1 files changed, 104 insertions, 0 deletions
diff --git a/Source/WebKit2/UIProcess/qt/QtPanGestureRecognizer.cpp b/Source/WebKit2/UIProcess/qt/QtPanGestureRecognizer.cpp
new file mode 100644
index 000000000..6f93c9391
--- /dev/null
+++ b/Source/WebKit2/UIProcess/qt/QtPanGestureRecognizer.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2011 Benjamin Poulain <benjamin@webkit.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "config.h"
+
+#include "QtPanGestureRecognizer.h"
+
+#include "QtWebPageEventHandler.h"
+#include <QTouchEvent>
+
+namespace WebKit {
+
+QtPanGestureRecognizer::QtPanGestureRecognizer(QtWebPageEventHandler* eventHandler)
+    : QtGestureRecognizer(eventHandler)
+{
+    reset();
+}
+
+bool QtPanGestureRecognizer::recognize(const QTouchEvent* event, qint64 eventTimestampMillis)
+{
+    if (!interactionEngine())
+        return false;
+
+    // Pan gesture always starts on TouchBegin unless the engine is suspended, or
+    // we ignored the event.
+    if (m_state == NoGesture && event->type() != QEvent::TouchBegin)
+        return false;
+
+    // Having multiple touch points cancel the panning gesture.
+    if (event->touchPoints().size() > 1) {
+        if (m_state == GestureRecognized)
+            interactionEngine()->panGestureCancelled();
+        reset();
+        return false;
+    }
+
+    const QTouchEvent::TouchPoint& touchPoint = event->touchPoints().first();
+
+    switch (event->type()) {
+    case QEvent::TouchBegin:
+        ASSERT(m_state == NoGesture);
+        m_state = GestureRecognitionStarted;
+        m_firstPosition = touchPoint.screenPos();
+        return false;
+    case QEvent::TouchUpdate: {
+        ASSERT(m_state != NoGesture);
+        if (m_state == GestureRecognitionStarted) {
+            // To start the gesture, the delta from start in screen coordinates
+            // must be bigger than the trigger threshold.
+            QPointF totalOffsetFromStart(touchPoint.screenPos() - m_firstPosition);
+            if (qAbs(totalOffsetFromStart.x()) < panningInitialTriggerDistanceThreshold && qAbs(totalOffsetFromStart.y()) < panningInitialTriggerDistanceThreshold)
+                return false;
+
+            m_state = GestureRecognized;
+            interactionEngine()->panGestureStarted(touchPoint.pos(), eventTimestampMillis);
+        }
+
+        ASSERT(m_state == GestureRecognized);
+        interactionEngine()->panGestureRequestUpdate(touchPoint.pos(), eventTimestampMillis);
+        return true;
+    }
+    case QEvent::TouchEnd:
+        if (m_state == GestureRecognized) {
+            interactionEngine()->panGestureEnded(touchPoint.pos(), eventTimestampMillis);
+            reset();
+            return true;
+        }
+        ASSERT(m_state == GestureRecognitionStarted);
+        reset();
+        return false;
+    default:
+        ASSERT_NOT_REACHED();
+    }
+    return false;
+}
+
+void QtPanGestureRecognizer::reset()
+{
+    QtGestureRecognizer::reset();
+    m_firstPosition = QPointF();
+}
+
+} // namespace WebKit