Introduce state storing for mac and android.

At least some mac and android environments do not handle
shared contexts properly, leading to slowdowns and/or artifacts.
Disable context sharing on mac and android, and instead
store and restore relevant opengl state.

Also improve renderer and context cleanup

Change-Id: I8fa596b95f6ff20d53c950a34b5c28513acbc18f
Reviewed-by: Tomi Korpipää <tomi.korpipaa@digia.com>

10 files changed, 1033 insertions, 24 deletions

diff --git a/src/datavisualization/engine/abstract3dcontroller.cpp b/src/datavisualization/engine/abstract3dcontroller.cpp
index d2b59c58..acb63f0a 100644
--- a/src/datavisualization/engine/abstract3dcontroller.cpp
+++ b/src/datavisualization/engine/abstract3dcontroller.cpp
@@ -81,13 +81,19 @@ Abstract3DController::Abstract3DController(QRect initialViewport, Q3DScene *scen
 
 Abstract3DController::~Abstract3DController()
 {
+    destroyRenderer();
+    delete m_scene;
+    delete m_themeManager;
+}
+
+void Abstract3DController::destroyRenderer()
+{
     // Renderer can be in another thread, don't delete it directly in that case
     if (m_renderer && m_renderer->thread() != QThread::currentThread())
         m_renderer->deleteLater();
     else
         delete m_renderer;
-    delete m_scene;
-    delete m_themeManager;
+    m_renderer = 0;
 }
 
 /**
diff --git a/src/datavisualization/engine/abstract3dcontroller_p.h b/src/datavisualization/engine/abstract3dcontroller_p.h
index f9b6588d..5bae17d6 100644
--- a/src/datavisualization/engine/abstract3dcontroller_p.h
+++ b/src/datavisualization/engine/abstract3dcontroller_p.h
@@ -161,6 +161,7 @@ public:
     virtual ~Abstract3DController();
 
     inline bool isInitialized() { return (m_renderer != 0); }
+    virtual void destroyRenderer();
     virtual void synchDataToRenderer();
     virtual void render(const GLuint defaultFboHandle = 0);
     virtual void initializeOpenGL() = 0;
diff --git a/src/datavisualization/engine/qabstract3dgraph.cpp b/src/datavisualization/engine/qabstract3dgraph.cpp
index 1551c639..cce2c235 100644
--- a/src/datavisualization/engine/qabstract3dgraph.cpp
+++ b/src/datavisualization/engine/qabstract3dgraph.cpp
@@ -450,6 +450,9 @@ QAbstract3DGraphPrivate::QAbstract3DGraphPrivate(QAbstract3DGraph *q)
 
 QAbstract3DGraphPrivate::~QAbstract3DGraphPrivate()
 {
+    if (m_context)
+        m_context->makeCurrent(q_ptr);
+
     delete m_visualController;
 }
 
diff --git a/src/datavisualizationqml2/abstractdeclarative.cpp b/src/datavisualizationqml2/abstractdeclarative.cpp
index ce74d541..e7a5c7eb 100644
--- a/src/datavisualizationqml2/abstractdeclarative.cpp
+++ b/src/datavisualizationqml2/abstractdeclarative.cpp
@@ -21,7 +21,6 @@
 #include "declarativetheme_p.h"
 #include "declarativerendernode_p.h"
 
-#include <QtCore/QThread>
 #include <QtGui/QGuiApplication>
 
 QT_BEGIN_NAMESPACE_DATAVISUALIZATION
@@ -33,8 +32,6 @@ static QHash<QQuickWindow *, bool> windowClearList;
 AbstractDeclarative::AbstractDeclarative(QQuickItem *parent) :
     QQuickItem(parent),
     m_controller(0),
-    m_context(0),
-    m_qtContext(0),
     m_contextWindow(0),
     m_renderMode(RenderIndirect),
 #if defined(QT_OPENGL_ES_2)
@@ -43,7 +40,15 @@ AbstractDeclarative::AbstractDeclarative(QQuickItem *parent) :
     m_samples(4),
 #endif
     m_windowSamples(0),
-    m_initialisedSize(0, 0)
+    m_initialisedSize(0, 0),
+#ifdef USE_SHARED_CONTEXT
+    m_context(0),
+#else
+    m_stateStore(0),
+#endif
+    m_qtContext(0),
+    m_mainThread(QThread::currentThread()),
+    m_contextThread(0)
 {
     connect(this, &QQuickItem::windowChanged, this, &AbstractDeclarative::handleWindowChanged);
     setAntialiasing(m_samples > 0);
@@ -54,12 +59,23 @@ AbstractDeclarative::AbstractDeclarative(QQuickItem *parent) :
 
 AbstractDeclarative::~AbstractDeclarative()
 {
-#if !defined(Q_OS_MAC)
+#ifdef USE_SHARED_CONTEXT
     // Context can be in another thread, don't delete it directly in that case
-    if (m_context && m_context->thread() != QThread::currentThread())
-        m_context->deleteLater();
-    else
+    if (m_contextThread && m_contextThread != m_mainThread) {
+        if (m_context)
+            m_context->deleteLater();
+        m_context = 0;
+    } else {
         delete m_context;
+    }
+#else
+    if (m_contextThread && m_contextThread != m_mainThread) {
+        if (m_stateStore)
+            m_stateStore->deleteLater();
+        m_stateStore = 0;
+    } else {
+        delete m_stateStore;
+    }
 #endif
 
     disconnect(this, 0, this, 0);
@@ -216,28 +232,75 @@ void AbstractDeclarative::setSharedController(Abstract3DController *controller)
 
 void AbstractDeclarative::activateOpenGLContext(QQuickWindow *window)
 {
-#if !defined(Q_OS_MAC)
-    if (!m_context || m_contextWindow != window) {
-        m_contextWindow = window;
+#ifdef USE_SHARED_CONTEXT
+    // We can assume we are not in middle of AbstractDeclarative destructor when we are here,
+    // since m_context creation is always done when this function is called from
+    // synchDataToRenderer(), which blocks main thread -> no need to mutex.
+    if (!m_context || !m_qtContext || m_contextWindow != window) {
+        QOpenGLContext *currentContext = QOpenGLContext::currentContext();
+
+        if (m_context && currentContext != m_qtContext) {
+            // If Qt context has changed, the old renderer needs to go.
+            // If the old context window no longer exists, it is okay to delete renderer
+            // in null context, as we can assume Qt context for the window is also gone.
+            m_context->makeCurrent(m_contextWindow);
+            m_controller->destroyRenderer();
+            m_context->doneCurrent(); // So that we don't delete active context
+        }
+
         delete m_context;
-        m_qtContext = QOpenGLContext::currentContext();
+
+        m_contextThread = QThread::currentThread();
+        m_contextWindow = window;
+        m_qtContext = currentContext;
+
         m_context = new QOpenGLContext();
-        m_context->setFormat(window->requestedFormat());
+        m_context->setFormat(m_qtContext->format());
         m_context->setShareContext(m_qtContext);
         m_context->create();
+
+        m_context->makeCurrent(window);
+        m_controller->initializeOpenGL();
+    } else {
+        m_context->makeCurrent(window);
     }
-    m_context->makeCurrent(window);
 #else
-    Q_UNUSED(window)
+    // Shared contexts don't work properly in some platforms, so just store the
+    // context state on those
+    if (!m_stateStore || !m_qtContext || m_contextWindow != window) {
+        QOpenGLContext *currentContext = QOpenGLContext::currentContext();
+
+        if (m_qtContext && currentContext != m_qtContext) {
+            // If Qt context has changed but still exists, the old renderer needs to go.
+            // If the old context window no longer exists, it is okay to delete renderer
+            // in null context (though it is likely Qt context is gone in that case, too.)
+            m_qtContext->makeCurrent(m_contextWindow);
+            m_controller->destroyRenderer();
+            currentContext->makeCurrent(window);
+        }
+
+        m_contextThread = QThread::currentThread();
+        m_contextWindow = window;
+        m_qtContext = currentContext;
+
+        delete m_stateStore;
+        m_stateStore = new GLStateStore(QOpenGLContext::currentContext());
+
+        m_stateStore->storeGLState();
+        m_controller->initializeOpenGL();
+    } else {
+        m_stateStore->storeGLState();
+    }
 #endif
 }
 
 void AbstractDeclarative::doneOpenGLContext(QQuickWindow *window)
 {
-#if !defined(Q_OS_MAC)
+#ifdef USE_SHARED_CONTEXT
     m_qtContext->makeCurrent(window);
 #else
     Q_UNUSED(window)
+    m_stateStore->restoreGLState();
 #endif
 }
 
@@ -248,7 +311,6 @@ void AbstractDeclarative::synchDataToRenderer()
 
     QQuickWindow *win = window();
     activateOpenGLContext(win);
-    m_controller->initializeOpenGL();
     m_controller->synchDataToRenderer();
     doneOpenGLContext(win);
 }
diff --git a/src/datavisualizationqml2/abstractdeclarative_p.h b/src/datavisualizationqml2/abstractdeclarative_p.h
index d44a154d..ac8bf9be 100644
--- a/src/datavisualizationqml2/abstractdeclarative_p.h
+++ b/src/datavisualizationqml2/abstractdeclarative_p.h
@@ -29,15 +29,24 @@
 #ifndef ABSTRACTDECLARATIVE_P_H
 #define ABSTRACTDECLARATIVE_P_H
 
+#if !defined(Q_OS_MAC) && !defined(Q_OS_ANDROID)
+#define USE_SHARED_CONTEXT
+#endif
+
 #include "datavisualizationglobal_p.h"
 #include "abstract3dcontroller_p.h"
 #include "qabstract3dinputhandler.h"
 #include "declarativescene_p.h"
 
+#ifndef USE_SHARED_CONTEXT
+#include "glstatestore_p.h"
+#endif
+
 #include <QtCore/QAbstractItemModel>
 #include <QtQuick/QQuickItem>
 #include <QtQuick/QQuickWindow>
 #include <QtCore/QPointer>
+#include <QtCore/QThread>
 
 QT_BEGIN_NAMESPACE_DATAVISUALIZATION
 
@@ -158,13 +167,19 @@ signals:
 private:
     QPointer<Abstract3DController> m_controller;
     QRectF m_cachedGeometry;
-    QOpenGLContext *m_context;
-    QOpenGLContext *m_qtContext;
-    QQuickWindow *m_contextWindow;
+    QPointer<QQuickWindow> m_contextWindow;
     AbstractDeclarative::RenderingMode m_renderMode;
     int m_samples;
     int m_windowSamples;
     QSize m_initialisedSize;
+#ifdef USE_SHARED_CONTEXT
+    QOpenGLContext *m_context;
+#else
+    GLStateStore *m_stateStore;
+#endif
+    QPointer<QOpenGLContext> m_qtContext;
+    QThread *m_mainThread;
+    QThread *m_contextThread;
 };
 Q_DECLARE_OPERATORS_FOR_FLAGS(AbstractDeclarative::SelectionFlags)
 
diff --git a/src/datavisualizationqml2/datavisualizationqml2.pro b/src/datavisualizationqml2/datavisualizationqml2.pro
index df6c647d..ed91b111 100644
--- a/src/datavisualizationqml2/datavisualizationqml2.pro
+++ b/src/datavisualizationqml2/datavisualizationqml2.pro
@@ -26,7 +26,9 @@ SOURCES += \
     declarativetheme.cpp \
     declarativecolor.cpp \
     declarativescene.cpp \
-    declarativerendernode.cpp
+    declarativerendernode.cpp \
+    glstatestore.cpp \
+    enumtostringmap.cpp
 
 HEADERS += \
     datavisualizationqml2_plugin.h \
@@ -39,7 +41,9 @@ HEADERS += \
     declarativetheme_p.h \
     declarativecolor_p.h \
     declarativescene_p.h \
-    declarativerendernode_p.h
+    declarativerendernode_p.h \
+    glstatestore_p.h \
+    enumtostringmap_p.h
 
 OTHER_FILES = qmldir
 
diff --git a/src/datavisualizationqml2/enumtostringmap.cpp b/src/datavisualizationqml2/enumtostringmap.cpp
new file mode 100644
index 00000000..fd68c6bb
--- /dev/null
+++ b/src/datavisualizationqml2/enumtostringmap.cpp
@@ -0,0 +1,393 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc
+** All rights reserved.
+** For any questions to Digia, please use contact form at http://qt.digia.com
+**
+** This file is part of the QtDataVisualization module.
+**
+** 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 Digia.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://qt.digia.com
+**
+****************************************************************************/
+#include "enumtostringmap_p.h"
+#include <QString>
+#include <QDebug>
+
+static EnumToStringMap *theInstance = 0;
+static unsigned int theInstanceCount = 0;
+
+EnumToStringMap *EnumToStringMap::newInstance()
+{
+    if (theInstance) {
+        theInstanceCount++;
+        return theInstance;
+    }
+
+    theInstance = new EnumToStringMap();
+    theInstanceCount++;
+    return theInstance;
+}
+
+void EnumToStringMap::deleteInstance()
+{
+    theInstanceCount--;
+    if (theInstanceCount <= 0) {
+        delete theInstance;
+        theInstance = 0;
+    }
+}
+
+EnumToStringMap::EnumToStringMap() :
+    m_unknown("<unknown>")
+{
+    m_map[GL_ZERO] = "ZERO/null";
+
+    m_map[GL_DEPTH_BUFFER_BIT] = "DEPTH_BUFFER_BIT";
+    m_map[GL_STENCIL_BUFFER_BIT] = "STENCIL_BUFFER_BIT";
+    m_map[GL_COLOR_BUFFER_BIT] = "COLOR_BUFFER_BIT";
+
+    m_map[GL_STENCIL_BUFFER_BIT] = "STENCIL_BUFFER_BIT";
+    m_map[GL_COLOR_BUFFER_BIT] = "COLOR_BUFFER_BIT";
+
+    m_map[GL_POINTS] = "POINTS";
+    m_map[GL_LINES] = "LINES";
+    m_map[GL_LINE_LOOP] = "LINE_LOOP";
+    m_map[GL_LINE_STRIP] = "LINE_STRIP";
+    m_map[GL_TRIANGLES] = "TRIANGLES";
+    m_map[GL_TRIANGLE_STRIP] = "TRIANGLE_STRIP";
+    m_map[GL_TRIANGLE_FAN] = "TRIANGLE_FAN";
+
+    m_map[GL_SRC_COLOR] = "SRC_COLOR";
+    m_map[GL_ONE_MINUS_SRC_COLOR] = "ONE_MINUS_SRC_COLOR";
+    m_map[GL_SRC_ALPHA] = "SRC_ALPHA";
+    m_map[GL_ONE_MINUS_SRC_ALPHA] = "ONE_MINUS_SRC_ALPHA";
+    m_map[GL_DST_ALPHA] = "DST_ALPHA";
+    m_map[GL_ONE_MINUS_DST_ALPHA] = "ONE_MINUS_DST_ALPHA";
+
+    m_map[GL_DST_COLOR] = "DST_COLOR";
+    m_map[GL_ONE_MINUS_DST_COLOR] = "ONE_MINUS_DST_COLOR";
+    m_map[GL_SRC_ALPHA_SATURATE] = "SRC_ALPHA_SATURATE";
+
+    m_map[GL_FUNC_ADD] = "FUNC_ADD";
+    m_map[GL_BLEND_EQUATION] = "BLEND_EQUATION";
+    m_map[GL_BLEND_EQUATION_RGB] = "BLEND_EQUATION_RGB";
+    m_map[GL_BLEND_EQUATION_ALPHA] = "BLEND_EQUATION_ALPHA";
+
+    m_map[GL_FUNC_SUBTRACT] = "FUNC_SUBTRACT";
+    m_map[GL_FUNC_REVERSE_SUBTRACT] = "FUNC_REVERSE_SUBTRACT";
+
+    m_map[GL_BLEND_DST_RGB] = "BLEND_DST_RGB";
+    m_map[GL_BLEND_SRC_RGB] = "BLEND_SRC_RGB";
+    m_map[GL_BLEND_DST_ALPHA] = "BLEND_DST_ALPHA";
+    m_map[GL_BLEND_SRC_ALPHA] = "BLEND_SRC_ALPHA";
+    m_map[GL_CONSTANT_COLOR] = "CONSTANT_COLOR";
+    m_map[GL_ONE_MINUS_CONSTANT_COLOR] = "ONE_MINUS_CONSTANT_COLOR";
+    m_map[GL_CONSTANT_ALPHA] = "CONSTANT_ALPHA";
+    m_map[GL_ONE_MINUS_CONSTANT_ALPHA] = "ONE_MINUS_CONSTANT_ALPHA";
+    m_map[GL_BLEND_COLOR] = "BLEND_COLOR";
+
+    m_map[GL_ARRAY_BUFFER] = "ARRAY_BUFFER";
+    m_map[GL_ELEMENT_ARRAY_BUFFER] = "ELEMENT_ARRAY_BUFFER";
+    m_map[GL_ARRAY_BUFFER_BINDING] = "ARRAY_BUFFER_BINDING";
+    m_map[GL_ELEMENT_ARRAY_BUFFER_BINDING] = "ELEMENT_ARRAY_BUFFER_BINDING";
+
+    m_map[GL_STREAM_DRAW] = "STREAM_DRAW";
+    m_map[GL_STATIC_DRAW] = "STATIC_DRAW";
+    m_map[GL_DYNAMIC_DRAW] = "DYNAMIC_DRAW";
+
+    m_map[GL_BUFFER_SIZE] = "BUFFER_SIZE";
+    m_map[GL_BUFFER_USAGE] = "BUFFER_USAGE";
+
+    m_map[GL_CURRENT_VERTEX_ATTRIB] = "CURRENT_VERTEX_ATTRIB";
+
+    m_map[GL_FRONT] = "FRONT";
+    m_map[GL_BACK] = "BACK";
+    m_map[GL_FRONT_AND_BACK] = "FRONT_AND_BACK";
+
+    m_map[GL_CULL_FACE] = "CULL_FACE";
+    m_map[GL_BLEND] = "BLEND";
+    m_map[GL_DITHER] = "DITHER";
+    m_map[GL_STENCIL_TEST] = "STENCIL_TEST";
+    m_map[GL_DEPTH_TEST] = "DEPTH_TEST";
+    m_map[GL_SCISSOR_TEST] = "SCISSOR_TEST";
+    m_map[GL_POLYGON_OFFSET_FILL] = "POLYGON_OFFSET_FILL";
+    m_map[GL_SAMPLE_ALPHA_TO_COVERAGE] = "SAMPLE_ALPHA_TO_COVERAGE";
+    m_map[GL_SAMPLE_COVERAGE] = "SAMPLE_COVERAGE";
+
+    m_map[GL_NO_ERROR] = "NO_ERROR";
+    m_map[GL_INVALID_ENUM] = "INVALID_ENUM";
+    m_map[GL_INVALID_VALUE] = "INVALID_VALUE";
+    m_map[GL_INVALID_OPERATION] = "INVALID_OPERATION";
+    m_map[GL_OUT_OF_MEMORY] = "OUT_OF_MEMORY";
+
+    m_map[GL_CW] = "CW";
+    m_map[GL_CCW] = "CCW";
+
+    m_map[GL_LINE_WIDTH] = "LINE_WIDTH";
+    m_map[GL_ALIASED_POINT_SIZE_RANGE] = "ALIASED_POINT_SIZE_RANGE";
+    m_map[GL_ALIASED_LINE_WIDTH_RANGE] = "ALIASED_LINE_WIDTH_RANGE";
+    m_map[GL_CULL_FACE_MODE] = "CULL_FACE_MODE";
+    m_map[GL_FRONT_FACE] = "FRONT_FACE";
+    m_map[GL_DEPTH_RANGE] = "DEPTH_RANGE";
+    m_map[GL_DEPTH_WRITEMASK] = "DEPTH_WRITEMASK";
+    m_map[GL_DEPTH_CLEAR_VALUE] = "DEPTH_CLEAR_VALUE";
+    m_map[GL_DEPTH_FUNC] = "DEPTH_FUNC";
+    m_map[GL_STENCIL_CLEAR_VALUE] = "STENCIL_CLEAR_VALUE";
+    m_map[GL_STENCIL_FUNC] = "STENCIL_FUNC";
+    m_map[GL_STENCIL_FAIL] = "STENCIL_FAIL";
+    m_map[GL_STENCIL_PASS_DEPTH_FAIL] = "STENCIL_PASS_DEPTH_FAIL";
+    m_map[GL_STENCIL_PASS_DEPTH_PASS] = "STENCIL_PASS_DEPTH_PASS";
+    m_map[GL_STENCIL_REF] = "STENCIL_REF";
+    m_map[GL_STENCIL_VALUE_MASK] = "STENCIL_VALUE_MASK";
+    m_map[GL_STENCIL_WRITEMASK] = "STENCIL_WRITEMASK";
+    m_map[GL_STENCIL_BACK_FUNC] = "STENCIL_BACK_FUNC";
+    m_map[GL_STENCIL_BACK_FAIL] = "STENCIL_BACK_FAIL";
+    m_map[GL_STENCIL_BACK_PASS_DEPTH_FAIL] = "STENCIL_BACK_PASS_DEPTH_FAIL";
+    m_map[GL_STENCIL_BACK_PASS_DEPTH_PASS] = "STENCIL_BACK_PASS_DEPTH_PASS";
+    m_map[GL_STENCIL_BACK_REF] = "STENCIL_BACK_REF";
+    m_map[GL_STENCIL_BACK_VALUE_MASK] = "STENCIL_BACK_VALUE_MASK";
+    m_map[GL_STENCIL_BACK_WRITEMASK] = "STENCIL_BACK_WRITEMASK";
+    m_map[GL_VIEWPORT] = "VIEWPORT";
+    m_map[GL_SCISSOR_BOX] = "SCISSOR_BOX";
+
+    m_map[GL_COLOR_CLEAR_VALUE] = "COLOR_CLEAR_VALUE";
+    m_map[GL_COLOR_WRITEMASK] = "COLOR_WRITEMASK";
+    m_map[GL_UNPACK_ALIGNMENT] = "UNPACK_ALIGNMENT";
+    m_map[GL_PACK_ALIGNMENT] = "PACK_ALIGNMENT";
+    m_map[GL_MAX_TEXTURE_SIZE] = "MAX_TEXTURE_SIZE";
+    m_map[GL_MAX_VIEWPORT_DIMS] = "MAX_VIEWPORT_DIMS";
+    m_map[GL_SUBPIXEL_BITS] = "SUBPIXEL_BITS";
+    m_map[GL_RED_BITS] = "RED_BITS";
+    m_map[GL_GREEN_BITS] = "GREEN_BITS";
+    m_map[GL_BLUE_BITS] = "BLUE_BITS";
+    m_map[GL_ALPHA_BITS] = "ALPHA_BITS";
+    m_map[GL_DEPTH_BITS] = "DEPTH_BITS";
+    m_map[GL_STENCIL_BITS] = "STENCIL_BITS";
+    m_map[GL_POLYGON_OFFSET_UNITS] = "POLYGON_OFFSET_UNITS";
+
+    m_map[GL_POLYGON_OFFSET_FACTOR] = "POLYGON_OFFSET_FACTOR";
+    m_map[GL_TEXTURE_BINDING_2D] = "TEXTURE_BINDING_2D";
+    m_map[GL_SAMPLE_BUFFERS] = "SAMPLE_BUFFERS";
+    m_map[GL_SAMPLES] = "SAMPLES";
+    m_map[GL_SAMPLE_COVERAGE_VALUE] = "SAMPLE_COVERAGE_VALUE";
+    m_map[GL_SAMPLE_COVERAGE_INVERT] = "SAMPLE_COVERAGE_INVERT";
+
+    m_map[GL_COMPRESSED_TEXTURE_FORMATS] = "COMPRESSED_TEXTURE_FORMATS";
+
+    m_map[GL_DONT_CARE] = "DONT_CARE";
+    m_map[GL_FASTEST] = "FASTEST";
+    m_map[GL_NICEST] = "NICEST";
+
+    m_map[GL_GENERATE_MIPMAP_HINT] = "GENERATE_MIPMAP_HINT";
+
+    m_map[GL_BYTE] = "BYTE";
+    m_map[GL_UNSIGNED_BYTE] = "UNSIGNED_BYTE";
+    m_map[GL_SHORT] = "SHORT";
+    m_map[GL_UNSIGNED_SHORT] = "UNSIGNED_SHORT";
+    m_map[GL_INT] = "INT";
+    m_map[GL_UNSIGNED_INT] = "UNSIGNED_INT";
+    m_map[GL_FLOAT] = "FLOAT";
+
+    m_map[GL_DEPTH_COMPONENT] = "DEPTH_COMPONENT";
+    m_map[GL_ALPHA] = "ALPHA";
+    m_map[GL_RGB] = "RGB";
+    m_map[GL_RGBA] = "RGBA";
+    m_map[GL_LUMINANCE] = "LUMINANCE";
+    m_map[GL_LUMINANCE_ALPHA] = "LUMINANCE_ALPHA";
+
+    m_map[GL_UNSIGNED_SHORT_4_4_4_4] = "UNSIGNED_SHORT_4_4_4_4";
+    m_map[GL_UNSIGNED_SHORT_5_5_5_1] = "UNSIGNED_SHORT_5_5_5_1";
+    m_map[GL_UNSIGNED_SHORT_5_6_5] = "UNSIGNED_SHORT_5_6_5";
+
+    m_map[GL_FRAGMENT_SHADER] = "FRAGMENT_SHADER";
+    m_map[GL_VERTEX_SHADER] = "VERTEX_SHADER";
+    m_map[GL_MAX_VERTEX_ATTRIBS] = "MAX_VERTEX_ATTRIBS";
+    m_map[GL_MAX_VERTEX_UNIFORM_VECTORS] = "MAX_VERTEX_UNIFORM_VECTORS";
+    m_map[GL_MAX_VARYING_VECTORS] = "MAX_VARYING_VECTORS";
+    m_map[GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS] = "MAX_COMBINED_TEXTURE_IMAGE_UNITS";
+    m_map[GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS] = "MAX_VERTEX_TEXTURE_IMAGE_UNITS";
+    m_map[GL_MAX_TEXTURE_IMAGE_UNITS] = "MAX_TEXTURE_IMAGE_UNITS";
+    m_map[GL_MAX_FRAGMENT_UNIFORM_VECTORS] = "MAX_FRAGMENT_UNIFORM_VECTORS";
+    m_map[GL_SHADER_TYPE] = "SHADER_TYPE";
+    m_map[GL_DELETE_STATUS] = "DELETE_STATUS";
+    m_map[GL_LINK_STATUS] = "LINK_STATUS";
+    m_map[GL_VALIDATE_STATUS] = "VALIDATE_STATUS";
+    m_map[GL_ATTACHED_SHADERS] = "ATTACHED_SHADERS";
+    m_map[GL_ACTIVE_UNIFORMS] = "ACTIVE_UNIFORMS";
+    m_map[GL_ACTIVE_ATTRIBUTES] = "ACTIVE_ATTRIBUTES";
+    m_map[GL_SHADING_LANGUAGE_VERSION] = "SHADING_LANGUAGE_VERSION";
+    m_map[GL_CURRENT_PROGRAM] = "CURRENT_PROGRAM";
+
+    m_map[GL_NEVER] = "NEVER";
+    m_map[GL_LESS] = "LESS";
+    m_map[GL_EQUAL] = "EQUAL";
+    m_map[GL_LEQUAL] = "LEQUAL";
+    m_map[GL_GREATER] = "GREATER";
+    m_map[GL_NOTEQUAL] = "NOTEQUAL";
+    m_map[GL_GEQUAL] = "GEQUAL";
+    m_map[GL_ALWAYS] = "ALWAYS";
+
+    m_map[GL_KEEP] = "KEEP";
+    m_map[GL_REPLACE] = "REPLACE";
+    m_map[GL_INCR] = "INCR";
+    m_map[GL_DECR] = "DECR";
+    m_map[GL_INVERT] = "INVERT";
+    m_map[GL_INCR_WRAP] = "INCR_WRAP";
+    m_map[GL_DECR_WRAP] = "DECR_WRAP";
+
+    m_map[GL_VENDOR] = "VENDOR";
+    m_map[GL_RENDERER] = "RENDERER";
+    m_map[GL_VERSION] = "VERSION";
+
+    m_map[GL_NEAREST] = "NEAREST";
+    m_map[GL_LINEAR] = "LINEAR";
+
+    m_map[GL_NEAREST_MIPMAP_NEAREST] = "NEAREST_MIPMAP_NEAREST";
+    m_map[GL_LINEAR_MIPMAP_NEAREST] = "LINEAR_MIPMAP_NEAREST";
+    m_map[GL_NEAREST_MIPMAP_LINEAR] = "NEAREST_MIPMAP_LINEAR";
+    m_map[GL_LINEAR_MIPMAP_LINEAR] = "LINEAR_MIPMAP_LINEAR";
+
+    m_map[GL_TEXTURE_MAG_FILTER] = "TEXTURE_MAG_FILTER";
+    m_map[GL_TEXTURE_MIN_FILTER] = "TEXTURE_MIN_FILTER";
+    m_map[GL_TEXTURE_WRAP_S] = "TEXTURE_WRAP_S";
+    m_map[GL_TEXTURE_WRAP_T] = "TEXTURE_WRAP_T";
+
+    m_map[GL_TEXTURE_2D] = "TEXTURE_2D";
+    m_map[GL_TEXTURE] = "TEXTURE";
+
+    m_map[GL_TEXTURE_CUBE_MAP] = "TEXTURE_CUBE_MAP";
+    m_map[GL_TEXTURE_BINDING_CUBE_MAP] = "TEXTURE_BINDING_CUBE_MAP";
+    m_map[GL_TEXTURE_CUBE_MAP_POSITIVE_X] = "TEXTURE_CUBE_MAP_POSITIVE_X";
+    m_map[GL_TEXTURE_CUBE_MAP_NEGATIVE_X] = "TEXTURE_CUBE_MAP_NEGATIVE_X";
+    m_map[GL_TEXTURE_CUBE_MAP_POSITIVE_Y] = "TEXTURE_CUBE_MAP_POSITIVE_Y";
+    m_map[GL_TEXTURE_CUBE_MAP_NEGATIVE_Y] = "TEXTURE_CUBE_MAP_NEGATIVE_Y";
+    m_map[GL_TEXTURE_CUBE_MAP_POSITIVE_Z] = "TEXTURE_CUBE_MAP_POSITIVE_Z";
+    m_map[GL_TEXTURE_CUBE_MAP_NEGATIVE_Z] = "TEXTURE_CUBE_MAP_NEGATIVE_Z";
+    m_map[GL_MAX_CUBE_MAP_TEXTURE_SIZE] = "MAX_CUBE_MAP_TEXTURE_SIZE";
+
+    m_map[GL_TEXTURE0] = "TEXTURE0";
+    m_map[GL_TEXTURE1] = "TEXTURE1";
+    m_map[GL_TEXTURE2] = "TEXTURE2";
+    m_map[GL_TEXTURE3] = "TEXTURE3";
+    m_map[GL_TEXTURE4] = "TEXTURE4";
+    m_map[GL_TEXTURE5] = "TEXTURE5";
+    m_map[GL_TEXTURE6] = "TEXTURE6";
+    m_map[GL_TEXTURE7] = "TEXTURE7";
+    m_map[GL_TEXTURE8] = "TEXTURE8";
+    m_map[GL_TEXTURE9] = "TEXTURE9";
+    m_map[GL_TEXTURE10] = "TEXTURE10";
+    m_map[GL_TEXTURE11] = "TEXTURE11";
+    m_map[GL_TEXTURE12] = "TEXTURE12";
+    m_map[GL_TEXTURE13] = "TEXTURE13";
+    m_map[GL_TEXTURE14] = "TEXTURE14";
+    m_map[GL_TEXTURE15] = "TEXTURE15";
+    m_map[GL_TEXTURE16] = "TEXTURE16";
+    m_map[GL_TEXTURE17] = "TEXTURE17";
+    m_map[GL_TEXTURE18] = "TEXTURE18";
+    m_map[GL_TEXTURE19] = "TEXTURE19";
+    m_map[GL_TEXTURE20] = "TEXTURE20";
+    m_map[GL_TEXTURE21] = "TEXTURE21";
+    m_map[GL_TEXTURE22] = "TEXTURE22";
+    m_map[GL_TEXTURE23] = "TEXTURE23";
+    m_map[GL_TEXTURE24] = "TEXTURE24";
+    m_map[GL_TEXTURE25] = "TEXTURE25";
+    m_map[GL_TEXTURE26] = "TEXTURE26";
+    m_map[GL_TEXTURE27] = "TEXTURE27";
+    m_map[GL_TEXTURE28] = "TEXTURE28";
+    m_map[GL_TEXTURE29] = "TEXTURE29";
+    m_map[GL_TEXTURE30] = "TEXTURE30";
+    m_map[GL_TEXTURE31] = "TEXTURE31";
+    m_map[GL_ACTIVE_TEXTURE] = "ACTIVE_TEXTURE";
+
+    m_map[GL_REPEAT] = "REPEAT";
+    m_map[GL_CLAMP_TO_EDGE] = "CLAMP_TO_EDGE";
+    m_map[GL_MIRRORED_REPEAT] = "MIRRORED_REPEAT";
+
+    m_map[GL_FLOAT_VEC2] = "FLOAT_VEC2";
+    m_map[GL_FLOAT_VEC3] = "FLOAT_VEC3";
+    m_map[GL_FLOAT_VEC4] = "FLOAT_VEC4";
+    m_map[GL_INT_VEC2] = "INT_VEC2";
+    m_map[GL_INT_VEC3] = "INT_VEC3";
+    m_map[GL_INT_VEC4] = "INT_VEC4";
+    m_map[GL_BOOL] = "BOOL";
+    m_map[GL_BOOL_VEC2] = "BOOL_VEC2";
+    m_map[GL_BOOL_VEC3] = "BOOL_VEC3";
+    m_map[GL_BOOL_VEC4] = "BOOL_VEC4";
+    m_map[GL_FLOAT_MAT2] = "FLOAT_MAT2";
+    m_map[GL_FLOAT_MAT3] = "FLOAT_MAT3";
+    m_map[GL_FLOAT_MAT4] = "FLOAT_MAT4";
+    m_map[GL_SAMPLER_2D] = "SAMPLER_2D";
+    m_map[GL_SAMPLER_CUBE] = "SAMPLER_CUBE";
+
+    m_map[GL_VERTEX_ATTRIB_ARRAY_ENABLED] = "VERTEX_ATTRIB_ARRAY_ENABLED";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_SIZE] = "VERTEX_ATTRIB_ARRAY_SIZE";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_STRIDE] = "VERTEX_ATTRIB_ARRAY_STRIDE";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_TYPE] = "VERTEX_ATTRIB_ARRAY_TYPE";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_NORMALIZED] = "VERTEX_ATTRIB_ARRAY_NORMALIZED";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_POINTER] = "VERTEX_ATTRIB_ARRAY_POINTER";
+    m_map[GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING] = "VERTEX_ATTRIB_ARRAY_BUFFER_BINDING";
+
+    m_map[GL_COMPILE_STATUS] = "COMPILE_STATUS";
+
+    m_map[GL_LOW_FLOAT] = "LOW_FLOAT";
+    m_map[GL_MEDIUM_FLOAT] = "MEDIUM_FLOAT";
+    m_map[GL_HIGH_FLOAT] = "HIGH_FLOAT";
+    m_map[GL_LOW_INT] = "LOW_INT";
+    m_map[GL_MEDIUM_INT] = "MEDIUM_INT";
+    m_map[GL_HIGH_INT] = "HIGH_INT";
+
+    m_map[GL_FRAMEBUFFER] = "FRAMEBUFFER";
+    m_map[GL_RENDERBUFFER] = "RENDERBUFFER";
+
+    m_map[GL_RGBA4] = "RGBA4";
+    m_map[GL_RGB5_A1] = "RGB5_A1";
+    m_map[GL_RGB565] = "RGB565";
+    m_map[GL_DEPTH_COMPONENT16] = "DEPTH_COMPONENT16";
+    m_map[GL_STENCIL_INDEX] = "STENCIL_INDEX";
+    m_map[GL_STENCIL_INDEX8] = "STENCIL_INDEX8";
+
+    m_map[GL_RENDERBUFFER_WIDTH] = "RENDERBUFFER_WIDTH";
+    m_map[GL_RENDERBUFFER_HEIGHT] = "RENDERBUFFER_HEIGHT";
+    m_map[GL_RENDERBUFFER_INTERNAL_FORMAT] = "RENDERBUFFER_INTERNAL_FORMAT";
+    m_map[GL_RENDERBUFFER_RED_SIZE] = "RENDERBUFFER_RED_SIZE";
+    m_map[GL_RENDERBUFFER_GREEN_SIZE] = "RENDERBUFFER_GREEN_SIZE";
+    m_map[GL_RENDERBUFFER_BLUE_SIZE] = "RENDERBUFFER_BLUE_SIZE";
+    m_map[GL_RENDERBUFFER_ALPHA_SIZE] = "RENDERBUFFER_ALPHA_SIZE";
+    m_map[GL_RENDERBUFFER_DEPTH_SIZE] = "RENDERBUFFER_DEPTH_SIZE";
+    m_map[GL_RENDERBUFFER_STENCIL_SIZE] = "RENDERBUFFER_STENCIL_SIZE";
+
+    m_map[GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE] = "FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE";
+    m_map[GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME] = "FRAMEBUFFER_ATTACHMENT_OBJECT_NAME";
+    m_map[GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL] = "FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL";
+    m_map[GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE] = "FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE";
+
+    m_map[GL_COLOR_ATTACHMENT0] = "COLOR_ATTACHMENT0";
+    m_map[GL_DEPTH_ATTACHMENT] = "DEPTH_ATTACHMENT";
+    m_map[GL_STENCIL_ATTACHMENT] = "STENCIL_ATTACHMENT";
+
+    m_map[GL_FRAMEBUFFER_COMPLETE] = "FRAMEBUFFER_COMPLETE";
+    m_map[GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT] = "FRAMEBUFFER_INCOMPLETE_ATTACHMENT";
+    m_map[GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT] = "FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT";
+    m_map[GL_FRAMEBUFFER_UNSUPPORTED] = "FRAMEBUFFER_UNSUPPORTED";
+
+    m_map[GL_FRAMEBUFFER_BINDING] = "FRAMEBUFFER_BINDING";
+    m_map[GL_RENDERBUFFER_BINDING] = "RENDERBUFFER_BINDING";
+    m_map[GL_MAX_RENDERBUFFER_SIZE] = "MAX_RENDERBUFFER_SIZE";
+
+    m_map[GL_INVALID_FRAMEBUFFER_OPERATION] = "INVALID_FRAMEBUFFER_OPERATION";
+}
+
+QString EnumToStringMap::lookUp(const GLuint value) const
+{
+    if (m_map.contains(value))
+        return m_map[value];
+
+    return QString("0x0%1").arg(value, 0, 16);
+}
+
diff --git a/src/datavisualizationqml2/enumtostringmap_p.h b/src/datavisualizationqml2/enumtostringmap_p.h
new file mode 100644
index 00000000..2206f153
--- /dev/null
+++ b/src/datavisualizationqml2/enumtostringmap_p.h
@@ -0,0 +1,49 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc
+** All rights reserved.
+** For any questions to Digia, please use contact form at http://qt.digia.com
+**
+** This file is part of the QtDataVisualization module.
+**
+** 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 Digia.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://qt.digia.com
+**
+****************************************************************************/
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the QtDataVisualization API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+
+#ifndef ENUMTOSTRINGMAP_P_H
+#define ENUMTOSTRINGMAP_P_H
+
+#include <QtGui/qopengl.h>
+#include <QMap>
+#include <QString>
+
+class EnumToStringMap
+{
+public:
+    static EnumToStringMap *newInstance();
+    static void deleteInstance();
+    QString lookUp(const GLuint value) const;
+
+private:
+    EnumToStringMap();
+    QMap<int, QString> m_map;
+    QString m_unknown;
+};
+
+#endif
diff --git a/src/datavisualizationqml2/glstatestore.cpp b/src/datavisualizationqml2/glstatestore.cpp
new file mode 100644
index 00000000..f053078b
--- /dev/null
+++ b/src/datavisualizationqml2/glstatestore.cpp
@@ -0,0 +1,377 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc
+** All rights reserved.
+** For any questions to Digia, please use contact form at http://qt.digia.com
+**
+** This file is part of the QtDataVisualization module.
+**
+** 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 Digia.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://qt.digia.com
+**
+****************************************************************************/
+#include "glstatestore_p.h"
+#include <QDebug>
+#include <QColor>
+#include <QFile>
+
+#ifdef VERBOSE_STATE_STORE
+static QFile *beforeFile = 0;
+static QFile *afterFile = 0;
+#endif
+
+GLStateStore::GLStateStore(QOpenGLContext *context, QObject *parent) :
+    QObject(parent),
+    QOpenGLFunctions(context)
+  #ifdef VERBOSE_STATE_STORE
+  , m_map(EnumToStringMap::newInstance())
+  #endif
+{
+    GLint maxVertexAttribs;
+    glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &maxVertexAttribs);
+
+#ifdef VERBOSE_STATE_STORE
+    qDebug() << "GL_MAX_VERTEX_ATTRIBS: " << maxVertexAttribs;
+    if (!beforeFile) {
+        beforeFile = new QFile(QStringLiteral("state_before.txt"));
+        afterFile = new QFile(QStringLiteral("state_after.txt"));
+        beforeFile->open(QIODevice::WriteOnly);
+        afterFile->open(QIODevice::WriteOnly);
+        QDebug beforeInit(beforeFile);
+        QDebug afterInit(afterFile);
+        beforeInit << "GL states before 'context switch'" << endl;
+        afterInit << "GL states after 'context switch'" << endl;
+    }
+#endif
+
+    m_maxVertexAttribs = qMin(maxVertexAttribs, 2); // Datavis only uses 2 attribs max
+    m_vertexAttribArrayEnabledStates = new GLint[maxVertexAttribs];
+    m_vertexAttribArrayBoundBuffers = new GLint[maxVertexAttribs];
+    m_vertexAttribArraySizes = new GLint[maxVertexAttribs];
+    m_vertexAttribArrayTypes = new GLint[maxVertexAttribs];
+    m_vertexAttribArrayNormalized = new GLint[maxVertexAttribs];
+    m_vertexAttribArrayStrides = new GLint[maxVertexAttribs];
+    m_vertexAttribArrayOffsets = new GLint[maxVertexAttribs];
+
+    initGLDefaultState();
+}
+
+GLStateStore::~GLStateStore()
+{
+#ifdef VERBOSE_STATE_STORE
+    EnumToStringMap::deleteInstance();
+    m_map = 0;
+#endif
+    delete m_vertexAttribArrayEnabledStates;
+    delete m_vertexAttribArrayBoundBuffers;
+}
+
+void GLStateStore::storeGLState()
+{
+#ifdef VERBOSE_STATE_STORE
+    printCurrentState(true);
+#endif
+
+#if !defined(QT_OPENGL_ES_2)
+    glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &m_drawFramebuffer);
+    glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &m_readFramebuffer);
+#endif
+    glGetIntegerv(GL_RENDERBUFFER_BINDING, &m_renderbuffer);
+    glGetFloatv(GL_COLOR_CLEAR_VALUE, m_clearColor);
+    m_isBlendingEnabled = glIsEnabled(GL_BLEND);
+    m_isDepthTestEnabled = glIsEnabled(GL_DEPTH_TEST);
+    glGetBooleanv(GL_DEPTH_WRITEMASK, &m_isDepthWriteEnabled);
+    glGetFloatv(GL_DEPTH_CLEAR_VALUE, &m_clearDepth);
+    glGetIntegerv(GL_DEPTH_FUNC, &m_depthFunc);
+    glGetBooleanv(GL_POLYGON_OFFSET_FILL, &m_polygonOffsetFillEnabled);
+    glGetFloatv(GL_POLYGON_OFFSET_FACTOR, &m_polygonOffsetFactor);
+    glGetFloatv(GL_POLYGON_OFFSET_UNITS, &m_polygonOffsetUnits);
+
+    glGetIntegerv(GL_CURRENT_PROGRAM, &m_currentProgram);
+    glGetIntegerv(GL_ACTIVE_TEXTURE, &m_activeTexture);
+    glGetIntegerv(GL_TEXTURE_BINDING_2D, &m_texBinding2D);
+    glGetIntegerv(GL_FRONT_FACE, &m_frontFace);
+    m_isCullFaceEnabled = glIsEnabled(GL_CULL_FACE);
+    glGetIntegerv(GL_CULL_FACE_MODE, &m_cullFaceMode);
+    glGetIntegerv(GL_BLEND_EQUATION_RGB, &m_blendEquationRGB);
+    glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &m_blendEquationAlpha);
+    glGetIntegerv(GL_BLEND_DST_ALPHA, &m_blendDestAlpha);
+    glGetIntegerv(GL_BLEND_DST_RGB, &m_blendDestRGB);
+    glGetIntegerv(GL_BLEND_SRC_ALPHA, &m_blendSrcAlpha);
+    glGetIntegerv(GL_BLEND_SRC_RGB, &m_blendSrcRGB);
+    glGetIntegerv(GL_SCISSOR_BOX, m_scissorBox);
+    m_isScissorTestEnabled = glIsEnabled(GL_SCISSOR_TEST);
+
+    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &m_boundArrayBuffer);
+    glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &m_boundElementArrayBuffer);
+
+    for (int i = 0; i < m_maxVertexAttribs;i++) {
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &m_vertexAttribArrayEnabledStates[i]);
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING, &m_vertexAttribArrayBoundBuffers[i]);
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_SIZE, &m_vertexAttribArraySizes[i]);
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_TYPE, &m_vertexAttribArrayTypes[i]);
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_NORMALIZED, &m_vertexAttribArrayNormalized[i]);
+        glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_STRIDE, &m_vertexAttribArrayStrides[i]);
+    }
+}
+
+#ifdef VERBOSE_STATE_STORE
+void GLStateStore::printCurrentState(bool in)
+{
+    QFile *file;
+    if (in)
+        file = beforeFile;
+    else
+        file = afterFile;
+
+    if (file->isOpen()) {
+        QDebug msg(file);
+#if !defined(QT_OPENGL_ES_2)
+        GLint drawFramebuffer;
+        GLint readFramebuffer;
+#endif
+        GLint renderbuffer;
+        GLfloat clearColor[4];
+        GLfloat clearDepth;
+        GLboolean isBlendingEnabled = glIsEnabled(GL_BLEND);
+        GLboolean isDepthTestEnabled = glIsEnabled(GL_DEPTH_TEST);
+        GLint depthFunc;
+        GLboolean isDepthWriteEnabled;
+        GLint currentProgram;
+        GLint *vertexAttribArrayEnabledStates = new GLint[m_maxVertexAttribs];
+        GLint *vertexAttribArrayBoundBuffers = new GLint[m_maxVertexAttribs];
+        GLint *vertexAttribArraySizes = new GLint[m_maxVertexAttribs];
+        GLint *vertexAttribArrayTypes = new GLint[m_maxVertexAttribs];
+        GLint *vertexAttribArrayNormalized = new GLint[m_maxVertexAttribs];
+        GLint *vertexAttribArrayStrides = new GLint[m_maxVertexAttribs];
+        GLint activeTexture;
+        GLint texBinding2D;
+        GLint arrayBufferBinding;
+        GLint frontFace;
+        GLboolean isCullFaceEnabled = glIsEnabled(GL_CULL_FACE);
+        GLint cullFaceMode;
+        GLint blendEquationRGB;
+        GLint blendEquationAlpha;
+
+        GLint blendDestAlpha;
+        GLint blendDestRGB;
+        GLint blendSrcAlpha;
+        GLint blendSrcRGB;
+        GLint scissorBox[4];
+        GLboolean isScissorTestEnabled = glIsEnabled(GL_SCISSOR_TEST);
+        GLint boundElementArrayBuffer;
+        GLboolean polygonOffsetFillEnabled;
+        GLfloat polygonOffsetFactor;
+        GLfloat polygonOffsetUnits;
+
+        glGetBooleanv(GL_DEPTH_WRITEMASK, &isDepthWriteEnabled);
+#if !defined(QT_OPENGL_ES_2)
+        glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &drawFramebuffer);
+        glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &readFramebuffer);
+#endif
+        glGetIntegerv(GL_RENDERBUFFER_BINDING, &renderbuffer);
+        glGetFloatv(GL_COLOR_CLEAR_VALUE, clearColor);
+        glGetFloatv(GL_DEPTH_CLEAR_VALUE, &clearDepth);
+        glGetIntegerv(GL_DEPTH_FUNC, &depthFunc);
+        glGetBooleanv(GL_POLYGON_OFFSET_FILL, &polygonOffsetFillEnabled);
+        glGetFloatv(GL_POLYGON_OFFSET_FACTOR, &polygonOffsetFactor);
+        glGetFloatv(GL_POLYGON_OFFSET_UNITS, &polygonOffsetUnits);
+
+        glGetIntegerv(GL_CURRENT_PROGRAM, &currentProgram);
+        glGetIntegerv(GL_ACTIVE_TEXTURE, &activeTexture);
+        glGetIntegerv(GL_TEXTURE_BINDING_2D, &texBinding2D );
+        glGetIntegerv(GL_FRONT_FACE, &frontFace);
+        glGetIntegerv(GL_CULL_FACE_MODE, &cullFaceMode);
+        glGetIntegerv(GL_BLEND_EQUATION_RGB, &blendEquationRGB);
+        glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &blendEquationAlpha);
+        glGetIntegerv(GL_BLEND_DST_ALPHA, &blendDestAlpha);
+        glGetIntegerv(GL_BLEND_DST_RGB, &blendDestRGB);
+        glGetIntegerv(GL_BLEND_SRC_ALPHA, &blendSrcAlpha);
+        glGetIntegerv(GL_BLEND_SRC_RGB, &blendSrcRGB);
+        glGetIntegerv(GL_SCISSOR_BOX, scissorBox);
+        glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &boundElementArrayBuffer);
+        glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &arrayBufferBinding);
+
+        for (int i = 0; i < m_maxVertexAttribs;i++) {
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &vertexAttribArrayEnabledStates[i]);
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING, &vertexAttribArrayBoundBuffers[i]);
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_SIZE, &vertexAttribArraySizes[i]);
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_TYPE, &vertexAttribArrayTypes[i]);
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_NORMALIZED, &vertexAttribArrayNormalized[i]);
+            glGetVertexAttribiv(i, GL_VERTEX_ATTRIB_ARRAY_STRIDE, &vertexAttribArrayStrides[i]);
+        }
+
+        QColor color;
+        color.setRgbF(clearColor[0], clearColor[1], clearColor[2]);
+        color.setAlphaF(clearColor[3]);
+
+#if !defined(QT_OPENGL_ES_2)
+        msg << "---" << endl;
+        msg << "    GL_DRAW_FRAMEBUFFER_BINDING "<< drawFramebuffer << endl;
+        msg << "    GL_READ_FRAMEBUFFER_BINDING "<< readFramebuffer << endl;
+#endif
+        msg << "    GL_RENDERBUFFER_BINDING " << renderbuffer << endl;
+        msg << "    GL_SCISSOR_TEST " << bool(isScissorTestEnabled) << endl;
+        msg << "    GL_SCISSOR_BOX " << m_scissorBox[0] << m_scissorBox[1] << m_scissorBox[2]
+            << m_scissorBox[3] << endl;
+        msg << "    GL_COLOR_CLEAR_VALUE "<< color << endl;
+        msg << "    GL_DEPTH_CLEAR_VALUE "<< clearDepth << endl;
+        msg << "    GL_BLEND "<< bool(isBlendingEnabled) << endl;
+        msg << "    GL_BLEND_EQUATION_RGB" << m_map->lookUp(blendEquationRGB) << endl;
+        msg << "    GL_BLEND_EQUATION_ALPHA" << m_map->lookUp(blendEquationAlpha) << endl;
+        msg << "    GL_BLEND_DST_ALPHA" << m_map->lookUp(blendDestAlpha) << endl;
+        msg << "    GL_BLEND_DST_RGB" << m_map->lookUp(blendDestRGB) << endl;
+        msg << "    GL_BLEND_SRC_ALPHA" << m_map->lookUp(blendSrcAlpha) << endl;
+        msg << "    GL_BLEND_SRC_RGB" << m_map->lookUp(blendSrcRGB) << endl;
+        msg << "    GL_DEPTH_TEST "<< bool(isDepthTestEnabled) << endl;
+        msg << "    GL_DEPTH_WRITEMASK "<< bool(isDepthWriteEnabled) << endl;
+        msg << "    GL_POLYGON_OFFSET_FILL" << bool(polygonOffsetFillEnabled) << endl;
+        msg << "    GL_POLYGON_OFFSET_FACTOR "<< polygonOffsetFactor << endl;
+        msg << "    GL_POLYGON_OFFSET_UNITS "<< polygonOffsetUnits << endl;
+        msg << "    GL_CULL_FACE "<< bool(isCullFaceEnabled) << endl;
+        msg << "    GL_CULL_FACE_MODE "<< m_map->lookUp(cullFaceMode) << endl;
+        msg << "    GL_DEPTH_FUNC "<< m_map->lookUp(depthFunc) << endl;
+        msg << "    GL_FRONT_FACE "<< m_map->lookUp(frontFace) << endl;
+        msg << "    GL_CURRENT_PROGRAM "<< currentProgram << endl;
+        msg << "    GL_ACTIVE_TEXTURE "<< QString("0x%1").arg(activeTexture, 0, 16) << endl;
+        msg << "    GL_TEXTURE_BINDING_2D "<< texBinding2D << endl;
+        msg << "    GL_ELEMENT_ARRAY_BUFFER_BINDING "<< boundElementArrayBuffer << endl;
+        msg << "    GL_ARRAY_BUFFER_BINDING "<< arrayBufferBinding << endl;
+        for (int i = 0; i < m_maxVertexAttribs;i++) {
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_ENABLED "<< i << "       = "
+                <<  bool(vertexAttribArrayEnabledStates[i]) << endl;
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING"<< i << " = "
+                <<  vertexAttribArrayBoundBuffers[i] << endl;
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_SIZE"<< i << " = "
+                <<  vertexAttribArraySizes[i] << endl;
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_TYPE"<< i << " = "
+                <<  vertexAttribArrayTypes[i] << endl;
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_NORMALIZED"<< i << " = "
+                <<  vertexAttribArrayNormalized[i] << endl;
+            msg << "    GL_VERTEX_ATTRIB_ARRAY_STRIDE"<< i << " = "
+                <<  vertexAttribArrayStrides[i] << endl;
+        }
+    }
+}
+#endif
+
+void GLStateStore::restoreGLState()
+{
+#if !defined(QT_OPENGL_ES_2)
+    glBindFramebuffer(GL_READ_FRAMEBUFFER, m_readFramebuffer);
+    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, m_drawFramebuffer);
+#endif
+    glBindRenderbuffer(GL_RENDERBUFFER_BINDING, m_renderbuffer);
+
+    if (m_isScissorTestEnabled)
+        glEnable(GL_SCISSOR_TEST);
+    else
+        glDisable(GL_SCISSOR_TEST);
+
+    glScissor(m_scissorBox[0], m_scissorBox[1], m_scissorBox[2], m_scissorBox[3]);
+    glClearColor(m_clearColor[0], m_clearColor[1], m_clearColor[2], m_clearColor[3]);
+    glClearDepthf(m_clearDepth);
+    if (m_isBlendingEnabled)
+        glEnable(GL_BLEND);
+    else
+        glDisable(GL_BLEND);
+
+    if (m_isDepthTestEnabled)
+        glEnable(GL_DEPTH_TEST);
+    else
+        glDisable(GL_DEPTH_TEST);
+
+    if (m_isCullFaceEnabled)
+        glEnable(GL_CULL_FACE);
+    else
+        glDisable(GL_CULL_FACE);
+
+    glCullFace(m_cullFaceMode);
+
+    glBlendEquationSeparate(m_blendEquationRGB, m_blendEquationAlpha);
+    glBlendFuncSeparate(m_blendSrcRGB, m_blendDestRGB, m_blendSrcAlpha, m_blendDestAlpha);
+
+    glDepthMask(m_isDepthWriteEnabled);
+    glDepthFunc(m_depthFunc);
+    glFrontFace(m_frontFace);
+
+    if (m_polygonOffsetFillEnabled)
+        glEnable(GL_POLYGON_OFFSET_FILL);
+    else
+        glDisable(GL_POLYGON_OFFSET_FILL);
+
+    glPolygonOffset(m_polygonOffsetFactor, m_polygonOffsetUnits);
+
+    glUseProgram(m_currentProgram);
+
+    glActiveTexture(m_activeTexture);
+    glBindTexture(GL_TEXTURE_2D, m_texBinding2D);
+
+    // Restore bound element array buffer and array buffers
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_boundElementArrayBuffer);
+    for (int i = 0; i < m_maxVertexAttribs; i++) {
+        if (m_vertexAttribArrayEnabledStates[i])
+            glEnableVertexAttribArray(i);
+        else
+            glDisableVertexAttribArray(i);
+
+        glBindBuffer(GL_ARRAY_BUFFER, m_vertexAttribArrayBoundBuffers[i]);
+        glVertexAttribPointer(i, m_vertexAttribArraySizes[i],
+                              m_vertexAttribArrayTypes[i],
+                              m_vertexAttribArrayNormalized[i],
+                              m_vertexAttribArrayStrides[i],
+                              (void *) m_vertexAttribArrayOffsets[i]);
+    }
+
+    glBindBuffer(GL_ARRAY_BUFFER, m_boundArrayBuffer);
+
+#ifdef VERBOSE_STATE_STORE
+    printCurrentState(false);
+#endif
+}
+
+void GLStateStore::initGLDefaultState()
+{
+#if !defined(QT_OPENGL_ES_2)
+    m_drawFramebuffer = 0;
+    m_readFramebuffer = 0;
+#endif
+    m_renderbuffer = 0;
+    m_clearColor[0] = m_clearColor[1] = m_clearColor[2] = m_clearColor[3] = 1.0f;
+    m_clearDepth = 1.0f;
+    m_isBlendingEnabled = GL_FALSE;
+    m_isDepthTestEnabled = GL_FALSE;
+    m_depthFunc = GL_LESS;
+    m_isDepthWriteEnabled = GL_TRUE;
+    m_currentProgram = 0;
+    m_texBinding2D = 0;
+    for (int i = 0; i < m_maxVertexAttribs;i++) {
+        m_vertexAttribArrayEnabledStates[i] = GL_FALSE;
+        m_vertexAttribArrayBoundBuffers[i] = 0;
+        m_vertexAttribArraySizes[i] = 4;
+        m_vertexAttribArrayTypes[i] = GL_FLOAT;
+        m_vertexAttribArrayNormalized[i] = GL_FALSE;
+        m_vertexAttribArrayStrides[i] = 0;
+        m_vertexAttribArrayOffsets[i] = 0;
+    }
+    m_activeTexture = GL_TEXTURE0;
+    m_frontFace = GL_CCW;
+    m_isCullFaceEnabled = false;
+    m_cullFaceMode = GL_BACK;
+    m_blendEquationRGB = GL_FUNC_ADD;
+    m_blendEquationAlpha = GL_FUNC_ADD;
+    m_scissorBox[0] = 0;
+    m_scissorBox[1] = 0;
+    m_scissorBox[2] = 0;
+    m_scissorBox[3] = 0;
+    m_isScissorTestEnabled = GL_FALSE;
+
+    m_polygonOffsetFillEnabled = GL_FALSE;
+    m_polygonOffsetFactor = 0.0;
+    m_polygonOffsetUnits = 0.0;
+}
diff --git a/src/datavisualizationqml2/glstatestore_p.h b/src/datavisualizationqml2/glstatestore_p.h
new file mode 100644
index 00000000..560598bf
--- /dev/null
+++ b/src/datavisualizationqml2/glstatestore_p.h
@@ -0,0 +1,99 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc
+** All rights reserved.
+** For any questions to Digia, please use contact form at http://qt.digia.com
+**
+** This file is part of the QtDataVisualization module.
+**
+** 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 Digia.
+**
+** If you have questions regarding the use of this file, please use
+** contact form at http://qt.digia.com
+**
+****************************************************************************/
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the QtDataVisualization API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+
+#ifndef GLSTATESTORE_P_H
+#define GLSTATESTORE_P_H
+
+//#define VERBOSE_STATE_STORE
+
+#include <QObject>
+#include <QtGui/QOpenGLFunctions>
+#include <QtGui/QOpenGLContext>
+#ifdef VERBOSE_STATE_STORE
+#include "enumtostringmap_p.h"
+#endif
+
+class GLStateStore : public QObject, protected QOpenGLFunctions
+{
+    Q_OBJECT
+public:
+    explicit GLStateStore(QOpenGLContext *context, QObject *parent = 0);
+    ~GLStateStore();
+
+    void storeGLState();
+    void restoreGLState();
+    void initGLDefaultState();
+
+#ifdef VERBOSE_STATE_STORE
+    void printCurrentState(bool in);
+    EnumToStringMap *m_map;
+#endif
+
+    GLint m_scissorBox[4];
+    GLboolean m_isScissorTestEnabled;
+
+#if !defined(QT_OPENGL_ES_2)
+    GLint m_drawFramebuffer;
+    GLint m_readFramebuffer;
+#endif
+    GLint m_renderbuffer;
+    GLfloat m_clearColor[4];
+    GLfloat m_clearDepth;
+    GLboolean m_isBlendingEnabled;
+    GLboolean m_isDepthTestEnabled;
+    GLint m_depthFunc;
+    GLboolean m_isDepthWriteEnabled;
+    GLint m_currentProgram;
+    GLint m_maxVertexAttribs;
+    GLint *m_vertexAttribArrayEnabledStates;
+    GLint *m_vertexAttribArrayBoundBuffers;
+    GLint *m_vertexAttribArraySizes;
+    GLint *m_vertexAttribArrayTypes;
+    GLint *m_vertexAttribArrayNormalized;
+    GLint *m_vertexAttribArrayStrides;
+    GLint *m_vertexAttribArrayOffsets;
+
+    GLint m_activeTexture;
+    GLint m_texBinding2D;
+    GLint m_frontFace;
+    GLboolean m_isCullFaceEnabled;
+    GLint m_cullFaceMode;
+    GLint m_blendEquationRGB;
+    GLint m_blendEquationAlpha;
+    GLint m_blendDestAlpha;
+    GLint m_blendDestRGB;
+    GLint m_blendSrcAlpha;
+    GLint m_blendSrcRGB;
+    GLint m_boundArrayBuffer;
+    GLint m_boundElementArrayBuffer;
+    GLboolean m_polygonOffsetFillEnabled;
+    GLfloat m_polygonOffsetFactor;
+    GLfloat m_polygonOffsetUnits;
+};
+
+#endif