Windows Host Touch Injection

remoting/host/touch_injector_win.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "remoting/host/touch_injector_win.h"
+
+#include "base/files/file_path.h"
+#include "base/logging.h"
+#include "base/native_library.h"
+#include "base/stl_util.h"
+#include "remoting/proto/event.pb.h"
+
+namespace remoting {
+
+using protocol::TouchEvent;
+using protocol::TouchEventPoint;
+
+namespace {
+
+typedef BOOL(NTAPI* InitializeTouchInjectionFunction)(UINT32, DWORD);
+typedef BOOL(NTAPI* InjectTouchInputFunction)(UINT32,
+                                              const POINTER_TOUCH_INFO*);
+const uint32_t kMaxSimultaneousTouchCount = 10;
+
+// This is used to reinject all points that have not changed as "move"ed point,

[Wez, 2015/03/21 01:10:09]

typo: points

[Rintaro Kuroiwa, 2015/03/24 20:34:47]

Done.

+// even if it has not actually moved.

[Wez, 2015/03/21 01:10:09]

s/it has/they have

[Rintaro Kuroiwa, 2015/03/24 20:34:47]

Done.

+// This is required for multi-touch to work, e.g. pinching and zooming gestures
+// (handled by apps) won't work without reinjection the points even though the

[Wez, 2015/03/21 01:10:09]

s/reinjection/reinjecting

[Rintaro Kuroiwa, 2015/03/24 20:34:47]

Done.

+// user moved only one finger and held the other finger in place.
+void AppendMapValuesToVector(
+    std::map<uint32_t, POINTER_TOUCH_INFO>* touches_in_contact,
+    std::vector<POINTER_TOUCH_INFO>* output_vector) {
+  for (auto& id_and_pointer_touch_info : *touches_in_contact) {
+    POINTER_TOUCH_INFO& pointer_touch_info = id_and_pointer_touch_info.second;
+    output_vector->push_back(pointer_touch_info);
+  }
+}
+
+// The caller should set memset(0) the struct and set
+// pointer_touch_info->pointerInfo.pointerFlags.
+void ConvertToPointerTouchInfo(
+    const TouchEventPoint& touch_point,
+    POINTER_TOUCH_INFO* pointer_touch_info) {
+  pointer_touch_info->touchMask =
+      TOUCH_MASK_CONTACTAREA | TOUCH_MASK_ORIENTATION;
+  pointer_touch_info->touchFlags = TOUCH_FLAG_NONE;
+
+  // Although radius_{x,y} can be undefined (i.e. has_radius_{x,y} == false),
+  // the default value (0.0) will set the area correctly.
+  // MSDN mentions that if the digitizer does not detect the size of the touch
+  // point, rcContact should be set to 0 by 0 rectangle centered at the
+  // coordinate.
+  pointer_touch_info->rcContact.left =
+      touch_point.x() - touch_point.radius_x();
+  pointer_touch_info->rcContact.top = touch_point.y() - touch_point.radius_y();
+  pointer_touch_info->rcContact.right =
+      touch_point.x() + touch_point.radius_x();
+  pointer_touch_info->rcContact.bottom =
+      touch_point.y() + touch_point.radius_y();
+
+  pointer_touch_info->orientation = touch_point.angle();
+
+  if (touch_point.has_pressure()) {
+    pointer_touch_info->touchMask |= TOUCH_MASK_PRESSURE;
+    const float kMinimumPressure = 0.0;
+    const float kMaximumPressure = 1.0;
+    float clamped_touch_point_pressure = touch_point.pressure();

[Wez, 2015/03/21 01:10:08]

Use std::min and std::max here?

[Rintaro Kuroiwa, 2015/03/24 20:34:47]

Done.

+    if (clamped_touch_point_pressure < kMinimumPressure) {
+      clamped_touch_point_pressure = kMinimumPressure;
+    } else if (clamped_touch_point_pressure > kMaximumPressure) {
+      clamped_touch_point_pressure = kMaximumPressure;
+    }
+
+    const int kWindowsMaxTouchPressure = 1024;  // Defined in MSDN.
+    const int pressure =
+        clamped_touch_point_pressure * kWindowsMaxTouchPressure;
+    pointer_touch_info->pressure = pressure;
+  }
+
+  pointer_touch_info->pointerInfo.pointerType = PT_TOUCH;
+  pointer_touch_info->pointerInfo.pointerId = touch_point.id();
+  pointer_touch_info->pointerInfo.ptPixelLocation.x = touch_point.x();
+  pointer_touch_info->pointerInfo.ptPixelLocation.y = touch_point.y();
+}
+
+}  // namespace
+
+TouchInjectorWinDelegate::~TouchInjectorWinDelegate() {}
+
+// static.
+scoped_ptr<TouchInjectorWinDelegate> TouchInjectorWinDelegate::Create() {
+  base::ScopedNativeLibrary library(base::FilePath(L"User32.dll"));
+  if (!library.is_valid()) {
+    PLOG(INFO) << "Failed to get library module for touch injection functions.";
+    return scoped_ptr<TouchInjectorWinDelegate>();
+  }
+
+  InitializeTouchInjectionFunction init_func =
+      reinterpret_cast<InitializeTouchInjectionFunction>(
+          library.GetFunctionPointer("InitializeTouchInjection"));
+  if (!init_func) {
+    PLOG(INFO) << "Failed to get InitializeTouchInjection function handle.";
+    return scoped_ptr<TouchInjectorWinDelegate>();
+  }
+
+  InjectTouchInputFunction inject_touch_func =
+      reinterpret_cast<InjectTouchInputFunction>(
+          library.GetFunctionPointer("InjectTouchInput"));
+  if (!inject_touch_func) {
+    PLOG(INFO) << "Failed to get InjectTouchInput.";
+    return scoped_ptr<TouchInjectorWinDelegate>();
+  }
+
+  return scoped_ptr<TouchInjectorWinDelegate>(
+      new TouchInjectorWinDelegate(
+          library.Release(), init_func, inject_touch_func));
+}
+
+TouchInjectorWinDelegate::TouchInjectorWinDelegate(
+    base::NativeLibrary library,
+    InitializeTouchInjectionFunction initialize_touch_injection_func,
+    InjectTouchInputFunction inject_touch_input_func)
+    : library_module_(library),
+      initialize_touch_injection_func_(initialize_touch_injection_func),
+      inject_touch_input_func_(inject_touch_input_func) {}
+
+BOOL TouchInjectorWinDelegate::InitializeTouchInjection(UINT32 max_count,
+                                                        DWORD dw_mode) {
+  return initialize_touch_injection_func_(max_count, dw_mode);
+}
+
+DWORD TouchInjectorWinDelegate::InjectTouchInput(
+    UINT32 count,
+    const POINTER_TOUCH_INFO* contacts) {
+  return inject_touch_input_func_(count, contacts);
+}
+
+TouchInjectorWin::TouchInjectorWin()
+    : delegate_(TouchInjectorWinDelegate::Create()) {}
+
+TouchInjectorWin::~TouchInjectorWin() {}
+
+// Note that TouchInjectorWinDelegate::Create() is not called in this method
+// so that a mock delegate can be injected in tests and set expectations on the
+// mock and return value of this method.
+bool TouchInjectorWin::Init() {
+  if (!delegate_)
+    return false;
+
+  if (!delegate_->InitializeTouchInjection(
+          kMaxSimultaneousTouchCount, TOUCH_FEEDBACK_DEFAULT)) {
+    // delagate_ is reset here so that the function that need the delegate
+    // can check if it is null.
+    delegate_.reset();
+    PLOG(INFO) << "Failed to initialize touch injection.";
+    return false;
+  }
+
+  return true;
+}
+
+void TouchInjectorWin::Deinitialize() {
+  touches_in_contact_.clear();
+  // Same reason as TouchInjectorWin::Init(). For injecting mock delegates for
+  // tests, a new delegate is created here.
+  delegate_ = TouchInjectorWinDelegate::Create();
+}
+
+void TouchInjectorWin::InjectTouchEvent(const TouchEvent& event) {
+  if (!delegate_) {
+    VLOG(3) << "Touch injection functions are not initialized.";
+    return;
+  }
+
+  switch (event.event_type()) {
+    case TouchEvent::TOUCH_POINT_START:
+      AddNewTouchPoints(event);
+      break;
+    case TouchEvent::TOUCH_POINT_MOVE:
+      MoveTouchPoints(event);
+      break;
+    case TouchEvent::TOUCH_POINT_END:
+      EndTouchPoints(event);
+      break;
+    case TouchEvent::TOUCH_POINT_CANCEL:
+      CancelTouchPoints(event);
+      break;
+    default:
+      NOTREACHED();
+      return;
+  }
+}
+
+void TouchInjectorWin::SetInjectorDelegateForTest(
+    scoped_ptr<TouchInjectorWinDelegate> functions) {
+  delegate_ = functions.Pass();
+}
+
+void TouchInjectorWin::AddNewTouchPoints(const TouchEvent& event) {
+  DCHECK_EQ(event.event_type(), TouchEvent::TOUCH_POINT_START);
+
+  std::vector<POINTER_TOUCH_INFO> touches;
+  // Must inject already touching points as move events.
+  AppendMapValuesToVector(&touches_in_contact_, &touches);
+
+  for (const TouchEventPoint& touch_point : event.touch_points()) {
+    POINTER_TOUCH_INFO pointer_touch_info;
+    memset(&pointer_touch_info, 0, sizeof(pointer_touch_info));
+    pointer_touch_info.pointerInfo.pointerFlags =
+        POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT | POINTER_FLAG_DOWN;
+    ConvertToPointerTouchInfo(touch_point, &pointer_touch_info);
+    touches.push_back(pointer_touch_info);
+
+    // All points in the map should be a move point.
+    pointer_touch_info.pointerInfo.pointerFlags =
+        POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT | POINTER_FLAG_UPDATE;
+    touches_in_contact_[touch_point.id()] = pointer_touch_info;
+  }
+
+  if (delegate_->InjectTouchInput(touches.size(),
+                                  vector_as_array(&touches)) == 0) {
+    PLOG(ERROR) << "Failed to inject a touch start event.";
+  }
+}
+
+void TouchInjectorWin::MoveTouchPoints(const TouchEvent& event) {
+  DCHECK_EQ(event.event_type(), TouchEvent::TOUCH_POINT_MOVE);
+
+  for (const TouchEventPoint& touch_point : event.touch_points()) {
+    POINTER_TOUCH_INFO* pointer_touch_info =
+        &touches_in_contact_[touch_point.id()];
+    memset(pointer_touch_info, 0, sizeof(*pointer_touch_info));
+    pointer_touch_info->pointerInfo.pointerFlags =
+        POINTER_FLAG_INRANGE | POINTER_FLAG_INCONTACT | POINTER_FLAG_UPDATE;
+    ConvertToPointerTouchInfo(touch_point, pointer_touch_info);
+  }
+
+  std::vector<POINTER_TOUCH_INFO> touches;
+  // Must inject already touching points as move events.
+  AppendMapValuesToVector(&touches_in_contact_, &touches);
+  if (delegate_->InjectTouchInput(touches.size(),
+                                  vector_as_array(&touches)) == 0) {
+    PLOG(ERROR) << "Failed to inject a touch move event.";
+  }
+}
+
+void TouchInjectorWin::EndTouchPoints(const TouchEvent& event) {
+  DCHECK_EQ(event.event_type(), TouchEvent::TOUCH_POINT_END);
+
+  std::vector<POINTER_TOUCH_INFO> touches;
+  for (const TouchEventPoint& touch_point : event.touch_points()) {
+    POINTER_TOUCH_INFO pointer_touch_info =
+        touches_in_contact_[touch_point.id()];
+    pointer_touch_info.pointerInfo.pointerFlags = POINTER_FLAG_UP;
+
+    touches_in_contact_.erase(touch_point.id());
+    touches.push_back(pointer_touch_info);
+  }
+
+  AppendMapValuesToVector(&touches_in_contact_, &touches);
+  if (delegate_->InjectTouchInput(touches.size(),
+                                  vector_as_array(&touches)) == 0) {
+    PLOG(ERROR) << "Failed to inject a touch end event.";
+  }
+}
+
+void TouchInjectorWin::CancelTouchPoints(const TouchEvent& event) {
+  DCHECK_EQ(event.event_type(), TouchEvent::TOUCH_POINT_CANCEL);
+
+  std::vector<POINTER_TOUCH_INFO> touches;
+  for (const TouchEventPoint& touch_point : event.touch_points()) {
+    POINTER_TOUCH_INFO pointer_touch_info =
+        touches_in_contact_[touch_point.id()];
+    pointer_touch_info.pointerInfo.pointerFlags =
+        POINTER_FLAG_UP | POINTER_FLAG_CANCELED;
+
+    touches_in_contact_.erase(touch_point.id());
+    touches.push_back(pointer_touch_info);
+  }
+
+  AppendMapValuesToVector(&touches_in_contact_, &touches);
+  if (delegate_->InjectTouchInput(touches.size(),
+                                  vector_as_array(&touches)) == 0) {
+    PLOG(ERROR) << "Failed to inject a touch cancel event.";
+  }
+}
+
+}  // namespace remoting