1/* 2 * Copyright (C) 2014 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27 28#include "WheelEventDeltaTracker.h" 29 30#include "PlatformWheelEvent.h" 31 32namespace WebCore { 33 34WheelEventDeltaTracker::WheelEventDeltaTracker() 35 : m_isTrackingDeltas(false) 36{ 37} 38 39WheelEventDeltaTracker::~WheelEventDeltaTracker() 40{ 41} 42 43void WheelEventDeltaTracker::beginTrackingDeltas() 44{ 45 m_recentWheelEventDeltas.clear(); 46 m_isTrackingDeltas = true; 47} 48 49void WheelEventDeltaTracker::endTrackingDeltas() 50{ 51 m_isTrackingDeltas = false; 52} 53 54void WheelEventDeltaTracker::recordWheelEventDelta(const PlatformWheelEvent& event) 55{ 56 m_recentWheelEventDeltas.append(FloatSize(event.deltaX(), event.deltaY())); 57 if (m_recentWheelEventDeltas.size() > recentEventCount) 58 m_recentWheelEventDeltas.removeFirst(); 59} 60 61static bool deltaIsPredominantlyVertical(const FloatSize& delta) 62{ 63 return fabs(delta.height()) > fabs(delta.width()); 64} 65 66DominantScrollGestureDirection WheelEventDeltaTracker::dominantScrollGestureDirection() const 67{ 68 bool allVertical = m_recentWheelEventDeltas.size(); 69 bool allHorizontal = m_recentWheelEventDeltas.size(); 70 71 for (const auto& delta : m_recentWheelEventDeltas) { 72 bool isVertical = deltaIsPredominantlyVertical(delta); 73 allVertical &= isVertical; 74 allHorizontal &= !isVertical; 75 } 76 77 if (allVertical) 78 return DominantScrollGestureDirection::Vertical; 79 80 if (allHorizontal) 81 return DominantScrollGestureDirection::Horizontal; 82 83 return DominantScrollGestureDirection::None; 84} 85 86} // namespace WebCore 87