1 files changed, 113 insertions, 0 deletions
diff --git a/src/render/backend/entityvisitor.cpp b/src/render/backend/entityvisitor.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2019 Klaralvdalens Datakonsult AB (KDAB).
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt3D module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "entityvisitor_p.h"
+#include <Qt3DRender/private/managers_p.h>
+#include <Qt3DRender/private/nodemanagers_p.h>
+
+QT_USE_NAMESPACE
+using namespace Qt3DRender::Render;
+
+EntityVisitor::EntityVisitor(NodeManagers *manager)
+    : m_manager(manager)
+    , m_pruneDisabled(false)
+{
+
+}
+
+EntityVisitor::~EntityVisitor() = default;
+
+/*!
+ * \internal
+ *
+ * Override in derived class to do work on the current entity
+ *
+ * Return value (Continue, Prune, Stop) will affect traversal
+ */
+EntityVisitor::Operation EntityVisitor::visit(Entity *entity) {
+    // return false to stop traversal
+    if (!entity)
+        return Stop;
+    return Continue;
+}
+
+/*!
+ * \internal
+ *
+ * If true, disabled entities and all their children will be ignored
+ * during traversal
+ *
+ */
+bool EntityVisitor::pruneDisabled() const
+{
+    return m_pruneDisabled;
+}
+
+void EntityVisitor::setPruneDisabled(bool pruneDisabled)
+{
+    m_pruneDisabled = pruneDisabled;
+}
+
+/*!
+ * \internal
+ *
+ * Call on the root of the tree that should be traversed.
+ * Returns false if any visit resulted in Stop
+ */
+bool EntityVisitor::apply(Entity *root) {
+    if (!root)
+        return false;
+    if (m_pruneDisabled && !root->isEnabled())
+        return true;
+
+    const auto op = visit(root);
+    if (op == Stop)
+        return false;
+    if (op == Prune)
+        return true;
+
+    const auto childrenHandles = root->childrenHandles();
+    for (const HEntity &handle : childrenHandles) {
+        Entity *child = m_manager->renderNodesManager()->data(handle);
+        if (child != nullptr && !apply(child))
+            return false;
+    }
+
+    return true;
+}