Make the OpenGL renderer a plugin

By default the QRenderAspect will try to load this plugin

Change-Id: Ie55e207fb8e6d0b64f717bbb99699eb669eaa3f2
Task-number: QTBUG-61151
Reviewed-by: Mike Krus <mike.krus@kdab.com>

6 files changed, 233 insertions, 5 deletions

diff --git a/src/render/texture/qtexture.cpp b/src/render/texture/qtexture.cpp
index 7f662dfc5..6b7b92166 100644
--- a/src/render/texture/qtexture.cpp
+++ b/src/render/texture/qtexture.cpp
@@ -57,7 +57,7 @@
 #include <Qt3DRender/private/managers_p.h>
 #include <Qt3DRender/private/texture_p.h>
 #include <Qt3DRender/private/qurlhelper_p.h>
-#include <Qt3DRender/private/glresourcemanagers_p.h>
+#include <qmath.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/render/texture/qtextureimagedata_p.h b/src/render/texture/qtextureimagedata_p.h
index d9a0952de..14095e2eb 100644
--- a/src/render/texture/qtextureimagedata_p.h
+++ b/src/render/texture/qtextureimagedata_p.h
@@ -52,12 +52,13 @@
 //
 
 #include "qtextureimagedata.h"
+#include <Qt3DRender/private/qt3drender_global_p.h>
 
 QT_BEGIN_NAMESPACE
 
 namespace Qt3DRender {
 
-class QTextureImageDataPrivate
+class Q_3DRENDERSHARED_PRIVATE_EXPORT QTextureImageDataPrivate
 {
 public:
     QTextureImageDataPrivate();
diff --git a/src/render/texture/texture.cpp b/src/render/texture/texture.cpp
index 795c5844e..dab037568 100644
--- a/src/render/texture/texture.cpp
+++ b/src/render/texture/texture.cpp
@@ -47,7 +47,7 @@
 #include <Qt3DCore/qpropertynoderemovedchange.h>
 
 #include <Qt3DRender/private/texture_p.h>
-#include <Qt3DRender/private/glresourcemanagers_p.h>
+#include <Qt3DRender/private/qabstracttexture_p.h>
 #include <Qt3DRender/private/managers_p.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/render/texture/texture_p.h b/src/render/texture/texture_p.h
index 83a05ebcc..61011bb68 100644
--- a/src/render/texture/texture_p.h
+++ b/src/render/texture/texture_p.h
@@ -128,7 +128,7 @@ struct TextureParameters
  *   Will query the TextureImplManager for an instance of TextureImpl that matches it's
  *   properties.
  */
-class Q_AUTOTEST_EXPORT Texture : public BackendNode
+class Q_3DRENDERSHARED_PRIVATE_EXPORT Texture : public BackendNode
 {
 public:
     Texture();
diff --git a/src/render/texture/texturedatamanager_p.h b/src/render/texture/texturedatamanager_p.h
new file mode 100644
index 000000000..61ebd1125
--- /dev/null
+++ b/src/render/texture/texturedatamanager_p.h
@@ -0,0 +1,227 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QT3DRENDER_RENDER_TEXTUREDATAMANAGER_H
+#define QT3DRENDER_RENDER_TEXTUREDATAMANAGER_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of other Qt classes.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QMutex>
+#include <QMutexLocker>
+#include <Qt3DRender/qtexture.h>
+#include <Qt3DRender/qtextureimagedata.h>
+#include <Qt3DRender/qtexturegenerator.h>
+#include <Qt3DRender/qtextureimagedatagenerator.h>
+#include <Qt3DRender/private/qt3drender_global_p.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace Qt3DRender {
+namespace Render {
+
+/**
+ * The texture data managers associates each texture data generator
+ * with the data objects generated by them. That is, either
+ *
+ *   QTextureImageDataGenerator -> QTextureImageData, or
+ *   QTextureGenerator -> QTextureData
+ *
+ * This way, texture classes only need to refer to the texture functors used.
+ * Aspect jobs will make sure that at the start of each frame, all generators
+ * registered with the GeneratorDataManagers have been executed.
+ *
+ * This guarantees that no texture data generator is executed twice.
+ *
+ * Each Generator is associated with a number of textures that reference it.
+ * If the last texture disassociates from a generator, the QTextureData will
+ * be deleted.
+ */
+template <class GeneratorPtr, class DataPtr, class ReferencedType>
+class GeneratorDataManager
+{
+public:
+    GeneratorDataManager() {}
+
+    /*!
+     * If no data for the given generator exists, make sure that the
+     * generators are executed the next frame. Reference generator by
+     * given texture
+     *
+     * Returns true if the Entry for a given generator had to be created
+     */
+    bool requestData(const GeneratorPtr &generator, ReferencedType r)
+    {
+        QMutexLocker lock(&m_mutex);
+
+        Entry *entry = findEntry(generator);
+        const bool needsToBeCreated = (entry == nullptr);
+        if (needsToBeCreated)
+            entry = createEntry(generator);
+        Q_ASSERT(entry);
+        if (!entry->referencingObjects.contains(r))
+            entry->referencingObjects.push_back(r);
+        return needsToBeCreated;
+    }
+
+    /*!
+     * Dereference given generator from texture. If no other textures still reference
+     * the generator, the associated data will be deleted
+     */
+    void releaseData(const GeneratorPtr &generator, ReferencedType r)
+    {
+        QMutexLocker lock(&m_mutex);
+
+        const auto end = m_data.end();
+        for (auto it = m_data.begin(); it != end; ++it) {
+            Entry &entry = *it;
+            if (*entry.generator == *generator) {
+                entry.referencingObjects.removeAll(r);
+                // delete, if that was the last reference
+                if (entry.referencingObjects.empty()) {
+                    m_data.erase(it);
+                    return;
+                }
+            }
+        }
+    }
+
+    /*!
+     * Return data associated with given generator, if existent
+     */
+    DataPtr getData(const GeneratorPtr &generator)
+    {
+        QMutexLocker lock(&m_mutex);
+
+        const Entry *entry = findEntry(generator);
+        return entry ? entry->data : DataPtr();
+    }
+
+    /*!
+     * Returns all generators that were not yet executed
+     */
+    QVector<GeneratorPtr> pendingGenerators()
+    {
+        QMutexLocker lock(&m_mutex);
+
+        QVector<GeneratorPtr> ret;
+        for (const Entry &entry : m_data)
+            if (!entry.data && !ret.contains(entry.generator))
+                ret.push_back(entry.generator);
+        return ret;
+    }
+
+    /*!
+     * Assigns a piece of data to the generator that was used to
+     * create it.
+     */
+    void assignData(const GeneratorPtr &generator, const DataPtr &data)
+    {
+        QMutexLocker lock(&m_mutex);
+
+        Entry *entry = findEntry(generator);
+        if (!entry) {
+            qWarning() << "[TextureDataManager] assignData() called with non-existent generator";
+            return;
+        }
+        entry->data = data;
+    }
+
+    bool contains(const GeneratorPtr &generator)
+    {
+        return findEntry(generator) != nullptr;
+    }
+
+private:
+
+    struct Entry {
+        GeneratorPtr generator;
+        QVector<ReferencedType> referencingObjects;
+        DataPtr data;
+    };
+
+    /*!
+     * Helper function: return entry for given generator if it exists, nullptr
+     * otherwise.
+     */
+    Entry* findEntry(const GeneratorPtr &generator)
+    {
+        for (int i = 0, sz = m_data.size(); i < sz; ++i)
+            if (*m_data[i].generator == *generator)
+                return &m_data[i];
+        return nullptr;
+    }
+
+    Entry *createEntry(const GeneratorPtr &generator)
+    {
+        Entry newEntry;
+        newEntry.generator = generator;
+
+        m_data.push_back(newEntry);
+        return &m_data.back();
+    }
+
+    QMutex m_mutex;
+    QVector<Entry> m_data;
+};
+
+class QT3DRENDERSHARED_PRIVATE_EXPORT TextureDataManager
+        : public GeneratorDataManager<QTextureGeneratorPtr, QTextureDataPtr, void*>
+{
+};
+
+class QT3DRENDERSHARED_PRIVATE_EXPORT TextureImageDataManager
+        : public GeneratorDataManager<QTextureImageDataGeneratorPtr, QTextureImageDataPtr, Qt3DCore::QNodeId>
+{
+};
+
+} // namespace Render
+} // namespace Qt3DRender
+
+QT_END_NAMESPACE
+
+#endif // TEXTUREDATAMANAGER_H
diff --git a/src/render/texture/textureimage_p.h b/src/render/texture/textureimage_p.h
index ced8f1ad2..42ef242a7 100644
--- a/src/render/texture/textureimage_p.h
+++ b/src/render/texture/textureimage_p.h
@@ -70,7 +70,7 @@ class TextureImageDataManager;
  * Backend class for QAbstractTextureImage.
  * Will only hold the generator and some info values.
  */
-class Q_AUTOTEST_EXPORT TextureImage : public BackendNode
+class Q_3DRENDERSHARED_PRIVATE_EXPORT TextureImage : public BackendNode
 {
 public:
     TextureImage();