1 | /* |
2 | * Copyright (C) 2015-2016 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 | #include "WheelEventDeltaFilter.h" |
28 | |
29 | #include "FloatSize.h" |
30 | #include "Logging.h" |
31 | #include <wtf/text/TextStream.h> |
32 | |
33 | #if PLATFORM(MAC) |
34 | #include "WheelEventDeltaFilterMac.h" |
35 | #endif |
36 | |
37 | namespace WebCore { |
38 | |
39 | WheelEventDeltaFilter::WheelEventDeltaFilter() = default; |
40 | |
41 | WheelEventDeltaFilter::~WheelEventDeltaFilter() = default; |
42 | |
43 | std::unique_ptr<WheelEventDeltaFilter> WheelEventDeltaFilter::create() |
44 | { |
45 | #if PLATFORM(MAC) |
46 | return std::make_unique<WheelEventDeltaFilterMac>(); |
47 | #else |
48 | return std::make_unique<BasicWheelEventDeltaFilter>(); |
49 | #endif |
50 | } |
51 | |
52 | bool WheelEventDeltaFilter::isFilteringDeltas() const |
53 | { |
54 | return m_isFilteringDeltas; |
55 | } |
56 | |
57 | FloatSize WheelEventDeltaFilter::filteredDelta() const |
58 | { |
59 | return m_currentFilteredDelta; |
60 | } |
61 | |
62 | FloatSize WheelEventDeltaFilter::filteredVelocity() const |
63 | { |
64 | return m_currentFilteredVelocity; |
65 | } |
66 | |
67 | BasicWheelEventDeltaFilter::BasicWheelEventDeltaFilter() |
68 | : WheelEventDeltaFilter() |
69 | { |
70 | } |
71 | |
72 | const size_t basicWheelEventDeltaFilterWindowSize = 3; |
73 | |
74 | void BasicWheelEventDeltaFilter::updateFromDelta(const FloatSize& delta) |
75 | { |
76 | m_currentFilteredDelta = delta; |
77 | if (!m_isFilteringDeltas) |
78 | return; |
79 | |
80 | m_recentWheelEventDeltas.append(delta); |
81 | if (m_recentWheelEventDeltas.size() > basicWheelEventDeltaFilterWindowSize) |
82 | m_recentWheelEventDeltas.removeFirst(); |
83 | |
84 | DominantScrollGestureDirection scrollDirection = dominantScrollGestureDirection(); |
85 | if (scrollDirection == DominantScrollGestureDirection::Vertical) |
86 | m_currentFilteredDelta.setWidth(0); |
87 | else if (scrollDirection == DominantScrollGestureDirection::Horizontal) |
88 | m_currentFilteredDelta.setHeight(0); |
89 | } |
90 | |
91 | void BasicWheelEventDeltaFilter::beginFilteringDeltas() |
92 | { |
93 | m_recentWheelEventDeltas.clear(); |
94 | m_isFilteringDeltas = true; |
95 | } |
96 | |
97 | void BasicWheelEventDeltaFilter::endFilteringDeltas() |
98 | { |
99 | m_currentFilteredDelta = FloatSize(0, 0); |
100 | m_isFilteringDeltas = false; |
101 | } |
102 | |
103 | static inline bool deltaIsPredominantlyVertical(const FloatSize& delta) |
104 | { |
105 | return fabs(delta.height()) > fabs(delta.width()); |
106 | } |
107 | |
108 | DominantScrollGestureDirection BasicWheelEventDeltaFilter::dominantScrollGestureDirection() const |
109 | { |
110 | bool allVertical = m_recentWheelEventDeltas.size(); |
111 | bool allHorizontal = m_recentWheelEventDeltas.size(); |
112 | |
113 | for (const auto& delta : m_recentWheelEventDeltas) { |
114 | bool isVertical = deltaIsPredominantlyVertical(delta); |
115 | allVertical &= isVertical; |
116 | allHorizontal &= !isVertical; |
117 | } |
118 | |
119 | if (allVertical) |
120 | return DominantScrollGestureDirection::Vertical; |
121 | |
122 | if (allHorizontal) |
123 | return DominantScrollGestureDirection::Horizontal; |
124 | |
125 | return DominantScrollGestureDirection::None; |
126 | } |
127 | |
128 | }; |
129 | |