1/*
2 * Copyright (C) 2004, 2005, 2006, 2009 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 COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef PlatformWheelEvent_h
27#define PlatformWheelEvent_h
28
29#include "platform/PlatformEvent.h"
30#include "platform/geometry/IntPoint.h"
31
32namespace blink {
33
34// Wheel events come in two flavors:
35// The ScrollByPixelWheelEvent is a fine-grained event that specifies the precise number of pixels to scroll. It is sent directly by MacBook touchpads on OS X,
36// and synthesized in other cases where platforms generate line-by-line scrolling events.
37// The ScrollByPageWheelEvent indicates that the wheel event should scroll an entire page. In this case WebCore's built in paging behavior is used to page
38// up and down (you get the same behavior as if the user was clicking in a scrollbar track to page up or page down).
39enum PlatformWheelEventGranularity {
40    ScrollByPageWheelEvent,
41    ScrollByPixelWheelEvent,
42};
43
44#if OS(MACOSX)
45enum PlatformWheelEventPhase {
46    PlatformWheelEventPhaseNone        = 0,
47    PlatformWheelEventPhaseBegan       = 1 << 0,
48    PlatformWheelEventPhaseStationary  = 1 << 1,
49    PlatformWheelEventPhaseChanged     = 1 << 2,
50    PlatformWheelEventPhaseEnded       = 1 << 3,
51    PlatformWheelEventPhaseCancelled   = 1 << 4,
52    PlatformWheelEventPhaseMayBegin    = 1 << 5,
53};
54#endif
55
56class PlatformWheelEvent : public PlatformEvent {
57public:
58    PlatformWheelEvent()
59        : PlatformEvent(PlatformEvent::Wheel)
60        , m_deltaX(0)
61        , m_deltaY(0)
62        , m_wheelTicksX(0)
63        , m_wheelTicksY(0)
64        , m_granularity(ScrollByPixelWheelEvent)
65        , m_hasPreciseScrollingDeltas(false)
66#if OS(MACOSX)
67        , m_phase(PlatformWheelEventPhaseNone)
68        , m_momentumPhase(PlatformWheelEventPhaseNone)
69        , m_scrollCount(0)
70        , m_unacceleratedScrollingDeltaX(0)
71        , m_unacceleratedScrollingDeltaY(0)
72        , m_canRubberbandLeft(true)
73        , m_canRubberbandRight(true)
74#endif
75    {
76    }
77
78    PlatformWheelEvent(IntPoint position, IntPoint globalPosition, float deltaX, float deltaY, float wheelTicksX, float wheelTicksY, PlatformWheelEventGranularity granularity, bool shiftKey, bool ctrlKey, bool altKey, bool metaKey)
79        : PlatformEvent(PlatformEvent::Wheel, shiftKey, ctrlKey, altKey, metaKey, 0)
80        , m_position(position)
81        , m_globalPosition(globalPosition)
82        , m_deltaX(deltaX)
83        , m_deltaY(deltaY)
84        , m_wheelTicksX(wheelTicksX)
85        , m_wheelTicksY(wheelTicksY)
86        , m_granularity(granularity)
87        , m_hasPreciseScrollingDeltas(false)
88#if OS(MACOSX)
89        , m_phase(PlatformWheelEventPhaseNone)
90        , m_momentumPhase(PlatformWheelEventPhaseNone)
91        , m_scrollCount(0)
92        , m_unacceleratedScrollingDeltaX(0)
93        , m_unacceleratedScrollingDeltaY(0)
94        , m_canRubberbandLeft(true)
95        , m_canRubberbandRight(true)
96#endif
97    {
98    }
99
100    const IntPoint& position() const { return m_position; } // PlatformWindow coordinates.
101    const IntPoint& globalPosition() const { return m_globalPosition; } // Screen coordinates.
102
103    float deltaX() const { return m_deltaX; }
104    float deltaY() const { return m_deltaY; }
105
106    float wheelTicksX() const { return m_wheelTicksX; }
107    float wheelTicksY() const { return m_wheelTicksY; }
108
109    PlatformWheelEventGranularity granularity() const { return m_granularity; }
110
111    bool hasPreciseScrollingDeltas() const { return m_hasPreciseScrollingDeltas; }
112    void setHasPreciseScrollingDeltas(bool b) { m_hasPreciseScrollingDeltas = b; }
113#if OS(MACOSX)
114    PlatformWheelEventPhase phase() const { return m_phase; }
115    PlatformWheelEventPhase momentumPhase() const { return m_momentumPhase; }
116    unsigned scrollCount() const { return m_scrollCount; }
117    float unacceleratedScrollingDeltaX() const { return m_unacceleratedScrollingDeltaX; }
118    float unacceleratedScrollingDeltaY() const { return m_unacceleratedScrollingDeltaY; }
119    bool useLatchedEventNode() const { return m_momentumPhase == PlatformWheelEventPhaseBegan || m_momentumPhase == PlatformWheelEventPhaseChanged; }
120    bool canRubberbandLeft() const { return m_canRubberbandLeft; }
121    bool canRubberbandRight() const { return m_canRubberbandRight; }
122#else
123    bool useLatchedEventNode() const { return false; }
124#endif
125
126protected:
127    IntPoint m_position;
128    IntPoint m_globalPosition;
129    float m_deltaX;
130    float m_deltaY;
131    float m_wheelTicksX;
132    float m_wheelTicksY;
133    PlatformWheelEventGranularity m_granularity;
134    bool m_hasPreciseScrollingDeltas;
135#if OS(MACOSX)
136    PlatformWheelEventPhase m_phase;
137    PlatformWheelEventPhase m_momentumPhase;
138    unsigned m_scrollCount;
139    float m_unacceleratedScrollingDeltaX;
140    float m_unacceleratedScrollingDeltaY;
141    bool m_canRubberbandLeft;
142    bool m_canRubberbandRight;
143#endif
144};
145
146} // namespace blink
147
148#endif // PlatformWheelEvent_h
149