content/common/input/web_input_event_traits.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/common/input/web_input_event_traits.h"
   6
   7 #include <bitset>
   8 #include <limits>
   9
  10 #include "base/logging.h"
  11 #include "base/strings/stringprintf.h"
  12
  13 using base::StringAppendF;
  14 using base::SStringPrintf;
  15 using blink::WebGestureEvent;
  16 using blink::WebInputEvent;
  17 using blink::WebKeyboardEvent;
  18 using blink::WebMouseEvent;
  19 using blink::WebMouseWheelEvent;
  20 using blink::WebTouchEvent;
  21 using blink::WebTouchPoint;
  22 using std::numeric_limits;
  23
  24 namespace content {
  25 namespace {
  26
  27 const int kInvalidTouchIndex = -1;
  28
  29 void ApppendEventDetails(const WebKeyboardEvent& event, std::string* result) {
  30   StringAppendF(result,
  31                 "{\n WinCode: %d\n NativeCode: %d\n IsSystem: %d\n"
  32                 " Text: %s\n UnmodifiedText: %s\n KeyIdentifier: %s\n}",
  33                 event.windowsKeyCode,
  34                 event.nativeKeyCode,
  35                 event.isSystemKey,
  36                 reinterpret_cast<const char*>(event.text),
  37                 reinterpret_cast<const char*>(event.unmodifiedText),
  38                 reinterpret_cast<const char*>(event.keyIdentifier));
  39 }
  40
  41 void ApppendEventDetails(const WebMouseEvent& event, std::string* result) {
  42   StringAppendF(result,
  43                 "{\n Button: %d\n Pos: (%d, %d)\n WindowPos: (%d, %d)\n"
  44                 " GlobalPos: (%d, %d)\n Movement: (%d, %d)\n Clicks: %d\n}",
  45                 event.button,
  46                 event.x,
  47                 event.y,
  48                 event.windowX,
  49                 event.windowY,
  50                 event.globalX,
  51                 event.globalY,
  52                 event.movementX,
  53                 event.movementY,
  54                 event.clickCount);
  55 }
  56
  57 void ApppendEventDetails(const WebMouseWheelEvent& event, std::string* result) {
  58   StringAppendF(result,
  59                 "{\n Delta: (%f, %f)\n WheelTicks: (%f, %f)\n Accel: (%f, %f)\n"
  60                 " ScrollByPage: %d\n HasPreciseScrollingDeltas: %d\n"
  61                 " Phase: (%d, %d)\n CanRubberband: (%d, %d)\n CanScroll: %d\n}",
  62                 event.deltaX,
  63                 event.deltaY,
  64                 event.wheelTicksX,
  65                 event.wheelTicksY,
  66                 event.accelerationRatioX,
  67                 event.accelerationRatioY,
  68                 event.scrollByPage,
  69                 event.hasPreciseScrollingDeltas,
  70                 event.phase,
  71                 event.momentumPhase,
  72                 event.canRubberbandLeft,
  73                 event.canRubberbandRight,
  74                 event.canScroll);
  75 }
  76
  77 void ApppendEventDetails(const WebGestureEvent& event, std::string* result) {
  78   StringAppendF(result,
  79                 "{\n Pos: (%d, %d)\n GlobalPos: (%d, %d)\n SourceDevice: %d\n"
  80                 " RawData: (%f, %f, %f, %f, %d)\n}",
  81                 event.x,
  82                 event.y,
  83                 event.globalX,
  84                 event.globalY,
  85                 event.sourceDevice,
  86                 event.data.scrollUpdate.deltaX,
  87                 event.data.scrollUpdate.deltaY,
  88                 event.data.scrollUpdate.velocityX,
  89                 event.data.scrollUpdate.velocityY,
  90                 event.data.scrollUpdate.previousUpdateInSequencePrevented);
  91 }
  92
  93 void ApppendTouchPointDetails(const WebTouchPoint& point, std::string* result) {
  94   StringAppendF(result,
  95                  "  (ID: %d, State: %d, ScreenPos: (%f, %f), Pos: (%f, %f),"
  96                      " Radius: (%f, %f), Rot: %f, Force: %f),\n",
  97   point.id,
  98   point.state,
  99   point.screenPosition.x,
 100   point.screenPosition.y,
 101   point.position.x,
 102   point.position.y,
 103   point.radiusX,
 104   point.radiusY,
 105   point.rotationAngle,
 106   point.force);
 107 }
 108
 109 void ApppendEventDetails(const WebTouchEvent& event, std::string* result) {
 110   StringAppendF(result,
 111                 "{\n Touches: %u, Cancelable: %d, CausesScrolling: %d,"
 112                 " uniqueTouchEventId: %u\n[\n",
 113                 event.touchesLength, event.cancelable,
 114                 event.causesScrollingIfUncanceled, event.uniqueTouchEventId);
 115   for (unsigned i = 0; i < event.touchesLength; ++i)
 116     ApppendTouchPointDetails(event.touches[i], result);
 117   result->append(" ]\n}");
 118 }
 119
 120 bool CanCoalesce(const WebKeyboardEvent& event_to_coalesce,
 121                  const WebKeyboardEvent& event) {
 122   return false;
 123 }
 124
 125 void Coalesce(const WebKeyboardEvent& event_to_coalesce,
 126               WebKeyboardEvent* event) {
 127   DCHECK(CanCoalesce(event_to_coalesce, *event));
 128 }
 129
 130 bool CanCoalesce(const WebMouseEvent& event_to_coalesce,
 131                  const WebMouseEvent& event) {
 132   return event.type == event_to_coalesce.type &&
 133          event.type == WebInputEvent::MouseMove;
 134 }
 135
 136 void Coalesce(const WebMouseEvent& event_to_coalesce, WebMouseEvent* event) {
 137   DCHECK(CanCoalesce(event_to_coalesce, *event));
 138   // Accumulate movement deltas.
 139   int x = event->movementX;
 140   int y = event->movementY;
 141   *event = event_to_coalesce;
 142   event->movementX += x;
 143   event->movementY += y;
 144 }
 145
 146 bool CanCoalesce(const WebMouseWheelEvent& event_to_coalesce,
 147                  const WebMouseWheelEvent& event) {
 148   return event.modifiers == event_to_coalesce.modifiers &&
 149          event.scrollByPage == event_to_coalesce.scrollByPage &&
 150          event.phase == event_to_coalesce.phase &&
 151          event.momentumPhase == event_to_coalesce.momentumPhase &&
 152          event.hasPreciseScrollingDeltas ==
 153              event_to_coalesce.hasPreciseScrollingDeltas &&
 154          event.canScroll == event_to_coalesce.canScroll;
 155 }
 156
 157 float GetUnacceleratedDelta(float accelerated_delta, float acceleration_ratio) {
 158   return accelerated_delta * acceleration_ratio;
 159 }
 160
 161 float GetAccelerationRatio(float accelerated_delta, float unaccelerated_delta) {
 162   if (unaccelerated_delta == 0.f || accelerated_delta == 0.f)
 163     return 1.f;
 164   return unaccelerated_delta / accelerated_delta;
 165 }
 166
 167 void Coalesce(const WebMouseWheelEvent& event_to_coalesce,
 168               WebMouseWheelEvent* event) {
 169   DCHECK(CanCoalesce(event_to_coalesce, *event));
 170   float unaccelerated_x =
 171       GetUnacceleratedDelta(event->deltaX,
 172                             event->accelerationRatioX) +
 173       GetUnacceleratedDelta(event_to_coalesce.deltaX,
 174                             event_to_coalesce.accelerationRatioX);
 175   float unaccelerated_y =
 176       GetUnacceleratedDelta(event->deltaY,
 177                             event->accelerationRatioY) +
 178       GetUnacceleratedDelta(event_to_coalesce.deltaY,
 179                             event_to_coalesce.accelerationRatioY);
 180   event->deltaX += event_to_coalesce.deltaX;
 181   event->deltaY += event_to_coalesce.deltaY;
 182   event->wheelTicksX += event_to_coalesce.wheelTicksX;
 183   event->wheelTicksY += event_to_coalesce.wheelTicksY;
 184   event->accelerationRatioX =
 185       GetAccelerationRatio(event->deltaX, unaccelerated_x);
 186   event->accelerationRatioY =
 187       GetAccelerationRatio(event->deltaY, unaccelerated_y);
 188   DCHECK_GE(event_to_coalesce.timeStampSeconds, event->timeStampSeconds);
 189   event->timeStampSeconds = event_to_coalesce.timeStampSeconds;
 190 }
 191
 192 // Returns |kInvalidTouchIndex| iff |event| lacks a touch with an ID of |id|.
 193 int GetIndexOfTouchID(const WebTouchEvent& event, int id) {
 194   for (unsigned i = 0; i < event.touchesLength; ++i) {
 195     if (event.touches[i].id == id)
 196       return i;
 197   }
 198   return kInvalidTouchIndex;
 199 }
 200
 201 bool CanCoalesce(const WebTouchEvent& event_to_coalesce,
 202                  const WebTouchEvent& event) {
 203   if (event.type != event_to_coalesce.type ||
 204       event.type != WebInputEvent::TouchMove ||
 205       event.modifiers != event_to_coalesce.modifiers ||
 206       event.touchesLength != event_to_coalesce.touchesLength ||
 207       event.touchesLength > WebTouchEvent::touchesLengthCap)
 208     return false;
 209
 210   static_assert(WebTouchEvent::touchesLengthCap <= sizeof(int32_t) * 8U,
 211                 "suboptimal touchesLengthCap size");
 212   // Ensure that we have a 1-to-1 mapping of pointer ids between touches.
 213   std::bitset<WebTouchEvent::touchesLengthCap> unmatched_event_touches(
 214       (1 << event.touchesLength) - 1);
 215   for (unsigned i = 0; i < event_to_coalesce.touchesLength; ++i) {
 216     int event_touch_index =
 217         GetIndexOfTouchID(event, event_to_coalesce.touches[i].id);
 218     if (event_touch_index == kInvalidTouchIndex)
 219       return false;
 220     if (!unmatched_event_touches[event_touch_index])
 221       return false;
 222     unmatched_event_touches[event_touch_index] = false;
 223   }
 224   return unmatched_event_touches.none();
 225 }
 226
 227 void Coalesce(const WebTouchEvent& event_to_coalesce, WebTouchEvent* event) {
 228   DCHECK(CanCoalesce(event_to_coalesce, *event));
 229   // The WebTouchPoints include absolute position information. So it is
 230   // sufficient to simply replace the previous event with the new event->
 231   // However, it is necessary to make sure that all the points have the
 232   // correct state, i.e. the touch-points that moved in the last event, but
 233   // didn't change in the current event, will have Stationary state. It is
 234   // necessary to change them back to Moved state.
 235   WebTouchEvent old_event = *event;
 236   *event = event_to_coalesce;
 237   for (unsigned i = 0; i < event->touchesLength; ++i) {
 238     int i_old = GetIndexOfTouchID(old_event, event->touches[i].id);
 239     if (old_event.touches[i_old].state == blink::WebTouchPoint::StateMoved)
 240       event->touches[i].state = blink::WebTouchPoint::StateMoved;
 241   }
 242   event->causesScrollingIfUncanceled |= old_event.causesScrollingIfUncanceled;
 243 }
 244
 245 bool CanCoalesce(const WebGestureEvent& event_to_coalesce,
 246                  const WebGestureEvent& event) {
 247   if (event.type != event_to_coalesce.type ||
 248       event.sourceDevice != event_to_coalesce.sourceDevice ||
 249       event.modifiers != event_to_coalesce.modifiers)
 250     return false;
 251
 252   if (event.type == WebInputEvent::GestureScrollUpdate)
 253     return true;
 254
 255   // GesturePinchUpdate scales can be combined only if they share a focal point,
 256   // e.g., with double-tap drag zoom.
 257   if (event.type == WebInputEvent::GesturePinchUpdate &&
 258       event.x == event_to_coalesce.x &&
 259       event.y == event_to_coalesce.y)
 260     return true;
 261
 262   return false;
 263 }
 264
 265 void Coalesce(const WebGestureEvent& event_to_coalesce,
 266               WebGestureEvent* event) {
 267   DCHECK(CanCoalesce(event_to_coalesce, *event));
 268   if (event->type == WebInputEvent::GestureScrollUpdate) {
 269     event->data.scrollUpdate.deltaX +=
 270         event_to_coalesce.data.scrollUpdate.deltaX;
 271     event->data.scrollUpdate.deltaY +=
 272         event_to_coalesce.data.scrollUpdate.deltaY;
 273     DCHECK_EQ(
 274         event->data.scrollUpdate.previousUpdateInSequencePrevented,
 275         event_to_coalesce.data.scrollUpdate.previousUpdateInSequencePrevented);
 276   } else if (event->type == WebInputEvent::GesturePinchUpdate) {
 277     event->data.pinchUpdate.scale *= event_to_coalesce.data.pinchUpdate.scale;
 278     // Ensure the scale remains bounded above 0 and below Infinity so that
 279     // we can reliably perform operations like log on the values.
 280     if (event->data.pinchUpdate.scale < numeric_limits<float>::min())
 281       event->data.pinchUpdate.scale = numeric_limits<float>::min();
 282     else if (event->data.pinchUpdate.scale > numeric_limits<float>::max())
 283       event->data.pinchUpdate.scale = numeric_limits<float>::max();
 284   }
 285 }
 286
 287 struct WebInputEventToString {
 288   template <class EventType>
 289   bool Execute(const WebInputEvent& event, std::string* result) const {
 290     SStringPrintf(result, "%s (Time: %lf, Modifiers: %d)\n",
 291                   WebInputEventTraits::GetName(event.type),
 292                   event.timeStampSeconds,
 293                   event.modifiers);
 294     const EventType& typed_event = static_cast<const EventType&>(event);
 295     ApppendEventDetails(typed_event, result);
 296     return true;
 297   }
 298 };
 299
 300 struct WebInputEventSize {
 301   template <class EventType>
 302   bool Execute(WebInputEvent::Type /* type */, size_t* type_size) const {
 303     *type_size = sizeof(EventType);
 304     return true;
 305   }
 306 };
 307
 308 struct WebInputEventClone {
 309   template <class EventType>
 310   bool Execute(const WebInputEvent& event,
 311                ScopedWebInputEvent* scoped_event) const {
 312     DCHECK_EQ(sizeof(EventType), event.size);
 313     *scoped_event = ScopedWebInputEvent(
 314         new EventType(static_cast<const EventType&>(event)));
 315     return true;
 316   }
 317 };
 318
 319 struct WebInputEventDelete {
 320   template <class EventType>
 321   bool Execute(WebInputEvent* event, bool* /* dummy_var */) const {
 322     if (!event)
 323       return false;
 324     DCHECK_EQ(sizeof(EventType), event->size);
 325     delete static_cast<EventType*>(event);
 326     return true;
 327   }
 328 };
 329
 330 struct WebInputEventCanCoalesce {
 331   template <class EventType>
 332   bool Execute(const WebInputEvent& event_to_coalesce,
 333                const WebInputEvent* event) const {
 334     if (event_to_coalesce.type != event->type)
 335       return false;
 336     DCHECK_EQ(sizeof(EventType), event->size);
 337     DCHECK_EQ(sizeof(EventType), event_to_coalesce.size);
 338     return CanCoalesce(static_cast<const EventType&>(event_to_coalesce),
 339                        *static_cast<const EventType*>(event));
 340   }
 341 };
 342
 343 struct WebInputEventCoalesce {
 344   template <class EventType>
 345   bool Execute(const WebInputEvent& event_to_coalesce,
 346                WebInputEvent* event) const {
 347     Coalesce(static_cast<const EventType&>(event_to_coalesce),
 348              static_cast<EventType*>(event));
 349     return true;
 350   }
 351 };
 352
 353 template <typename Operator, typename ArgIn, typename ArgOut>
 354 bool Apply(Operator op,
 355            WebInputEvent::Type type,
 356            const ArgIn& arg_in,
 357            ArgOut* arg_out) {
 358   if (WebInputEvent::isMouseEventType(type))
 359     return op.template Execute<WebMouseEvent>(arg_in, arg_out);
 360   else if (type == WebInputEvent::MouseWheel)
 361     return op.template Execute<WebMouseWheelEvent>(arg_in, arg_out);
 362   else if (WebInputEvent::isKeyboardEventType(type))
 363     return op.template Execute<WebKeyboardEvent>(arg_in, arg_out);
 364   else if (WebInputEvent::isTouchEventType(type))
 365     return op.template Execute<WebTouchEvent>(arg_in, arg_out);
 366   else if (WebInputEvent::isGestureEventType(type))
 367     return op.template Execute<WebGestureEvent>(arg_in, arg_out);
 368
 369   NOTREACHED() << "Unknown webkit event type " << type;
 370   return false;
 371 }
 372
 373 }  // namespace
 374
 375 const char* WebInputEventTraits::GetName(WebInputEvent::Type type) {
 376 #define CASE_TYPE(t) case WebInputEvent::t:  return #t
 377   switch(type) {
 378     CASE_TYPE(Undefined);
 379     CASE_TYPE(MouseDown);
 380     CASE_TYPE(MouseUp);
 381     CASE_TYPE(MouseMove);
 382     CASE_TYPE(MouseEnter);
 383     CASE_TYPE(MouseLeave);
 384     CASE_TYPE(ContextMenu);
 385     CASE_TYPE(MouseWheel);
 386     CASE_TYPE(RawKeyDown);
 387     CASE_TYPE(KeyDown);
 388     CASE_TYPE(KeyUp);
 389     CASE_TYPE(Char);
 390     CASE_TYPE(GestureScrollBegin);
 391     CASE_TYPE(GestureScrollEnd);
 392     CASE_TYPE(GestureScrollUpdate);
 393     CASE_TYPE(GestureFlingStart);
 394     CASE_TYPE(GestureFlingCancel);
 395     CASE_TYPE(GestureShowPress);
 396     CASE_TYPE(GestureTap);
 397     CASE_TYPE(GestureTapUnconfirmed);
 398     CASE_TYPE(GestureTapDown);
 399     CASE_TYPE(GestureTapCancel);
 400     CASE_TYPE(GestureDoubleTap);
 401     CASE_TYPE(GestureTwoFingerTap);
 402     CASE_TYPE(GestureLongPress);
 403     CASE_TYPE(GestureLongTap);
 404     CASE_TYPE(GesturePinchBegin);
 405     CASE_TYPE(GesturePinchEnd);
 406     CASE_TYPE(GesturePinchUpdate);
 407     CASE_TYPE(TouchStart);
 408     CASE_TYPE(TouchMove);
 409     CASE_TYPE(TouchEnd);
 410     CASE_TYPE(TouchCancel);
 411     default:
 412       // Must include default to let blink::WebInputEvent add new event types
 413       // before they're added here.
 414       DLOG(WARNING) <<
 415           "Unhandled WebInputEvent type in WebInputEventTraits::GetName.\n";
 416       break;
 417   }
 418 #undef CASE_TYPE
 419   return "";
 420 }
 421
 422 std::string WebInputEventTraits::ToString(const WebInputEvent& event) {
 423   std::string result;
 424   Apply(WebInputEventToString(), event.type, event, &result);
 425   return result;
 426 }
 427
 428 size_t WebInputEventTraits::GetSize(WebInputEvent::Type type) {
 429   size_t size = 0;
 430   Apply(WebInputEventSize(), type, type, &size);
 431   return size;
 432 }
 433
 434 ScopedWebInputEvent WebInputEventTraits::Clone(const WebInputEvent& event) {
 435   ScopedWebInputEvent scoped_event;
 436   Apply(WebInputEventClone(), event.type, event, &scoped_event);
 437   return scoped_event.Pass();
 438 }
 439
 440 void WebInputEventTraits::Delete(WebInputEvent* event) {
 441   if (!event)
 442     return;
 443   bool dummy_var = false;
 444   Apply(WebInputEventDelete(), event->type, event, &dummy_var);
 445 }
 446
 447 bool WebInputEventTraits::CanCoalesce(const WebInputEvent& event_to_coalesce,
 448                                       const WebInputEvent& event) {
 449   // Early out before casting.
 450   if (event_to_coalesce.type != event.type)
 451     return false;
 452   return Apply(WebInputEventCanCoalesce(),
 453                event.type,
 454                event_to_coalesce,
 455                &event);
 456 }
 457
 458 void WebInputEventTraits::Coalesce(const WebInputEvent& event_to_coalesce,
 459                                    WebInputEvent* event) {
 460   DCHECK(event);
 461   Apply(WebInputEventCoalesce(), event->type, event_to_coalesce, event);
 462 }
 463
 464 bool WebInputEventTraits::WillReceiveAckFromRenderer(
 465     const WebInputEvent& event) {
 466   switch (event.type) {
 467     case WebInputEvent::MouseDown:
 468     case WebInputEvent::MouseUp:
 469     case WebInputEvent::MouseEnter:
 470     case WebInputEvent::MouseLeave:
 471     case WebInputEvent::ContextMenu:
 472     case WebInputEvent::GestureScrollBegin:
 473     case WebInputEvent::GestureScrollEnd:
 474     case WebInputEvent::GestureShowPress:
 475     case WebInputEvent::GestureTapUnconfirmed:
 476     case WebInputEvent::GestureTapDown:
 477     case WebInputEvent::GestureTapCancel:
 478     case WebInputEvent::GesturePinchBegin:
 479     case WebInputEvent::GesturePinchEnd:
 480     case WebInputEvent::TouchCancel:
 481       return false;
 482     case WebInputEvent::TouchStart:
 483     case WebInputEvent::TouchEnd:
 484       return static_cast<const WebTouchEvent&>(event).cancelable;
 485     default:
 486       return true;
 487   }
 488 }
 489
 490 uint32 WebInputEventTraits::GetUniqueTouchEventId(const WebInputEvent& event) {
 491   if (WebInputEvent::isTouchEventType(event.type)) {
 492     return static_cast<const WebTouchEvent&>(event).uniqueTouchEventId;
 493   }
 494   return 0U;
 495 }
 496
 497 }  // namespace content