Performance boost for previews that are already available in the cache: apply the...

[dolphin.git] / src / iconmanager.cpp

diff --git a/src/iconmanager.cpp b/src/iconmanager.cpp
index ae2b80b99bec5f2a90286b38597e0c481656abff..cde15b00b01757785fcdba1e4a3d91e00726725f 100644 (file)
--- a/src/iconmanager.cpp
+++ b/src/iconmanager.cpp
@@ -38,10 +38,12 @@ IconManager::IconManager(QAbstractItemView* parent, DolphinSortFilterProxyModel*
     QObject(parent),
     m_showPreview(false),
     m_view(parent),
+    m_previewTimer(0),
     m_previewJobs(),
     m_dolphinModel(0),
     m_proxyModel(model),
-    m_cutItemsCache()
+    m_cutItemsCache(),
+    m_previews()
 {
     Q_ASSERT(m_view->iconSize().isValid());  // each view must provide its current icon size
 
@@ -52,6 +54,9 @@ IconManager::IconManager(QAbstractItemView* parent, DolphinSortFilterProxyModel*
     QClipboard* clipboard = QApplication::clipboard();
     connect(clipboard, SIGNAL(dataChanged()),
             this, SLOT(updateCutItems()));
+
+    m_previewTimer = new QTimer(this);
+    connect(m_previewTimer, SIGNAL(timeout()), this, SLOT(dispatchPreviewQueue()));
 }
 
 IconManager::~IconManager()
@@ -98,49 +103,12 @@ void IconManager::updateIcons(const KFileItemList& items)
     }
 }
 
-void IconManager::replaceIcon(const KFileItem& item, const QPixmap& pixmap)
+void IconManager::addToPreviewQueue(const KFileItem& item, const QPixmap& pixmap)
 {
-    Q_ASSERT(!item.isNull());
-    if (!m_showPreview) {
-        // the preview has been canceled in the meantime
-        return;
-    }
-
-    // check whether the item is part of the directory lister (it is possible
-    // that a preview from an old directory lister is received)
-    KDirLister* dirLister = m_dolphinModel->dirLister();
-    bool isOldPreview = true;
-    const KUrl::List dirs = dirLister->directories();
-    const QString itemDir = item.url().directory();
-    foreach (KUrl url, dirs) {
-        if (url.path() == itemDir) {
-            isOldPreview = false;
-            break;
-        }
-    }
-    if (isOldPreview) {
-        return;
-    }
-
-    const QModelIndex idx = m_dolphinModel->indexForItem(item);
-    if (idx.isValid() && (idx.column() == 0)) {
-        QPixmap icon = pixmap;
-
-        const QString mimeType = item.mimetype();
-        const QString mimeTypeGroup = mimeType.left(mimeType.indexOf('/'));
-        if ((mimeTypeGroup != "image") || !applyImageFrame(icon)) {
-            limitToSize(icon, m_view->iconSize());
-        }
-
-        const QMimeData* mimeData = QApplication::clipboard()->mimeData();
-        if (KonqMimeData::decodeIsCutSelection(mimeData) && isCutItem(item)) {
-            KIconEffect iconEffect;
-            icon = iconEffect.apply(icon, KIconLoader::Desktop, KIconLoader::DisabledState);
-            m_dolphinModel->setData(idx, QIcon(icon), Qt::DecorationRole);
-        } else {
-            m_dolphinModel->setData(idx, QIcon(icon), Qt::DecorationRole);
-        }
-    }
+    Preview preview;
+    preview.item = item;
+    preview.pixmap = pixmap;
+    m_previews.append(preview);
 }
 
 void IconManager::slotPreviewJobFinished(KJob* job)
@@ -165,6 +133,37 @@ void IconManager::updateCutItems()
     applyCutItemEffect();
 }
 
+void IconManager::dispatchPreviewQueue()
+{
+    const int previewsCount = m_previews.count();
+    if (previewsCount == 0) {
+        return;
+    }
+
+    // Applying the previews to the model must be done step by step
+    // in larger blocks: Applying a preview immediately when getting the signal
+    // 'gotPreview()' from the PreviewJob is too expensive, as a relayout
+    // of the view would be triggered for each single preview.
+
+    int dispatchCount = 30;
+    if (dispatchCount > previewsCount) {
+        dispatchCount = previewsCount;
+    }
+
+    for (int i = 0; i < dispatchCount; ++i) {
+        const Preview& preview = m_previews.first();
+        replaceIcon(preview.item, preview.pixmap);
+        m_previews.pop_front();
+    }
+
+    if (m_previews.count() > 0) {
+        // there are still pending previews; if no preview job is
+        // working, poll more aggressively:
+        const int timeout = (m_previewJobs.count() > 0) ? 200 : 10;
+        m_previewTimer->start(timeout);
+    }
+}
+
 void IconManager::generatePreviews(const KFileItemList &items)
 {
     Q_ASSERT(m_showPreview);
@@ -187,11 +186,57 @@ void IconManager::generatePreviews(const KFileItemList &items)
     const QSize size = m_view->iconSize();
     KIO::PreviewJob* job = KIO::filePreview(orderedItems, 128, 128);
     connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
-            this, SLOT(replaceIcon(const KFileItem&, const QPixmap&)));
+            this, SLOT(addToPreviewQueue(const KFileItem&, const QPixmap&)));
     connect(job, SIGNAL(finished(KJob*)),
             this, SLOT(slotPreviewJobFinished(KJob*)));
 
     m_previewJobs.append(job);
+    m_previewTimer->start(200);
+}
+
+void IconManager::replaceIcon(const KFileItem& item, const QPixmap& pixmap)
+{
+    Q_ASSERT(!item.isNull());
+    if (!m_showPreview) {
+        // the preview has been canceled in the meantime
+        return;
+    }
+
+    // check whether the item is part of the directory lister (it is possible
+    // that a preview from an old directory lister is received)
+    KDirLister* dirLister = m_dolphinModel->dirLister();
+    bool isOldPreview = true;
+    const KUrl::List dirs = dirLister->directories();
+    const QString itemDir = item.url().directory();
+    foreach (KUrl url, dirs) {
+        if (url.path() == itemDir) {
+            isOldPreview = false;
+            break;
+        }
+    }
+    if (isOldPreview) {
+        return;
+    }
+
+    const QModelIndex idx = m_dolphinModel->indexForItem(item);
+    if (idx.isValid() && (idx.column() == 0)) {
+        QPixmap icon = pixmap;
+
+        const QString mimeType = item.mimetype();
+        const QString mimeTypeGroup = mimeType.left(mimeType.indexOf('/'));
+        if ((mimeTypeGroup != "image") || !applyImageFrame(icon)) {
+            limitToSize(icon, m_view->iconSize());
+        }
+
+        const QMimeData* mimeData = QApplication::clipboard()->mimeData();
+        if (KonqMimeData::decodeIsCutSelection(mimeData) && isCutItem(item)) {
+            KIconEffect iconEffect;
+            icon = iconEffect.apply(icon, KIconLoader::Desktop, KIconLoader::DisabledState);
+            m_dolphinModel->setData(idx, QIcon(icon), Qt::DecorationRole);
+        } else {
+            m_dolphinModel->setData(idx, QIcon(icon), Qt::DecorationRole);
+        }
+    }
 }
 
 bool IconManager::isCutItem(const KFileItem& item) const
@@ -285,8 +330,8 @@ bool IconManager::applyImageFrame(QPixmap& icon)
     painter.drawRect(0, 0, width, height);
     painter.drawRect(1, 1, width - 2, height - 2);
 
-    // dimm image frame by 25 %
-    painter.setPen(QColor(0, 0, 0, 64));
+    // dim image frame by 12.5 %
+    painter.setPen(QColor(0, 0, 0, 32));
     painter.drawRect(frame, frame, width - doubleFrame, height - doubleFrame);
     painter.end();