Torne (Richard Coles) | 5c87bf8 | 2012-11-14 11:46:17 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006-2009 Google 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 are |
| 6 | * met: |
| 7 | * |
| 8 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above |
| 11 | * copyright notice, this list of conditions and the following disclaimer |
| 12 | * in the documentation and/or other materials provided with the |
| 13 | * distribution. |
| 14 | * * Neither the name of Google Inc. nor the names of its |
| 15 | * contributors may be used to endorse or promote products derived from |
| 16 | * this software without specific prior written permission. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 19 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 20 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 21 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 22 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 23 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 24 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 25 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 26 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 27 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 28 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | */ |
| 30 | |
| 31 | #include "config.h" |
| 32 | #include "WebInputEventFactory.h" |
| 33 | |
| 34 | #include "WebInputEvent.h" |
| 35 | |
Ben Murdoch | 591b958 | 2013-07-10 11:41:44 +0100 | [diff] [blame] | 36 | #include "wtf/Assertions.h" |
Torne (Richard Coles) | 5c87bf8 | 2012-11-14 11:46:17 +0000 | [diff] [blame] | 37 | |
Torne (Richard Coles) | 51b2906 | 2013-11-28 11:56:03 +0000 | [diff] [blame] | 38 | namespace blink { |
Torne (Richard Coles) | 5c87bf8 | 2012-11-14 11:46:17 +0000 | [diff] [blame] | 39 | |
| 40 | static const unsigned long defaultScrollLinesPerWheelDelta = 3; |
| 41 | static const unsigned long defaultScrollCharsPerWheelDelta = 1; |
| 42 | |
| 43 | // WebKeyboardEvent ----------------------------------------------------------- |
| 44 | |
| 45 | static bool isKeyDown(WPARAM wparam) |
| 46 | { |
| 47 | return GetKeyState(wparam) & 0x8000; |
| 48 | } |
| 49 | |
| 50 | static int getLocationModifier(WPARAM wparam, LPARAM lparam) |
| 51 | { |
| 52 | int modifier = 0; |
| 53 | switch (wparam) { |
| 54 | case VK_RETURN: |
| 55 | if ((lparam >> 16) & KF_EXTENDED) |
| 56 | modifier = WebInputEvent::IsKeyPad; |
| 57 | break; |
| 58 | case VK_INSERT: |
| 59 | case VK_DELETE: |
| 60 | case VK_HOME: |
| 61 | case VK_END: |
| 62 | case VK_PRIOR: |
| 63 | case VK_NEXT: |
| 64 | case VK_UP: |
| 65 | case VK_DOWN: |
| 66 | case VK_LEFT: |
| 67 | case VK_RIGHT: |
| 68 | if (!((lparam >> 16) & KF_EXTENDED)) |
| 69 | modifier = WebInputEvent::IsKeyPad; |
| 70 | break; |
Torne (Richard Coles) | 5c87bf8 | 2012-11-14 11:46:17 +0000 | [diff] [blame] | 71 | case VK_NUMPAD0: |
| 72 | case VK_NUMPAD1: |
| 73 | case VK_NUMPAD2: |
| 74 | case VK_NUMPAD3: |
| 75 | case VK_NUMPAD4: |
| 76 | case VK_NUMPAD5: |
| 77 | case VK_NUMPAD6: |
| 78 | case VK_NUMPAD7: |
| 79 | case VK_NUMPAD8: |
| 80 | case VK_NUMPAD9: |
| 81 | case VK_DIVIDE: |
| 82 | case VK_MULTIPLY: |
| 83 | case VK_SUBTRACT: |
| 84 | case VK_ADD: |
| 85 | case VK_DECIMAL: |
| 86 | case VK_CLEAR: |
| 87 | modifier = WebInputEvent::IsKeyPad; |
| 88 | break; |
| 89 | case VK_SHIFT: |
| 90 | if (isKeyDown(VK_LSHIFT)) |
| 91 | modifier = WebInputEvent::IsLeft; |
| 92 | else if (isKeyDown(VK_RSHIFT)) |
| 93 | modifier = WebInputEvent::IsRight; |
| 94 | break; |
| 95 | case VK_CONTROL: |
| 96 | if (isKeyDown(VK_LCONTROL)) |
| 97 | modifier = WebInputEvent::IsLeft; |
| 98 | else if (isKeyDown(VK_RCONTROL)) |
| 99 | modifier = WebInputEvent::IsRight; |
| 100 | break; |
| 101 | case VK_MENU: |
| 102 | if (isKeyDown(VK_LMENU)) |
| 103 | modifier = WebInputEvent::IsLeft; |
| 104 | else if (isKeyDown(VK_RMENU)) |
| 105 | modifier = WebInputEvent::IsRight; |
| 106 | break; |
| 107 | case VK_LWIN: |
| 108 | modifier = WebInputEvent::IsLeft; |
| 109 | break; |
| 110 | case VK_RWIN: |
| 111 | modifier = WebInputEvent::IsRight; |
| 112 | break; |
| 113 | } |
| 114 | |
| 115 | ASSERT(!modifier |
| 116 | || modifier == WebInputEvent::IsKeyPad |
| 117 | || modifier == WebInputEvent::IsLeft |
| 118 | || modifier == WebInputEvent::IsRight); |
| 119 | return modifier; |
| 120 | } |
| 121 | |
| 122 | // Loads the state for toggle keys into the event. |
| 123 | static void SetToggleKeyState(WebInputEvent* event) |
| 124 | { |
| 125 | // Low bit set from GetKeyState indicates "toggled". |
| 126 | if (::GetKeyState(VK_NUMLOCK) & 1) |
| 127 | event->modifiers |= WebInputEvent::NumLockOn; |
| 128 | if (::GetKeyState(VK_CAPITAL) & 1) |
| 129 | event->modifiers |= WebInputEvent::CapsLockOn; |
| 130 | } |
| 131 | |
| 132 | WebKeyboardEvent WebInputEventFactory::keyboardEvent(HWND hwnd, UINT message, |
| 133 | WPARAM wparam, LPARAM lparam) |
| 134 | { |
| 135 | WebKeyboardEvent result; |
| 136 | |
| 137 | // TODO(pkasting): http://b/1117926 Are we guaranteed that the message that |
| 138 | // GetMessageTime() refers to is the same one that we're passed in? Perhaps |
| 139 | // one of the construction parameters should be the time passed by the |
| 140 | // caller, who would know for sure. |
| 141 | result.timeStampSeconds = GetMessageTime() / 1000.0; |
| 142 | |
| 143 | result.windowsKeyCode = static_cast<int>(wparam); |
| 144 | // Record the scan code (along with other context bits) for this key event. |
| 145 | result.nativeKeyCode = static_cast<int>(lparam); |
| 146 | |
| 147 | switch (message) { |
| 148 | case WM_SYSKEYDOWN: |
| 149 | result.isSystemKey = true; |
| 150 | case WM_KEYDOWN: |
| 151 | result.type = WebInputEvent::RawKeyDown; |
| 152 | break; |
| 153 | case WM_SYSKEYUP: |
| 154 | result.isSystemKey = true; |
| 155 | case WM_KEYUP: |
| 156 | result.type = WebInputEvent::KeyUp; |
| 157 | break; |
| 158 | case WM_IME_CHAR: |
| 159 | result.type = WebInputEvent::Char; |
| 160 | break; |
| 161 | case WM_SYSCHAR: |
| 162 | result.isSystemKey = true; |
| 163 | result.type = WebInputEvent::Char; |
| 164 | case WM_CHAR: |
| 165 | result.type = WebInputEvent::Char; |
| 166 | break; |
| 167 | default: |
| 168 | ASSERT_NOT_REACHED(); |
| 169 | } |
| 170 | |
| 171 | if (result.type == WebInputEvent::Char || result.type == WebInputEvent::RawKeyDown) { |
| 172 | result.text[0] = result.windowsKeyCode; |
| 173 | result.unmodifiedText[0] = result.windowsKeyCode; |
| 174 | } |
| 175 | if (result.type != WebInputEvent::Char) |
| 176 | result.setKeyIdentifierFromWindowsKeyCode(); |
| 177 | |
| 178 | if (GetKeyState(VK_SHIFT) & 0x8000) |
| 179 | result.modifiers |= WebInputEvent::ShiftKey; |
| 180 | if (GetKeyState(VK_CONTROL) & 0x8000) |
| 181 | result.modifiers |= WebInputEvent::ControlKey; |
| 182 | if (GetKeyState(VK_MENU) & 0x8000) |
| 183 | result.modifiers |= WebInputEvent::AltKey; |
| 184 | // NOTE: There doesn't seem to be a way to query the mouse button state in |
| 185 | // this case. |
| 186 | |
| 187 | if (LOWORD(lparam) > 1) |
| 188 | result.modifiers |= WebInputEvent::IsAutoRepeat; |
| 189 | |
| 190 | result.modifiers |= getLocationModifier(wparam, lparam); |
| 191 | |
| 192 | SetToggleKeyState(&result); |
| 193 | return result; |
| 194 | } |
| 195 | |
| 196 | // WebMouseEvent -------------------------------------------------------------- |
| 197 | |
| 198 | static int gLastClickCount; |
| 199 | static double gLastClickTime; |
| 200 | |
| 201 | static LPARAM GetRelativeCursorPos(HWND hwnd) |
| 202 | { |
| 203 | POINT pos = {-1, -1}; |
| 204 | GetCursorPos(&pos); |
| 205 | ScreenToClient(hwnd, &pos); |
| 206 | return MAKELPARAM(pos.x, pos.y); |
| 207 | } |
| 208 | |
| 209 | void WebInputEventFactory::resetLastClickState() |
| 210 | { |
| 211 | gLastClickTime = gLastClickCount = 0; |
| 212 | } |
| 213 | |
Torne (Richard Coles) | 51b2906 | 2013-11-28 11:56:03 +0000 | [diff] [blame] | 214 | bool WebInputEventFactory::isSystemKeyEvent(const WebKeyboardEvent& event) |
| 215 | { |
| 216 | // According to MSDN: |
| 217 | // http://msdn.microsoft.com/en-us/library/ms646286(VS.85).aspx |
| 218 | // Key events with Alt modifier and F10 are system key events. |
| 219 | // We just emulate this behavior. It's necessary to prevent webkit from |
| 220 | // processing keypress event generated by alt-d, etc. |
| 221 | return event.modifiers & WebInputEvent::AltKey || event.windowsKeyCode == VK_F10; |
| 222 | } |
| 223 | |
Torne (Richard Coles) | 5c87bf8 | 2012-11-14 11:46:17 +0000 | [diff] [blame] | 224 | WebMouseEvent WebInputEventFactory::mouseEvent(HWND hwnd, UINT message, |
| 225 | WPARAM wparam, LPARAM lparam) |
| 226 | { |
| 227 | WebMouseEvent result; //(WebInputEvent::Uninitialized()); |
| 228 | |
| 229 | switch (message) { |
| 230 | case WM_MOUSEMOVE: |
| 231 | result.type = WebInputEvent::MouseMove; |
| 232 | if (wparam & MK_LBUTTON) |
| 233 | result.button = WebMouseEvent::ButtonLeft; |
| 234 | else if (wparam & MK_MBUTTON) |
| 235 | result.button = WebMouseEvent::ButtonMiddle; |
| 236 | else if (wparam & MK_RBUTTON) |
| 237 | result.button = WebMouseEvent::ButtonRight; |
| 238 | else |
| 239 | result.button = WebMouseEvent::ButtonNone; |
| 240 | break; |
| 241 | case WM_MOUSELEAVE: |
| 242 | result.type = WebInputEvent::MouseLeave; |
| 243 | result.button = WebMouseEvent::ButtonNone; |
| 244 | // set the current mouse position (relative to the client area of the |
| 245 | // current window) since none is specified for this event |
| 246 | lparam = GetRelativeCursorPos(hwnd); |
| 247 | break; |
| 248 | case WM_LBUTTONDOWN: |
| 249 | case WM_LBUTTONDBLCLK: |
| 250 | result.type = WebInputEvent::MouseDown; |
| 251 | result.button = WebMouseEvent::ButtonLeft; |
| 252 | break; |
| 253 | case WM_MBUTTONDOWN: |
| 254 | case WM_MBUTTONDBLCLK: |
| 255 | result.type = WebInputEvent::MouseDown; |
| 256 | result.button = WebMouseEvent::ButtonMiddle; |
| 257 | break; |
| 258 | case WM_RBUTTONDOWN: |
| 259 | case WM_RBUTTONDBLCLK: |
| 260 | result.type = WebInputEvent::MouseDown; |
| 261 | result.button = WebMouseEvent::ButtonRight; |
| 262 | break; |
| 263 | case WM_LBUTTONUP: |
| 264 | result.type = WebInputEvent::MouseUp; |
| 265 | result.button = WebMouseEvent::ButtonLeft; |
| 266 | break; |
| 267 | case WM_MBUTTONUP: |
| 268 | result.type = WebInputEvent::MouseUp; |
| 269 | result.button = WebMouseEvent::ButtonMiddle; |
| 270 | break; |
| 271 | case WM_RBUTTONUP: |
| 272 | result.type = WebInputEvent::MouseUp; |
| 273 | result.button = WebMouseEvent::ButtonRight; |
| 274 | break; |
| 275 | default: |
| 276 | ASSERT_NOT_REACHED(); |
| 277 | } |
| 278 | |
| 279 | // TODO(pkasting): http://b/1117926 Are we guaranteed that the message that |
| 280 | // GetMessageTime() refers to is the same one that we're passed in? Perhaps |
| 281 | // one of the construction parameters should be the time passed by the |
| 282 | // caller, who would know for sure. |
| 283 | result.timeStampSeconds = GetMessageTime() / 1000.0; |
| 284 | |
| 285 | // set position fields: |
| 286 | |
| 287 | result.x = static_cast<short>(LOWORD(lparam)); |
| 288 | result.y = static_cast<short>(HIWORD(lparam)); |
| 289 | result.windowX = result.x; |
| 290 | result.windowY = result.y; |
| 291 | |
| 292 | POINT globalPoint = { result.x, result.y }; |
| 293 | ClientToScreen(hwnd, &globalPoint); |
| 294 | |
| 295 | result.globalX = globalPoint.x; |
| 296 | result.globalY = globalPoint.y; |
| 297 | |
| 298 | // calculate number of clicks: |
| 299 | |
| 300 | // This differs slightly from the WebKit code in WebKit/win/WebView.cpp |
| 301 | // where their original code looks buggy. |
| 302 | static int lastClickPositionX; |
| 303 | static int lastClickPositionY; |
| 304 | static WebMouseEvent::Button lastClickButton = WebMouseEvent::ButtonLeft; |
| 305 | |
| 306 | double currentTime = result.timeStampSeconds; |
| 307 | bool cancelPreviousClick = |
| 308 | (abs(lastClickPositionX - result.x) > (GetSystemMetrics(SM_CXDOUBLECLK) / 2)) |
| 309 | || (abs(lastClickPositionY - result.y) > (GetSystemMetrics(SM_CYDOUBLECLK) / 2)) |
| 310 | || ((currentTime - gLastClickTime) * 1000.0 > GetDoubleClickTime()); |
| 311 | |
| 312 | if (result.type == WebInputEvent::MouseDown) { |
| 313 | if (!cancelPreviousClick && (result.button == lastClickButton)) |
| 314 | ++gLastClickCount; |
| 315 | else { |
| 316 | gLastClickCount = 1; |
| 317 | lastClickPositionX = result.x; |
| 318 | lastClickPositionY = result.y; |
| 319 | } |
| 320 | gLastClickTime = currentTime; |
| 321 | lastClickButton = result.button; |
| 322 | } else if (result.type == WebInputEvent::MouseMove |
| 323 | || result.type == WebInputEvent::MouseLeave) { |
| 324 | if (cancelPreviousClick) { |
| 325 | gLastClickCount = 0; |
| 326 | lastClickPositionX = 0; |
| 327 | lastClickPositionY = 0; |
| 328 | gLastClickTime = 0; |
| 329 | } |
| 330 | } |
| 331 | result.clickCount = gLastClickCount; |
| 332 | |
| 333 | // set modifiers: |
| 334 | |
| 335 | if (wparam & MK_CONTROL) |
| 336 | result.modifiers |= WebInputEvent::ControlKey; |
| 337 | if (wparam & MK_SHIFT) |
| 338 | result.modifiers |= WebInputEvent::ShiftKey; |
| 339 | if (GetKeyState(VK_MENU) & 0x8000) |
| 340 | result.modifiers |= WebInputEvent::AltKey; |
| 341 | if (wparam & MK_LBUTTON) |
| 342 | result.modifiers |= WebInputEvent::LeftButtonDown; |
| 343 | if (wparam & MK_MBUTTON) |
| 344 | result.modifiers |= WebInputEvent::MiddleButtonDown; |
| 345 | if (wparam & MK_RBUTTON) |
| 346 | result.modifiers |= WebInputEvent::RightButtonDown; |
| 347 | |
| 348 | SetToggleKeyState(&result); |
| 349 | return result; |
| 350 | } |
| 351 | |
| 352 | // WebMouseWheelEvent --------------------------------------------------------- |
| 353 | |
| 354 | WebMouseWheelEvent WebInputEventFactory::mouseWheelEvent(HWND hwnd, UINT message, |
| 355 | WPARAM wparam, LPARAM lparam) |
| 356 | { |
| 357 | WebMouseWheelEvent result; //(WebInputEvent::Uninitialized()); |
| 358 | |
| 359 | result.type = WebInputEvent::MouseWheel; |
| 360 | |
| 361 | // TODO(pkasting): http://b/1117926 Are we guaranteed that the message that |
| 362 | // GetMessageTime() refers to is the same one that we're passed in? Perhaps |
| 363 | // one of the construction parameters should be the time passed by the |
| 364 | // caller, who would know for sure. |
| 365 | result.timeStampSeconds = GetMessageTime() / 1000.0; |
| 366 | |
| 367 | result.button = WebMouseEvent::ButtonNone; |
| 368 | |
| 369 | // Get key state, coordinates, and wheel delta from event. |
| 370 | typedef SHORT (WINAPI *GetKeyStateFunction)(int key); |
| 371 | GetKeyStateFunction getKeyState; |
| 372 | UINT keyState; |
| 373 | float wheelDelta; |
| 374 | bool horizontalScroll = false; |
| 375 | if ((message == WM_VSCROLL) || (message == WM_HSCROLL)) { |
| 376 | // Synthesize mousewheel event from a scroll event. This is needed to |
| 377 | // simulate middle mouse scrolling in some laptops. Use GetAsyncKeyState |
| 378 | // for key state since we are synthesizing the input event. |
| 379 | getKeyState = GetAsyncKeyState; |
| 380 | keyState = 0; |
| 381 | if (getKeyState(VK_SHIFT)) |
| 382 | keyState |= MK_SHIFT; |
| 383 | if (getKeyState(VK_CONTROL)) |
| 384 | keyState |= MK_CONTROL; |
| 385 | // NOTE: There doesn't seem to be a way to query the mouse button state |
| 386 | // in this case. |
| 387 | |
| 388 | POINT cursorPosition = {0}; |
| 389 | GetCursorPos(&cursorPosition); |
| 390 | result.globalX = cursorPosition.x; |
| 391 | result.globalY = cursorPosition.y; |
| 392 | |
| 393 | switch (LOWORD(wparam)) { |
| 394 | case SB_LINEUP: // == SB_LINELEFT |
| 395 | wheelDelta = WHEEL_DELTA; |
| 396 | break; |
| 397 | case SB_LINEDOWN: // == SB_LINERIGHT |
| 398 | wheelDelta = -WHEEL_DELTA; |
| 399 | break; |
| 400 | case SB_PAGEUP: |
| 401 | wheelDelta = 1; |
| 402 | result.scrollByPage = true; |
| 403 | break; |
| 404 | case SB_PAGEDOWN: |
| 405 | wheelDelta = -1; |
| 406 | result.scrollByPage = true; |
| 407 | break; |
| 408 | default: // We don't supoprt SB_THUMBPOSITION or SB_THUMBTRACK here. |
| 409 | wheelDelta = 0; |
| 410 | break; |
| 411 | } |
| 412 | |
| 413 | if (message == WM_HSCROLL) |
| 414 | horizontalScroll = true; |
| 415 | } else { |
| 416 | // Non-synthesized event; we can just read data off the event. |
| 417 | getKeyState = GetKeyState; |
| 418 | keyState = GET_KEYSTATE_WPARAM(wparam); |
| 419 | |
| 420 | result.globalX = static_cast<short>(LOWORD(lparam)); |
| 421 | result.globalY = static_cast<short>(HIWORD(lparam)); |
| 422 | |
| 423 | wheelDelta = static_cast<float>(GET_WHEEL_DELTA_WPARAM(wparam)); |
| 424 | if (message == WM_MOUSEHWHEEL) { |
| 425 | horizontalScroll = true; |
| 426 | wheelDelta = -wheelDelta; // Windows is <- -/+ ->, WebKit <- +/- ->. |
| 427 | } |
| 428 | } |
| 429 | if (keyState & MK_SHIFT) |
| 430 | horizontalScroll = true; |
| 431 | |
| 432 | // Set modifiers based on key state. |
| 433 | if (keyState & MK_SHIFT) |
| 434 | result.modifiers |= WebInputEvent::ShiftKey; |
| 435 | if (keyState & MK_CONTROL) |
| 436 | result.modifiers |= WebInputEvent::ControlKey; |
| 437 | if (getKeyState(VK_MENU) & 0x8000) |
| 438 | result.modifiers |= WebInputEvent::AltKey; |
| 439 | if (keyState & MK_LBUTTON) |
| 440 | result.modifiers |= WebInputEvent::LeftButtonDown; |
| 441 | if (keyState & MK_MBUTTON) |
| 442 | result.modifiers |= WebInputEvent::MiddleButtonDown; |
| 443 | if (keyState & MK_RBUTTON) |
| 444 | result.modifiers |= WebInputEvent::RightButtonDown; |
| 445 | |
| 446 | SetToggleKeyState(&result); |
| 447 | |
| 448 | // Set coordinates by translating event coordinates from screen to client. |
| 449 | POINT clientPoint = { result.globalX, result.globalY }; |
| 450 | MapWindowPoints(0, hwnd, &clientPoint, 1); |
| 451 | result.x = clientPoint.x; |
| 452 | result.y = clientPoint.y; |
| 453 | result.windowX = result.x; |
| 454 | result.windowY = result.y; |
| 455 | |
| 456 | // Convert wheel delta amount to a number of pixels to scroll. |
| 457 | // |
| 458 | // How many pixels should we scroll per line? Gecko uses the height of the |
| 459 | // current line, which means scroll distance changes as you go through the |
| 460 | // page or go to different pages. IE 8 is ~60 px/line, although the value |
| 461 | // seems to vary slightly by page and zoom level. Also, IE defaults to |
| 462 | // smooth scrolling while Firefox doesn't, so it can get away with somewhat |
| 463 | // larger scroll values without feeling as jerky. Here we use 100 px per |
| 464 | // three lines (the default scroll amount is three lines per wheel tick). |
| 465 | // Even though we have smooth scrolling, we don't make this as large as IE |
| 466 | // because subjectively IE feels like it scrolls farther than you want while |
| 467 | // reading articles. |
| 468 | static const float scrollbarPixelsPerLine = 100.0f / 3.0f; |
| 469 | wheelDelta /= WHEEL_DELTA; |
| 470 | float scrollDelta = wheelDelta; |
| 471 | if (horizontalScroll) { |
| 472 | unsigned long scrollChars = defaultScrollCharsPerWheelDelta; |
| 473 | SystemParametersInfo(SPI_GETWHEELSCROLLCHARS, 0, &scrollChars, 0); |
| 474 | // TODO(pkasting): Should probably have a different multiplier |
| 475 | // scrollbarPixelsPerChar here. |
| 476 | scrollDelta *= static_cast<float>(scrollChars) * scrollbarPixelsPerLine; |
| 477 | } else { |
| 478 | unsigned long scrollLines = defaultScrollLinesPerWheelDelta; |
| 479 | SystemParametersInfo(SPI_GETWHEELSCROLLLINES, 0, &scrollLines, 0); |
| 480 | if (scrollLines == WHEEL_PAGESCROLL) |
| 481 | result.scrollByPage = true; |
| 482 | if (!result.scrollByPage) |
| 483 | scrollDelta *= static_cast<float>(scrollLines) * scrollbarPixelsPerLine; |
| 484 | } |
| 485 | |
| 486 | // Set scroll amount based on above calculations. WebKit expects positive |
| 487 | // deltaY to mean "scroll up" and positive deltaX to mean "scroll left". |
| 488 | if (horizontalScroll) { |
| 489 | result.deltaX = scrollDelta; |
| 490 | result.wheelTicksX = wheelDelta; |
| 491 | } else { |
| 492 | result.deltaY = scrollDelta; |
| 493 | result.wheelTicksY = wheelDelta; |
| 494 | } |
| 495 | |
| 496 | return result; |
| 497 | } |
| 498 | |
Torne (Richard Coles) | 51b2906 | 2013-11-28 11:56:03 +0000 | [diff] [blame] | 499 | } // namespace blink |