1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
/*
* Copyright (C) 2014 Apple Inc. All rights reserved.
* Copyright (c) 2010, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
* OWNER OR 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 "ScrollAnimator.h"
#include "FloatPoint.h"
#include "PlatformWheelEvent.h"
#include "ScrollableArea.h"
#include <algorithm>
#include <wtf/PassOwnPtr.h>
namespace WebCore {
#if !ENABLE(SMOOTH_SCROLLING) && !PLATFORM(IOS)
PassOwnPtr<ScrollAnimator> ScrollAnimator::create(ScrollableArea* scrollableArea)
{
return adoptPtr(new ScrollAnimator(scrollableArea));
}
#endif
ScrollAnimator::ScrollAnimator(ScrollableArea* scrollableArea)
: m_scrollableArea(scrollableArea)
, m_currentPosX(0)
, m_currentPosY(0)
{
}
ScrollAnimator::~ScrollAnimator()
{
}
bool ScrollAnimator::scroll(ScrollbarOrientation orientation, ScrollGranularity, float step, float multiplier)
{
float* currentPos = (orientation == HorizontalScrollbar) ? &m_currentPosX : &m_currentPosY;
float newPos = std::max(std::min(*currentPos + (step * multiplier), static_cast<float>(m_scrollableArea->scrollSize(orientation))), 0.0f);
float delta = *currentPos - newPos;
if (*currentPos == newPos)
return false;
*currentPos = newPos;
notifyPositionChanged(orientation == HorizontalScrollbar ? FloatSize(delta, 0) : FloatSize(0, delta));
return true;
}
void ScrollAnimator::scrollToOffsetWithoutAnimation(const FloatPoint& offset)
{
FloatSize delta = FloatSize(offset.x() - m_currentPosX, offset.y() - m_currentPosY);
m_currentPosX = offset.x();
m_currentPosY = offset.y();
notifyPositionChanged(delta);
}
bool ScrollAnimator::handleWheelEvent(const PlatformWheelEvent& e)
{
#if PLATFORM(COCOA)
// Events in the PlatformWheelEventPhaseMayBegin phase have no deltas, and therefore never passes through the scroll handling logic below.
// This causes us to return with an 'unhandled' return state, even though this event was successfully processed.
//
// We receive at least one PlatformWheelEventPhaseMayBegin when starting main-thread scrolling (see FrameView::wheelEvent), which can
// fool the scrolling thread into attempting to handle the scroll, unless we treat the event as handled here.
if (e.phase() == PlatformWheelEventPhaseMayBegin)
return true;
#endif
Scrollbar* horizontalScrollbar = m_scrollableArea->horizontalScrollbar();
Scrollbar* verticalScrollbar = m_scrollableArea->verticalScrollbar();
// Accept the event if we have a scrollbar in that direction and can still
// scroll any further.
float deltaX = horizontalScrollbar ? e.deltaX() : 0;
float deltaY = verticalScrollbar ? e.deltaY() : 0;
bool handled = false;
ScrollGranularity granularity = ScrollByPixel;
IntSize maxForwardScrollDelta = m_scrollableArea->maximumScrollPosition() - m_scrollableArea->scrollPosition();
IntSize maxBackwardScrollDelta = m_scrollableArea->scrollPosition() - m_scrollableArea->minimumScrollPosition();
if ((deltaX < 0 && maxForwardScrollDelta.width() > 0)
|| (deltaX > 0 && maxBackwardScrollDelta.width() > 0)
|| (deltaY < 0 && maxForwardScrollDelta.height() > 0)
|| (deltaY > 0 && maxBackwardScrollDelta.height() > 0)) {
handled = true;
if (deltaY) {
if (e.granularity() == ScrollByPageWheelEvent) {
bool negative = deltaY < 0;
deltaY = Scrollbar::pageStepDelta(m_scrollableArea->visibleHeight());
if (negative)
deltaY = -deltaY;
}
scroll(VerticalScrollbar, granularity, verticalScrollbar->pixelStep(), -deltaY);
}
if (deltaX) {
if (e.granularity() == ScrollByPageWheelEvent) {
bool negative = deltaX < 0;
deltaX = Scrollbar::pageStepDelta(m_scrollableArea->visibleWidth());
if (negative)
deltaX = -deltaX;
}
scroll(HorizontalScrollbar, granularity, horizontalScrollbar->pixelStep(), -deltaX);
}
}
return handled;
}
#if ENABLE(TOUCH_EVENTS)
bool ScrollAnimator::handleTouchEvent(const PlatformTouchEvent&)
{
return false;
}
#endif
void ScrollAnimator::setCurrentPosition(const FloatPoint& position)
{
m_currentPosX = position.x();
m_currentPosY = position.y();
}
FloatPoint ScrollAnimator::currentPosition() const
{
return FloatPoint(m_currentPosX, m_currentPosY);
}
void ScrollAnimator::notifyPositionChanged(const FloatSize& delta)
{
UNUSED_PARAM(delta);
m_scrollableArea->setScrollOffsetFromAnimation(IntPoint(m_currentPosX, m_currentPosY));
}
} // namespace WebCore
|
