1 /*
2 * Copyright (C) 2006, 2007 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 #include "config.h"
27 #include "PlatformWheelEvent.h"
28
29 #include "FloatPoint.h"
30 #include "FloatSize.h"
31 #include <windows.h>
32 #include <windowsx.h>
33
34 namespace WebCore {
35
36 #define HIGH_BIT_MASK_SHORT 0x8000
37 #define SPI_GETWHEELSCROLLCHARS 0x006C
38
positionForEvent(HWND hWnd,LPARAM lParam)39 static IntPoint positionForEvent(HWND hWnd, LPARAM lParam)
40 {
41 POINT point = {GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
42 ScreenToClient(hWnd, &point);
43 return point;
44 }
45
globalPositionForEvent(HWND hWnd,LPARAM lParam)46 static IntPoint globalPositionForEvent(HWND hWnd, LPARAM lParam)
47 {
48 POINT point = {GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
49 return point;
50 }
51
horizontalScrollChars()52 static int horizontalScrollChars()
53 {
54 static ULONG scrollChars;
55 if (!scrollChars && !SystemParametersInfo(SPI_GETWHEELSCROLLCHARS, 0, &scrollChars, 0))
56 scrollChars = 1;
57 return scrollChars;
58 }
59
verticalScrollLines()60 static int verticalScrollLines()
61 {
62 static ULONG scrollLines;
63 if (!scrollLines && !SystemParametersInfo(SPI_GETWHEELSCROLLLINES, 0, &scrollLines, 0))
64 scrollLines = 3;
65 return scrollLines;
66 }
67
PlatformWheelEvent(HWND hWnd,const FloatSize & delta,const FloatPoint & location)68 PlatformWheelEvent::PlatformWheelEvent(HWND hWnd, const FloatSize& delta, const FloatPoint& location)
69 : m_isAccepted(false)
70 , m_shiftKey(false)
71 , m_ctrlKey(false)
72 , m_altKey(false)
73 , m_metaKey(false)
74 {
75 m_deltaX = delta.width();
76 m_deltaY = delta.height();
77
78 m_wheelTicksX = m_deltaX;
79 m_wheelTicksY = m_deltaY;
80
81 // Global Position is just x, y location of event
82 POINT point = {location.x(), location.y()};
83 m_globalPosition = point;
84
85 // Position needs to be translated to our client
86 ScreenToClient(hWnd, &point);
87 m_position = point;
88 }
89
PlatformWheelEvent(HWND hWnd,WPARAM wParam,LPARAM lParam,bool isMouseHWheel)90 PlatformWheelEvent::PlatformWheelEvent(HWND hWnd, WPARAM wParam, LPARAM lParam, bool isMouseHWheel)
91 : m_position(positionForEvent(hWnd, lParam))
92 , m_globalPosition(globalPositionForEvent(hWnd, lParam))
93 , m_isAccepted(false)
94 , m_shiftKey(wParam & MK_SHIFT)
95 , m_ctrlKey(wParam & MK_CONTROL)
96 , m_altKey(GetKeyState(VK_MENU) & HIGH_BIT_MASK_SHORT)
97 , m_metaKey(m_altKey) // FIXME: We'll have to test other browsers
98 {
99 // How many pixels should we scroll per line? Gecko uses the height of the
100 // current line, which means scroll distance changes as you go through the
101 // page or go to different pages. IE 7 is ~50 px/line, although the value
102 // seems to vary slightly by page and zoom level. Since IE 7 has a
103 // smoothing algorithm on scrolling, it can get away with slightly larger
104 // scroll values without feeling jerky. Here we use 100 px per three lines
105 // (the default scroll amount on Windows is three lines per wheel tick).
106 static const float cScrollbarPixelsPerLine = 100.0f / 3.0f;
107 float delta = GET_WHEEL_DELTA_WPARAM(wParam) / static_cast<float>(WHEEL_DELTA);
108 if (isMouseHWheel) {
109 // Windows is <-- -/+ -->, WebKit wants <-- +/- -->, so we negate
110 // |delta| after saving the original value on the wheel tick member.
111 m_wheelTicksX = delta;
112 m_wheelTicksY = 0;
113 delta = -delta;
114 } else {
115 // Even though we use shift + vertical wheel to scroll horizontally in
116 // WebKit, we still note it as a vertical scroll on the wheel tick
117 // member, so that the DOM event we later construct will match the real
118 // hardware event better.
119 m_wheelTicksX = 0;
120 m_wheelTicksY = delta;
121 }
122 if (isMouseHWheel || m_shiftKey) {
123 m_deltaX = delta * static_cast<float>(horizontalScrollChars()) * cScrollbarPixelsPerLine;
124 m_deltaY = 0;
125 m_granularity = ScrollByPixelWheelEvent;
126 } else {
127 m_deltaX = 0;
128 m_deltaY = delta;
129 int verticalMultiplier = verticalScrollLines();
130 m_granularity = (verticalMultiplier == WHEEL_PAGESCROLL) ? ScrollByPageWheelEvent : ScrollByPixelWheelEvent;
131 if (m_granularity == ScrollByPixelWheelEvent)
132 m_deltaY *= static_cast<float>(verticalMultiplier) * cScrollbarPixelsPerLine;
133 }
134 }
135
136 }
137