Merge lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider into lp:ubuntu-docviewer-app

[Stefano Verzegnassi]

Use QQuickAsyncImageProvider in LOPartsImageProvider class.
This is backported on Ubuntu/Ubuntu Touch since Qt 5.4.1-1ubuntu7.
On any other distro/OS it works only with Qt 5.6 (or later).

Use QQuickAsyncImageProvider in LOPartsImageProvider class.

This is backported on Ubuntu/Ubuntu Touch since Qt 5.4.1-1ubuntu7.
On any other distro/OS it works only with Qt 5.6 (or later).

[Stefano Verzegnassi (verzegnassi-stefano)]

@Roman, we still have to discuss about the line 398 of the diff... :)

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:248
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/89/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/444/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/89/rebuild

review: Needs Fixing (continuous-integration)

[Roman Shchekin (mrqtros)]

Just remove it and manage memory yourself (in "slotTaskRenderFinished" and "cancel").

[Stefano Verzegnassi (verzegnassi-stefano)]

By doing so, the app crashes any time a document is loaded.

It does not crash always at the same point, but it may occur at two different points:

1) In the internalRenderCallback, when it calls "doNextTask()", it crashes at line 84 of the renderengine.cpp

    if (m_activeTaskCount && !task->canBeRunInParallel(m_lastTask))
        return;

2) In lopartsimageresponse.cpp, when deleting m_task. (No other info is visible on the debugger)

void LOPartsImageResponse::cancel()
{
    disconnect(RenderEngine::instance(), &RenderEngine::taskRenderFinished,
               this, &LOPartsImageResponse::slotTaskRenderFinished);

    if (m_task) {
        QMetaObject::invokeMethod(RenderEngine::instance(), "dequeueTask",
                                  Qt::QueuedConnection,
                                  Q_ARG(int, m_task->id()));

        delete m_task;
    }
}

With the current code, I really think we should give the ownership of the task to the RenderEngine.

As we discussed earlier, the code I wrote is not so good because the ImageResponse gets the ownership and then it gives that ownership away in a asymmetrical/strange/ugly way.

Supposed that we should try to make RenderEngine work properly with different threads, could we revert to the code I wrote earlier (RenderEngine takes ownership of the tasks, and we connect to it using a BlockingQueueConnection)?
It used to work with no issue when we tried it.

[Stefano Verzegnassi (verzegnassi-stefano)]

I had a further look at the issue.
It seems that QQuickPixmapCache calls QQuickImageResponse::cancel() several times when the LOK viewer is loaded.

We properly synchronize the threads when we queue/dequeue the task from the engine but, if the task is currently being processed, it gets deleted during its execution.

We need to ensure that the GUI thread (where RenderEngine lives) and the LOImageResponse are in sync when we delete the task.
I guess we'd be better not to give ownership of the task to a class that lives in another thread, and let RenderEngine handles its tasks at its best.

We only need to subscribe to the RenderEngine's signals, using a Qt::BlockingQueuedConnection.

Roman, I remember that the usage of a blocking connection was okay for you before you updated the RenderEngine.
What do you think?

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

249. By Stefano Verzegnassi on 2016-01-24

Moved all the RenderEngine code in LOPartsImageResponse to LOPartsImageProvider

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:249
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/93/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/450/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/93/rebuild

review: Needs Fixing (continuous-integration)

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

250. By Stefano Verzegnassi on 2016-01-24

Merged trunk. Updated translation template.

251. By Stefano Verzegnassi on 2016-01-24

Restored 'cache:false' so that we don't display a thumbnail from a different document

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:251
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/94/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/451/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/94/rebuild

review: Needs Fixing (continuous-integration)

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:251
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/100/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/475/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/100/rebuild

review: Needs Fixing (continuous-integration)

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

252. By Stefano Verzegnassi on 2016-01-26

Debugging Jenkins issue with QQuickAsyncImageProvider

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:252
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/101/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/476/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/101/rebuild

review: Needs Fixing (continuous-integration)

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:252
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/105/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/517/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/105/rebuild

review: Needs Fixing (continuous-integration)

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

253. By Stefano Verzegnassi on 2016-02-02

Merged trunk, updated .pot

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:253
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/108/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/518/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/108/rebuild

review: Needs Fixing (continuous-integration)

[Stefano Verzegnassi (verzegnassi-stefano)]

Still building the project against OTA-4 (May, 2014)...

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:253
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/167/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/519/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/167/rebuild

review: Needs Fixing (continuous-integration)

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

FAILED: Continuous integration, rev:253
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/209/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/526/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/docviewer-app-ci/209/rebuild

review: Needs Fixing (continuous-integration)

[Nicholas Skaggs (nskaggs)]

Text conflict in po/com.ubuntu.docviewer.pot
1 conflicts encountered.

Everytime something lands, you get this lovely conflict. Not sure if there's a better way for you to avoid this :-)

review: Needs Fixing

[Nicholas Skaggs (nskaggs)]

In other news, jenkins should build and run this cleanly now.

[Roman Shchekin (mrqtros)]

So, blockig connection solved all issues?
Just for inromation - you decided do not use render tasks separately from RenderEngine?

[Stefano Verzegnassi (verzegnassi-stefano)]

- So it seems. We've discussed about it some week ago, and it seems to keep everything in sync since it waits for the ImageResponse to complete its work on the returned image.

- I moved the code that calls the RenderEngine to the image provider. This way it is used from the GUI thread and there is no problem with ownership, etc...

[Roman Shchekin (mrqtros)]

Ok, let's merge then!

review: Approve

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

254. By Stefano Verzegnassi on 2016-02-05

Merged trunk + fixed .pot conflict

255. By Stefano Verzegnassi on 2016-02-05

Fixed LOK viewer going full-screen with a .odp/.ppt(x) document.
Both PDF full-screen presentation mode and LOK viewer were using a 'isPresentation' property with two different meaning. My fault, sorry! :/

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

PASSED: Continuous integration, rev:255
https://core-apps-jenkins.ubuntu.com/job/run-ap-tests-ci/1001/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/551/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/run-ap-tests-ci/1001/rebuild

review: Approve (continuous-integration)

[lp:~verzegnassi-stefano/ubuntu-docviewer-app/lok-qml-async-imageprovider]

256. By Stefano Verzegnassi on 2016-02-05

Removed Jenkins debug

[Jenkins Bot (ubuntu-core-apps-jenkins-bot)]

PASSED: Continuous integration, rev:256
https://core-apps-jenkins.ubuntu.com/job/run-ap-tests-ci/1002/
Executed test runs:
    None: https://core-apps-jenkins.ubuntu.com/job/generic-update-mp/552/console

Click here to trigger a rebuild:
https://core-apps-jenkins.ubuntu.com/job/run-ap-tests-ci/1002/rebuild

review: Approve (continuous-integration)

=== modified file 'po/com.ubuntu.docviewer.pot'
--- po/com.ubuntu.docviewer.pot	2016-02-03 13:51:11 +0000
+++ po/com.ubuntu.docviewer.pot	2016-02-05 22:57:36 +0000
@@ -8,7 +8,7 @@
 msgstr ""
 "Project-Id-Version: \n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2016-02-03 14:48+0100\n"
+"POT-Creation-Date: 2016-02-05 23:40+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <[e-mail]>\n"
@@ -216,7 +216,7 @@
 msgstr ""
 
 #: ../src/app/qml/documentPage/DocumentPage.qml:23
-#: /tmp/ubuntu-docviewer-app-build/po/com.ubuntu.docviewer.desktop.in.in.h:3
+#: /tmp/lok-qml-async-imageprovider-build/po/com.ubuntu.docviewer.desktop.in.in.h:3
 msgid "Documents"
 msgstr ""
 
@@ -367,21 +367,21 @@
 msgid "GO!"
 msgstr ""
 
-#: ../src/app/qml/loView/LOViewPage.qml:137
+#: ../src/app/qml/loView/LOViewPage.qml:167
 msgid "LibreOffice binaries not found."
 msgstr ""
 
-#: ../src/app/qml/loView/LOViewPage.qml:140
+#: ../src/app/qml/loView/LOViewPage.qml:170
 msgid "Error while loading LibreOffice."
 msgstr ""
 
-#: ../src/app/qml/loView/LOViewPage.qml:143
+#: ../src/app/qml/loView/LOViewPage.qml:173
 msgid ""
 "Document not loaded.\n"
 "The requested document may be corrupt or protected by a password."
 msgstr ""
 
-#: ../src/app/qml/loView/LOViewPage.qml:164
+#: ../src/app/qml/loView/LOViewPage.qml:228
 msgid "This sheet has no content."
 msgstr ""
 
@@ -446,7 +446,7 @@
 msgid "Choose a page between 1 and %1"
 msgstr ""
 
-#: ../src/app/qml/ubuntu-docviewer-app.qml:118
+#: ../src/app/qml/ubuntu-docviewer-app.qml:114
 msgid "File does not exist."
 msgstr ""
 
@@ -464,10 +464,10 @@
 msgid "copy %1"
 msgstr ""
 
-#: /tmp/ubuntu-docviewer-app-build/po/com.ubuntu.docviewer.desktop.in.in.h:1
+#: /tmp/lok-qml-async-imageprovider-build/po/com.ubuntu.docviewer.desktop.in.in.h:1
 msgid "Document Viewer"
 msgstr ""
 
-#: /tmp/ubuntu-docviewer-app-build/po/com.ubuntu.docviewer.desktop.in.in.h:2
+#: /tmp/lok-qml-async-imageprovider-build/po/com.ubuntu.docviewer.desktop.in.in.h:2
 msgid "documents;viewer;pdf;reader;"
 msgstr ""

=== modified file 'src/app/qml/loView/PartsView.qml'
--- src/app/qml/loView/PartsView.qml	2016-01-17 12:09:58 +0000
+++ src/app/qml/loView/PartsView.qml	2016-02-05 22:57:36 +0000
@@ -103,8 +103,8 @@
                         fillMode: Image.PreserveAspectFit
                         // Do not store a cache of the thumbnail, so that we don't show
                         // thumbnails of a previously loaded document.
-                        cache: true // TODO PLAY WITH IT
-                        source: model.thumbnail
+                        cache: false
+                        source: "image://lok/part/%1".arg(model.index)
                     }
                 }
 
@@ -172,8 +172,8 @@
                         fillMode: Image.PreserveAspectFit
                         // Do not store a cache of the thumbnail, so that we don't show
                         // thumbnails of a previously loaded document.
-                        cache: true // TODO PLAY WITH IT
-                        source: model.thumbnail
+                        cache: false
+                        source: "image://lok/part/%1".arg(model.index)
                     }
                 }
 

=== modified file 'src/app/qml/pdfView/PdfPresentation.qml'
--- src/app/qml/pdfView/PdfPresentation.qml	2016-01-23 12:34:25 +0000
+++ src/app/qml/pdfView/PdfPresentation.qml	2016-02-05 22:57:36 +0000
@@ -22,7 +22,7 @@
 Page {
     id: pdfPage
     property var poppler
-    property bool isPresentation: true
+    property bool isPresentationMode: true
     anchors.fill: parent
     title: DocumentViewer.getFileBaseNameFromPath(poppler.path)
     focus: true

=== modified file 'src/app/qml/ubuntu-docviewer-app.qml'
--- src/app/qml/ubuntu-docviewer-app.qml	2016-01-23 12:48:49 +0000
+++ src/app/qml/ubuntu-docviewer-app.qml	2016-02-05 22:57:36 +0000
@@ -34,7 +34,7 @@
     // force hiding Unity 8 indicators panel.
     property bool fullscreen: commandLineProxy.fullscreen ||
                               (!desktopMode && isLandscape && narrowWindow) ||
-                              pageStack.currentPage.hasOwnProperty("isPresentation")
+                              pageStack.currentPage.hasOwnProperty("isPresentationMode")
 
     readonly property bool desktopMode: DocumentViewer.desktopMode
 
@@ -200,5 +200,5 @@
 
     property bool nightModeEnabled: false
     layer.effect: NightModeShader {}
-    layer.enabled: nightModeEnabled && (pageStack.depth > 1) && !pageStack.currentPage.isPresentation
+    layer.enabled: nightModeEnabled && (pageStack.depth > 1) && !pageStack.currentPage.isPresentationMode
 }

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/CMakeLists.txt'
--- src/plugin/libreofficetoolkit-qml-plugin/CMakeLists.txt	2016-01-20 21:48:21 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/CMakeLists.txt	2016-02-05 22:57:36 +0000
@@ -23,6 +23,7 @@
     loview.cpp
     sgtileitem.cpp
     lopartsimageprovider.cpp
+    lopartsimageresponse.cpp
     lopartsmodel.cpp
     lorendertask.cpp
     ucunits.cpp

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lodocument.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/lodocument.cpp	2016-01-25 12:15:43 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lodocument.cpp	2016-02-05 22:57:36 +0000
@@ -170,7 +170,7 @@
     return result.rgbSwapped();
 }
 
-QImage LODocument::paintThumbnail(int part, qreal size)
+QImage LODocument::paintPart(int part, const QSize &size)
 {
     if (!m_lokDocument)
         return QImage();
@@ -189,11 +189,11 @@
     QSize resultSize;
 
     if (tWidth > tHeight) {
-        resultSize.setWidth(size);
-        resultSize.setHeight(size * tHeight / tWidth);
+        resultSize.setWidth(size.width());
+        resultSize.setHeight(size.width() * tHeight / tWidth);
     } else {
-        resultSize.setHeight(size);
-        resultSize.setWidth(size * tWidth / tHeight);
+        resultSize.setHeight(size.height());
+        resultSize.setWidth(size.height() * tWidth / tHeight);
     }
 
     QImage result = QImage(resultSize.width(), resultSize.height(), QImage::Format_RGB32);

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lodocument.h'
--- src/plugin/libreofficetoolkit-qml-plugin/lodocument.h	2016-01-25 12:59:02 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lodocument.h	2016-02-05 22:57:36 +0000
@@ -59,7 +59,7 @@
     QSize documentSize(int part) const;
 
     QImage paintTile(int part, const QSize& canvasSize, const QRect& tileSize, const qreal& zoom = 1.0);
-    QImage paintThumbnail(int part, qreal size);
+    QImage paintPart(int part, const QSize &size);
 
     int partsCount();
     QString getPartName(int index) const;

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.cpp	2015-12-12 10:06:55 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.cpp	2016-02-05 22:57:36 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015 Canonical, Ltd.
+ * Copyright (C) 2015 Stefano Verzegnassi
  *
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 3, as published
@@ -15,50 +15,42 @@
  */
 
 #include "lopartsimageprovider.h"
+#include "lopartsimageresponse.h"
+
 #include "lodocument.h"
+
 #include "../../app/renderengine.h"
+#include "lorendertask.h"
 
 LOPartsImageProvider::LOPartsImageProvider(const QSharedPointer<LODocument>& d)
-    : QQuickImageProvider(QQuickImageProvider::Image),
-      m_document(d)
+    : QQuickAsyncImageProvider()
+    , m_document(d)
 { }
 
-QImage LOPartsImageProvider::requestImage(const QString & id, QSize * size, const QSize & requestedSize)
+QQuickImageResponse *LOPartsImageProvider::requestImageResponse(const QString & id, const QSize & requestedSize)
 {
-    Q_UNUSED(size)
-
     QString type = id.section("/", 0, 0);
-
-    if (requestedSize.isNull() || type != "part" ||
-            m_document->documentType() != LODocument::PresentationDocument)
-        return QImage();
-
-    // Get info from "id".
-    int partNumber = id.section("/", 1, 1).toInt();
-    int itemId = id.section("/", 2, 2).toInt();
-
-    // Once rendered images can be found in hash.
-    if (m_images.contains(itemId))
-        return m_images[itemId];
-
-    const int defaultSize = 256;
-
-    RenderEngine::instance()->enqueueTask(createTask(partNumber, defaultSize, itemId));
-
-    // Return default image (empty).
-    static QImage defaultImage;
-    if (defaultImage.isNull())
-        defaultImage = QImage(defaultSize, defaultSize, QImage::Format_ARGB32);
-
-    return defaultImage;
+    int part = id.section("/", 1, 1).toInt();
+    bool isValid = bool(!requestedSize.isNull() || type == "part");
+
+    auto response = new LOPartsImageResponse(isValid);
+
+    if (isValid) {
+        int taskId = RenderEngine::getNextId();
+        response->setTaskId(taskId);
+        RenderEngine::instance()->enqueueTask(createTask(part, requestedSize, taskId));
+    }
+
+    return response;
 }
 
-ThumbnailRenderTask *LOPartsImageProvider::createTask(int part, qreal size, int id) const
+ThumbnailRenderTask* LOPartsImageProvider::createTask(int part, const QSize &size, int id) const
 {
     ThumbnailRenderTask* task = new ThumbnailRenderTask();
     task->setId(id);
     task->setPart(part);
     task->setDocument(m_document);
-    task->setSize(size);
+    task->setSize(size.isEmpty() ? QSize(256, 256) : size);
+
     return task;
 }

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.h'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.h	2015-12-12 10:06:55 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsimageprovider.h	2016-02-05 22:57:36 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015 Canonical, Ltd.
+ * Copyright (C) 2015 Stefano Verzegnassi
  *
  * This program is free software: you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 3, as published
@@ -18,28 +18,24 @@
 #ifndef LOPARTSIMAGEPROVIDER_H
 #define LOPARTSIMAGEPROVIDER_H
 
-#include <QQuickImageProvider>
+// For QQuickAsyncImageProvider
+#include <qquickimageprovider.h>
 #include <QSharedPointer>
-#include <QHash>
-#include <QDebug>
-
-#include "lorendertask.h"
 
 class LODocument;
+class ThumbnailRenderTask;
 
-class LOPartsImageProvider : public QQuickImageProvider
+class LOPartsImageProvider : public QQuickAsyncImageProvider
 {
 public:
     LOPartsImageProvider(const QSharedPointer<LODocument>& d);
-    QImage requestImage(const QString & id, QSize * size, const QSize & requestedSize);
+    QQuickImageResponse* requestImageResponse(const QString & id, const QSize & requestedSize);
 
-    QHash<int, QImage> m_images;
+private:
+    ThumbnailRenderTask* createTask(int part, const QSize &size, int id) const;
 
 private:
     QSharedPointer<LODocument> m_document;
-
-private:
-    ThumbnailRenderTask* createTask(int part, qreal size, int id) const;
 };
 
 #endif // LOPARTSIMAGEPROVIDER_H

=== added file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.cpp	1970-01-01 00:00:00 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.cpp	2016-02-05 22:57:36 +0000
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2015 Roman Shchekin
+ * Copyright (C) 2015 Stefano Verzegnassi
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "lopartsimageresponse.h"
+#include "lodocument.h"
+
+#include "../../app/renderengine.h"
+
+LOPartsImageResponse::LOPartsImageResponse(bool isRequestValid)
+    : m_taskId(0)
+{
+    if (!isRequestValid) {
+        m_errorString = "Requested size or id are not valid.";
+
+        QMetaObject::invokeMethod(this, "finished", Qt::QueuedConnection);
+        return;
+    }
+
+    connect(RenderEngine::instance(), &RenderEngine::taskRenderFinished,
+            this, [&](AbstractRenderTask *task, QImage img) {
+        if (m_taskId == task->id() && task->type() == RttImpressThumbnail) {
+            m_image = img;
+            Q_EMIT finished();
+        }
+    }, Qt::BlockingQueuedConnection);
+}
+
+LOPartsImageResponse::~LOPartsImageResponse()
+{
+    disconnect(this);
+
+    QMetaObject::invokeMethod(RenderEngine::instance(), "dequeueTask",
+                              Qt::QueuedConnection,
+                              Q_ARG(int, m_taskId));
+}
+
+QQuickTextureFactory * LOPartsImageResponse::textureFactory() const
+{
+    return QQuickTextureFactory::textureFactoryForImage(m_image);
+}

=== added file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.h'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.h	1970-01-01 00:00:00 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsimageresponse.h	2016-02-05 22:57:36 +0000
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2015 Stefano Verzegnassi
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef LOPARTSIMAGERESPONSE_H
+#define LOPARTSIMAGEPROVIDER_H
+
+// For QQuickImageResponse
+#include <qquickimageprovider.h>
+
+class LOPartsImageResponse : public QQuickImageResponse
+{
+public:
+    LOPartsImageResponse(bool isRequestValid);
+    ~LOPartsImageResponse();
+
+    void setTaskId(const int id) { m_taskId = id; }
+    QString errorString() const override { return m_errorString; }
+    QQuickTextureFactory * textureFactory() const override;
+
+private:
+    QString m_errorString;
+    QImage m_image;
+    int m_taskId;
+};
+
+
+#endif // LOPARTSIMAGERESPONSE_H

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.cpp	2015-10-11 11:31:22 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.cpp	2016-02-05 22:57:36 +0000
@@ -33,8 +33,6 @@
     QHash<int, QByteArray> roles;
     roles[IndexRole] = "index";
     roles[NameRole] = "name";
-    roles[IdRole] = "id";
-    roles[ThumbnailRole] = "thumbnail";
 
     return roles;
 }
@@ -57,10 +55,6 @@
         return part.index;
     case NameRole:
         return part.name;
-    case IdRole:
-        return part.id;
-    case ThumbnailRole:
-        return part.thumbnail;
 
     default:
         return 0;
@@ -79,22 +73,10 @@
     QVariantMap map;
     map["name"] = part.name;
     map["index"] = part.index;
-    map["id"] = part.id;
-    map["thumbnail"] = part.thumbnail;
 
     return map;
 }
 
-void LOPartsModel::notifyAboutChanges(int id)
-{
-    for (int i = 0; i < m_entries.size(); i++)
-        if (m_entries[i].id == id) {
-            m_entries[i].thumbnail += "/cached";
-            Q_EMIT dataChanged(createIndex(i, 0), createIndex(i + 1, 0));
-            break;
-        }
-}
-
 void LOPartsModel::fillModel() {
     if (!m_document)
         return;
@@ -112,8 +94,6 @@
 
         part.index = i;
         part.name = m_document->getPartName(i);
-        part.id = RenderEngine::getNextId();
-        part.thumbnail = QString("image://lok/part/%1/%2").arg(QString::number(part.index)).arg(QString::number(part.id));
 
         m_entries.append(part);
     }

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.h'
--- src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.h	2015-12-12 10:06:55 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lopartsmodel.h	2016-02-05 22:57:36 +0000
@@ -30,14 +30,11 @@
 {
 public:
     LOPartEntry():
-        id(0),
         index(0)
     { }
 
-    int id;
     int index;
     QString name;
-    QString thumbnail;
 };
 
 class LOPartsModel : public QAbstractListModel
@@ -50,8 +47,6 @@
     enum Roles {
         NameRole = Qt::UserRole + 1,
         IndexRole,
-        IdRole,
-        ThumbnailRole
     };
 
     explicit LOPartsModel(const QSharedPointer<LODocument>& document, QAbstractListModel *parent = 0);
@@ -64,8 +59,6 @@
 
     Q_INVOKABLE QVariantMap get(int index) const;
 
-    void notifyAboutChanges(int id);
-
 Q_SIGNALS:
     void countChanged();
 

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lorendertask.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/lorendertask.cpp	2016-01-07 11:23:50 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lorendertask.cpp	2016-02-05 22:57:36 +0000
@@ -21,5 +21,5 @@
 
 QImage ThumbnailRenderTask::doWork()
 {
-    return m_document->paintThumbnail(m_part, m_size);
+    return m_document->paintPart(m_part, m_size);
 }

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/lorendertask.h'
--- src/plugin/libreofficetoolkit-qml-plugin/lorendertask.h	2016-01-07 11:23:50 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/lorendertask.h	2016-02-05 22:57:36 +0000
@@ -48,10 +48,10 @@
     virtual RenderTaskType type() { return RttImpressThumbnail; }
     virtual QImage doWork();
 
-    qreal size() { return m_size; }
-    void setSize(qreal s) { m_size = s; }
+    QSize size() const { return m_size; }
+    void setSize(const QSize & s) { m_size = s; }
 protected:
-    qreal m_size;
+    QSize m_size;
 };
 
 #endif // LORENDERTASK_H

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/loview.cpp'
--- src/plugin/libreofficetoolkit-qml-plugin/loview.cpp	2016-01-29 12:12:54 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/loview.cpp	2016-02-05 22:57:36 +0000
@@ -344,9 +344,15 @@
 void LOView::slotTaskRenderFinished(AbstractRenderTask* task, QImage img)
 {
     if (task->type() == RttTile) {
-        updateTileData(task, img);
-    } else if (task->type() == RttImpressThumbnail) {
-        updateThumbnailModel(task, img);
+        int id = task->id();
+
+        for (auto i = m_tiles.begin(); i != m_tiles.end(); ++i) {
+            SGTileItem* sgtile = i.value();
+            if (sgtile->id() == id) {
+                sgtile->setData(img);
+                break;
+            }
+        }
     }
 }
 
@@ -401,25 +407,6 @@
     return task;
 }
 
-void LOView::updateTileData(AbstractRenderTask* task, QImage img)
-{
-    int id = task->id();
-    for (auto i = m_tiles.begin(); i != m_tiles.end(); ++i) {
-        SGTileItem* sgtile = i.value();
-        if (sgtile->id() == id) {
-            sgtile->setData(img);
-            break;
-        }
-    }
-}
-
-void LOView::updateThumbnailModel(AbstractRenderTask* task, QImage img)
-{
-    int id = task->id();
-    if (!m_imageProvider->m_images.contains(id))
-        m_imageProvider->m_images.insert(id, img);
-    m_partsModel->notifyAboutChanges(id);
-}
 
 void LOView::setError(const LibreOfficeError::Error &error)
 {

=== modified file 'src/plugin/libreofficetoolkit-qml-plugin/loview.h'
--- src/plugin/libreofficetoolkit-qml-plugin/loview.h	2016-01-21 00:29:15 +0000
+++ src/plugin/libreofficetoolkit-qml-plugin/loview.h	2016-02-05 22:57:36 +0000
@@ -113,8 +113,6 @@
     void createTile(int index, const QRect& rect);
     void clearView();
     TileRenderTask* createTask(const QRect& rect, int id) const;
-    void updateTileData(AbstractRenderTask* task, QImage img);
-    void updateThumbnailModel(AbstractRenderTask* task, QImage img);
 
     void setError(const LibreOfficeError::Error &error);
 };