Bug 1648104 - Consume WM_POINTER with PT_TOUCH r=win-reviewers,rkraesig

Using WM_POINTER prevents touch and mouse pointer interfering each other, which is good for users who use both touchscreen and touchpad e.g. on Surface Pro.

Differential Revision: https://phabricator.services.mozilla.com/D236227

modules/libpref/init/StaticPrefList.yaml

@@ -5043,6 +5043,13 @@
     value: true
     mirror: always
 
+  # Control consuming WM_POINTER for touch pointers instead of WM_TOUCH
+-   name: dom.w3c_pointer_events.dispatch_by_pointer_messages.touch
+    type: bool
+    value: @IS_NIGHTLY_BUILD@
+    mirror: always
+
+  # Control whether to fire WidgetTouchEvent from pen pointers for APZ to handle scrolling.
 -   name: dom.w3c_pointer_events.scroll_by_pen.enabled
     type: bool
     value: true

widget/windows/WinPointerEvents.cpp

@@ -105,6 +105,21 @@ bool WinPointerEvents::GetPointerPenInfo(uint32_t aPointerId,
   return getPointerPenInfo(aPointerId, aPenInfo);
 }
 
+void WinPointerEvents::GetPointerFrameTouchInfo(
+    uint32_t pointerId, nsTArray<POINTER_TOUCH_INFO>& aTouchInfoArray) {
+  uint32_t pointerCount = 0;
+  if (!::GetPointerFrameTouchInfo(pointerId, &pointerCount, nullptr)) {
+    return;
+  }
+  if (!pointerCount) {
+    return;
+  }
+
+  aTouchInfoArray.SetLength(pointerCount);
+  ::GetPointerFrameTouchInfo(pointerId, &pointerCount,
+                             aTouchInfoArray.Elements());
+}
+
 bool WinPointerEvents::ShouldRollupOnPointerEvent(UINT aMsg, WPARAM aWParam) {
   MOZ_ASSERT(aMsg == WM_POINTERDOWN);
   // Only roll up popups when we handling WM_POINTER* to fire Gecko

widget/windows/WinPointerEvents.h

@@ -44,6 +44,8 @@ class WinPointerEvents final {
   POINTER_INPUT_TYPE GetPointerType(uint32_t aPointerId);
   bool GetPointerInfo(uint32_t aPointerId, POINTER_INFO* aPointerInfo);
   bool GetPointerPenInfo(uint32_t aPointerId, POINTER_PEN_INFO* aPenInfo);
+  void GetPointerFrameTouchInfo(uint32_t pointerId,
+                                nsTArray<POINTER_TOUCH_INFO>& aTouchInfoArray);
   bool ShouldRollupOnPointerEvent(UINT aMsg, WPARAM aWParam);
   bool ShouldFirePointerEventByWinPointerMessages();
   WinPointerInfo* GetCachedPointerInfo(UINT aMsg, WPARAM aWParam);

widget/windows/nsWindow.cpp

@@ -8035,22 +8035,43 @@ bool nsWindow::OnPointerEvents(UINT msg, WPARAM aWParam, LPARAM aLParam) {
     // which fallbacks to WM_LBUTTON* and WM_GESTURE, to keep consistency.
     return false;
   }
-  if (!mPointerEvents.ShouldHandleWinPointerMessages(msg, aWParam)) {
+
+  uint32_t pointerId = mPointerEvents.GetPointerId(aWParam);
+  POINTER_INPUT_TYPE pointerType = PT_POINTER;
+  if (!GetPointerType(pointerId, &pointerType)) {
+    MOZ_ASSERT(false, "cannot find PointerType");
     return false;
   }
+
+  if (pointerType == PT_TOUCH) {
+    if (!StaticPrefs::
+            dom_w3c_pointer_events_dispatch_by_pointer_messages_touch()) {
+      return false;
+    }
+    return OnTouchPointerEvents(pointerId, msg, aWParam, aLParam);
+  }
+
+  if (pointerType == PT_PEN) {
+    return OnPenPointerEvents(pointerId, msg, aWParam, aLParam);
+  }
+
+  return false;
+}
+
+bool nsWindow::OnPenPointerEvents(uint32_t aPointerId, UINT aMsg,
+                                  WPARAM aWParam, LPARAM aLParam) {
   if (!mPointerEvents.ShouldFirePointerEventByWinPointerMessages()) {
     // We have to handle WM_POINTER* to fetch and cache pen related information
     // and fire WidgetMouseEvent with the cached information the WM_*BUTTONDOWN
     // handler. This is because Windows doesn't support ::DoDragDrop in the
     // touch or pen message handlers.
-    mPointerEvents.ConvertAndCachePointerInfo(msg, aWParam);
+    mPointerEvents.ConvertAndCachePointerInfo(aMsg, aWParam);
     // Don't consume the Windows WM_POINTER* messages
     return false;
   }
 
-  uint32_t pointerId = mPointerEvents.GetPointerId(aWParam);
   POINTER_PEN_INFO penInfo{};
-  if (!mPointerEvents.GetPointerPenInfo(pointerId, &penInfo)) {
+  if (!mPointerEvents.GetPointerPenInfo(aPointerId, &penInfo)) {
     return false;
   }
 
@@ -8070,7 +8091,7 @@ bool nsWindow::OnPointerEvents(UINT msg, WPARAM aWParam, LPARAM aLParam) {
 
   EventMessage message;
   mozilla::MouseButton button = MouseButton::ePrimary;
-  switch (msg) {
+  switch (aMsg) {
     case WM_POINTERDOWN: {
       LayoutDeviceIntPoint eventPoint(GET_X_LPARAM(aLParam),
                                       GET_Y_LPARAM(aLParam));
@@ -8122,8 +8143,8 @@ bool nsWindow::OnPointerEvents(UINT msg, WPARAM aWParam, LPARAM aLParam) {
   float pressure = penInfo.pressure ? (float)penInfo.pressure / 1024 : 0;
   int16_t buttons = sPointerDown
                         ? nsContentUtils::GetButtonsFlagForButton(button)
-                        : MouseButtonsFlag::eNoButtons;
+                        : static_cast<int16_t>(MouseButtonsFlag::eNoButtons);
-  WinPointerInfo pointerInfo(pointerId, penInfo.tiltX, penInfo.tiltY, pressure,
+  WinPointerInfo pointerInfo(aPointerId, penInfo.tiltX, penInfo.tiltY, pressure,
                              buttons);
   // Per
   // https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-pointer_pen_info,
@@ -8134,7 +8155,7 @@ bool nsWindow::OnPointerEvents(UINT msg, WPARAM aWParam, LPARAM aLParam) {
   // Fire touch events but not when the barrel button is pressed.
   if (button != MouseButton::eSecondary &&
       StaticPrefs::dom_w3c_pointer_events_scroll_by_pen_enabled() &&
-      DispatchTouchEventFromWMPointer(msg, aLParam, pointerInfo, button)) {
+      DispatchTouchEventFromWMPointer(aMsg, aLParam, pointerInfo, button)) {
     return true;
   }
 
@@ -8155,6 +8176,71 @@ bool nsWindow::OnPointerEvents(UINT msg, WPARAM aWParam, LPARAM aLParam) {
   return true;
 }
 
+bool nsWindow::OnTouchPointerEvents(uint32_t aPointerId, UINT aMsg,
+                                    WPARAM aWParam, LPARAM aLParam) {
+  MultiTouchInput::MultiTouchType touchType;
+  switch (aMsg) {
+    case WM_POINTERDOWN:
+      touchType = MultiTouchInput::MULTITOUCH_START;
+      break;
+    case WM_POINTERUPDATE:
+      touchType = MultiTouchInput::MULTITOUCH_MOVE;
+      break;
+    case WM_POINTERUP:
+      touchType = MultiTouchInput::MULTITOUCH_END;
+      break;
+    default:
+      return false;
+  }
+
+  nsTArray<POINTER_TOUCH_INFO> touchInfoArray{};
+  mPointerEvents.GetPointerFrameTouchInfo(aPointerId, touchInfoArray);
+  if (touchInfoArray.IsEmpty()) {
+    return false;
+  }
+
+  MultiTouchInput inputToDispatch;
+  inputToDispatch.mInputType = MULTITOUCH_INPUT;
+  inputToDispatch.mType = touchType;
+  inputToDispatch.mTimeStamp = GetMessageTimeStamp(::GetMessageTime());
+
+  for (const POINTER_TOUCH_INFO& touchInfo : touchInfoArray) {
+    ScreenSize size(static_cast<float>(touchInfo.rcContact.right -
+                                       touchInfo.rcContact.left),
+                    static_cast<float>(touchInfo.rcContact.bottom -
+                                       touchInfo.rcContact.top));
+
+    nsPointWin touchPoint;
+    touchPoint.x = touchInfo.pointerInfo.ptPixelLocation.x;
+    touchPoint.y = touchInfo.pointerInfo.ptPixelLocation.y;
+    touchPoint.ScreenToClient(mWnd);
+
+    // Windows provides orientation info, but the behavior differs from
+    // TouchEvent because TouchEvent's angle rotates the elliptic contact region
+    // while the Windows provided orientation is independent from touch point
+    // rect.
+    //
+    // e.g. For a vertically long touch pointer, Windows would give vertically
+    // long rect and also give a 90 degree orientation, and passing both would
+    // incorrectly represent a horizontal ellipse.
+    //
+    // See also: https://w3c.github.io/touch-events/#dom-touch-rotationangle
+    // "The angle (in degrees) that the ellipse described by radiusX and radiusY
+    // is rotated clockwise about its center; 0 if no value is known."
+    float angle = 0.0f;
+
+    bool hasPressure = !!(touchInfo.touchMask & TOUCH_MASK_PRESSURE);
+    float pressure = hasPressure ? (float)touchInfo.pressure / 1024 : 0;
+    inputToDispatch.mTouches.AppendElement(
+        SingleTouchData(static_cast<int32_t>(touchInfo.pointerInfo.pointerId),
+                        ScreenIntPoint::FromUnknownPoint(touchPoint), size / 2,
+                        angle, pressure));
+  }
+
+  DispatchTouchInput(inputToDispatch);
+  return true;
+}
+
 void nsWindow::GetCompositorWidgetInitData(
     mozilla::widget::CompositorWidgetInitData* aInitData) {
   *aInitData = WinCompositorWidgetInitData(

widget/windows/nsWindow.h

@@ -609,6 +609,10 @@ class nsWindow final : public nsBaseWidget {
   void OnSysColorChanged();
   void OnDPIChanged(int32_t x, int32_t y, int32_t width, int32_t height);
   bool OnPointerEvents(UINT msg, WPARAM wParam, LPARAM lParam);
+  bool OnPenPointerEvents(uint32_t aPointerId, UINT aMsg, WPARAM aWParam,
+                          LPARAM aLParam);
+  bool OnTouchPointerEvents(uint32_t aPointerId, UINT aMsg, WPARAM aWParam,
+                            LPARAM aLParam);
 
   /**
    * Function that registers when the user has been active (used for detecting