate;
+}
+
+void FlameGraph::setDelegate(QQmlComponent *delegate)
+{
+    if (delegate != m_delegate) {
+        m_delegate = delegate;
+        emit delegateChanged(delegate);
+    }
+}
+
+QAbstractItemModel *FlameGraph::model() const
+{
+    return m_model;
+}
+
+void FlameGraph::setModel(QAbstractItemModel *model)
+{
+    if (model != m_model) {
+        if (m_model)
+            disconnect(m_model, &QAbstractItemModel::modelReset, this, &FlameGraph::rebuild);
+
+        m_model = model;
+        connect(m_model, &QAbstractItemModel::modelReset, this, &FlameGraph::rebuild);
+        emit modelChanged(model);
+        rebuild();
+    }
+}
+
+int FlameGraph::sizeRole() const
+{
+    return m_sizeRole;
+}
+
+void FlameGraph::setSizeRole(int sizeRole)
+{
+    if (sizeRole != m_sizeRole) {
+        m_sizeRole = sizeRole;
+        emit sizeRoleChanged(sizeRole);
+        rebuild();
+    }
+}
+
+qreal FlameGraph::sizeThreshold() const
+{
+    return m_sizeThreshold;
+}
+
+void FlameGraph::setSizeThreshold(qreal sizeThreshold)
+{
+    if (sizeThreshold != m_sizeThreshold) {
+        m_sizeThreshold = sizeThreshold;
+        emit sizeThresholdChanged(sizeThreshold);
+        rebuild();
+    }
+}
+
+int FlameGraph::depth() const
+{
+    return m_depth;
+}
+
+FlameGraphAttached *FlameGraph::qmlAttachedProperties(QObject *object)
+{
+    FlameGraphAttached *attached =
+            object->findChild<FlameGraphAttached *>(QString(), Qt::FindDirectChildrenOnly);
+    if (!attached)
+        attached = new FlameGraphAttached(object);
+    return attached;
+}
+
+QObject *FlameGraph::appendChild(QObject *parentObject, QQuickItem *parentItem,
+                                 QQmlContext *context, const QModelIndex &childIndex,
+                                 qreal position, qreal size)
+{
+    QObject *childObject = m_delegate->beginCreate(context);
+    if (parentItem) {
+        QQuickItem *childItem = qobject_cast<QQuickItem *>(childObject);
+        if (childItem)
+            childItem->setParentItem(parentItem);
+    }
+    childObject->setParent(parentObject);
+    FlameGraphAttached *attached = FlameGraph::qmlAttachedProperties(childObject);
+    attached->setRelativePosition(position);
+    attached->setRelativeSize(size);
+    attached->setModelIndex(childIndex);
+    m_delegate->completeCreate();
+    return childObject;
+}
+
+
+int FlameGraph::buildNode(const QModelIndex &parentIndex, QObject *parentObject, int depth)
+{
+    qreal position = 0;
+    qreal skipped = 0;
+    qreal parentSize = m_model->data(parentIndex, m_sizeRole).toReal();
+    QQuickItem *parentItem = qobject_cast<QQuickItem *>(parentObject);
+    QQmlContext *context = qmlContext(this);
+    int rowCount = m_model->rowCount(parentIndex);
+    int childrenDepth = depth;
+    for (int row = 0; row < rowCount; ++row) {
+        QModelIndex childIndex = m_model->index(row, 0, parentIndex);
+        qreal size = m_model->data(childIndex, m_sizeRole).toReal();
+        if (size / m_model->data(QModelIndex(), m_sizeRole).toReal() < m_sizeThreshold) {
+            skipped += size;
+            continue;
+        }
+
+        QObject *childObject = appendChild(parentObject, parentItem, context, childIndex,
+                                           position / parentSize, size / parentSize);
+        position += size;
+        childrenDepth = qMax(childrenDepth, buildNode(childIndex, childObject, depth + 1));
+    }
+
+    if (skipped > 0) {
+        appendChild(parentObject, parentItem, context, QModelIndex(), position / parentSize,
+                    skipped / parentSize);
+        childrenDepth = qMax(childrenDepth, depth + 1);
+    }
+
+    return childrenDepth;
+}
+
+void FlameGraph::rebuild()
+{
+    qDeleteAll(childItems());
+    childItems().clear();
+    m_depth = 0;
+
+    if (!m_model) {
+        emit depthChanged(m_depth);
+        return;
+    }
+
+    m_depth = buildNode(QModelIndex(), this, 0);
+    emit depthChanged(m_depth);
+}
+
+QVariant FlameGraphAttached::data(int role) const
+{
+    return m_data.isValid() ? m_data.data(role) : QVariant();
+}
+
+}
+}