Sourcecode hierarchy cleanup: Move class PixmapViewer from "src" to "src/panels/information"

svn path=/trunk/KDE/kdebase/apps/; revision=1154154

2 files changed, 228 insertions, 0 deletions

diff --git a/src/panels/information/pixmapviewer.cpp b/src/panels/information/pixmapviewer.cpp
new file mode 100644
index 000000000..416e53f1f
--- /dev/null
+++ b/src/panels/information/pixmapviewer.cpp
@@ -0,0 +1,130 @@
+/***************************************************************************
+ *   Copyright (C) 2006 by Peter Penz <[email protected]>                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY 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, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
+ ***************************************************************************/
+
+#include "pixmapviewer.h"
+
+#include <kiconloader.h>
+
+#include <QLayout>
+#include <QPainter>
+#include <QPixmap>
+#include <QKeyEvent>
+
+PixmapViewer::PixmapViewer(QWidget* parent, Transition transition) :
+    QWidget(parent),
+    m_transition(transition),
+    m_animationStep(0),
+    m_sizeHint()
+{
+    setMinimumWidth(KIconLoader::SizeEnormous);
+    setMinimumHeight(KIconLoader::SizeEnormous);
+
+    m_animation.setDuration(150);
+    m_animation.setCurveShape(QTimeLine::LinearCurve);
+
+    if (m_transition != NoTransition) {
+        connect(&m_animation, SIGNAL(valueChanged(qreal)), this, SLOT(update()));
+        connect(&m_animation, SIGNAL(finished()), this, SLOT(checkPendingPixmaps()));
+    }
+}
+
+PixmapViewer::~PixmapViewer()
+{
+}
+
+void PixmapViewer::setPixmap(const QPixmap& pixmap)
+{
+    if (pixmap.isNull()) {
+        return;
+    }
+
+    if ((m_transition != NoTransition) && (m_animation.state() == QTimeLine::Running)) {
+        m_pendingPixmaps.enqueue(pixmap);
+        if (m_pendingPixmaps.count() > 5) {
+            // don't queue more than 5 pixmaps
+            m_pendingPixmaps.takeFirst();
+        }
+        return;
+    }
+
+    m_oldPixmap = m_pixmap.isNull() ? pixmap : m_pixmap;
+    m_pixmap = pixmap;
+    update();
+
+    const bool animate = (m_transition != NoTransition) &&
+                         (m_pixmap.size() != m_oldPixmap.size());
+    if (animate) {
+        m_animation.start();
+    }
+}
+
+void PixmapViewer::setSizeHint(const QSize& size)
+{
+    m_sizeHint = size;
+    updateGeometry();
+}
+
+QSize PixmapViewer::sizeHint() const
+{
+    return m_sizeHint;
+}
+
+void PixmapViewer::paintEvent(QPaintEvent* event)
+{
+    QWidget::paintEvent(event);
+
+    QPainter painter(this);
+
+    if (m_transition != NoTransition) {
+        const float value = m_animation.currentValue();
+        const int scaledWidth  = static_cast<int>((m_oldPixmap.width()  * (1.0 - value)) + (m_pixmap.width()  * value));
+        const int scaledHeight = static_cast<int>((m_oldPixmap.height() * (1.0 - value)) + (m_pixmap.height() * value));
+
+        const int x = (width()  - scaledWidth ) / 2;
+        const int y = (height() - scaledHeight) / 2;
+
+        const bool useOldPixmap = (m_transition == SizeTransition) &&
+                                  (m_oldPixmap.width() > m_pixmap.width());
+        const QPixmap& largePixmap = useOldPixmap ? m_oldPixmap : m_pixmap;
+        const QPixmap scaledPixmap = largePixmap.scaled(scaledWidth,
+                                                        scaledHeight,
+                                                        Qt::IgnoreAspectRatio,
+                                                        Qt::FastTransformation);
+        painter.drawPixmap(x, y, scaledPixmap);
+    } else {
+        const int x = (width()  - m_pixmap.width() ) / 2;
+        const int y = (height() - m_pixmap.height()) / 2;
+        painter.drawPixmap(x, y, m_pixmap);
+    }
+}
+
+void PixmapViewer::checkPendingPixmaps()
+{
+    if (m_pendingPixmaps.count() > 0) {
+        QPixmap pixmap = m_pendingPixmaps.dequeue();
+        m_oldPixmap = m_pixmap.isNull() ? pixmap : m_pixmap;
+        m_pixmap = pixmap;
+        update();
+        m_animation.start();
+    } else {
+        m_oldPixmap = m_pixmap;
+    }
+}
+
+#include "pixmapviewer.moc"
diff --git a/src/panels/information/pixmapviewer.h b/src/panels/information/pixmapviewer.h
new file mode 100644
index 000000000..c15750bb7
--- /dev/null
+++ b/src/panels/information/pixmapviewer.h
@@ -0,0 +1,98 @@
+/***************************************************************************
+ *   Copyright (C) 2006 by Peter Penz <[email protected]>                  *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY 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, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
+ ***************************************************************************/
+
+#ifndef PIXMAPVIEWER_H
+#define PIXMAPVIEWER_H
+
+#include <QWidget>
+#include <QPixmap>
+#include <QQueue>
+#include <QTimeLine>
+
+class QPaintEvent;
+
+/**
+ * @brief Widget which shows a pixmap centered inside the boundaries.
+ *
+ * When the pixmap is changed, a smooth transition is done from the old pixmap
+ * to the new pixmap.
+ */
+class PixmapViewer : public QWidget
+{
+    Q_OBJECT
+
+public:
+    enum Transition
+    {
+        /** No transition is done when the pixmap is changed. */
+        NoTransition,
+
+        /**
+         * The old pixmap is replaced by the new pixmap and the size is
+         * adjusted smoothly to the size of the new pixmap.
+         */
+        DefaultTransition,
+
+        /**
+         * If the old pixmap and the new pixmap have the same content, but
+         * a different size it is recommended to use Transition::SizeTransition
+         * instead of Transition::DefaultTransition. In this case it is assured
+         * that the larger pixmap is used for downscaling, which leads
+         * to an improved scaling output.
+         */
+        SizeTransition
+    };
+
+    explicit PixmapViewer(QWidget* parent,
+                          Transition transition = DefaultTransition);
+
+    virtual ~PixmapViewer();
+    void setPixmap(const QPixmap& pixmap);
+    QPixmap pixmap() const;
+
+    /**
+     * Sets the size hint to \a size and triggers a relayout
+     * of the parent widget. Per default no size hint is given.
+     */
+    void setSizeHint(const QSize& size);
+    virtual QSize sizeHint() const;
+
+protected:
+    virtual void paintEvent(QPaintEvent* event);
+
+private Q_SLOTS:
+    void checkPendingPixmaps();
+
+private:
+    QPixmap m_pixmap;
+    QPixmap m_oldPixmap;
+    QQueue<QPixmap> m_pendingPixmaps;
+    QTimeLine m_animation;
+    Transition m_transition;
+    int m_animationStep;
+    QSize m_sizeHint;
+};
+
+inline QPixmap PixmapViewer::pixmap() const
+{
+    return m_pixmap;
+}
+
+
+#endif