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 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 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 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 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 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 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