ui/events/gestures/motion_event_aura.cc

   1 // Copyright 2014 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 // MSVC++ requires this to be set before any other includes to get M_PI.
   6 #define _USE_MATH_DEFINES
   7
   8 #include "ui/events/gestures/motion_event_aura.h"
   9
  10 #include <cmath>
  11
  12 #include "base/logging.h"
  13 #include "ui/events/gesture_detection/gesture_configuration.h"
  14
  15 namespace ui {
  16 namespace {
  17
  18 PointerProperties GetPointerPropertiesFromTouchEvent(const TouchEvent& touch) {
  19   PointerProperties pointer_properties;
  20   pointer_properties.x = touch.x();
  21   pointer_properties.y = touch.y();
  22   pointer_properties.raw_x = touch.root_location_f().x();
  23   pointer_properties.raw_y = touch.root_location_f().y();
  24   pointer_properties.id = touch.touch_id();
  25   pointer_properties.pressure = touch.force();
  26   pointer_properties.source_device_id = touch.source_device_id();
  27
  28   float radius_x = touch.radius_x();
  29   float radius_y = touch.radius_y();
  30   float rotation_angle_rad = touch.rotation_angle() * M_PI / 180.f;
  31   DCHECK_GE(radius_x, 0) << "Unexpected x-radius < 0";
  32   DCHECK_GE(radius_y, 0) << "Unexpected y-radius < 0";
  33   DCHECK(0 <= rotation_angle_rad && rotation_angle_rad <= M_PI_2)
  34       << "Unexpected touch rotation angle";
  35
  36   if (radius_x > radius_y) {
  37     // The case radius_x == radius_y is omitted from here on purpose: for
  38     // circles, we want to pass the angle (which could be any value in such
  39     // cases but always seem to be set to zero) unchanged.
  40     pointer_properties.touch_major = 2.f * radius_x;
  41     pointer_properties.touch_minor = 2.f * radius_y;
  42     pointer_properties.orientation = rotation_angle_rad - M_PI_2;
  43   } else {
  44     pointer_properties.touch_major = 2.f * radius_y;
  45     pointer_properties.touch_minor = 2.f * radius_x;
  46     pointer_properties.orientation = rotation_angle_rad;
  47   }
  48
  49   if (!pointer_properties.touch_major) {
  50     pointer_properties.touch_major =
  51         2.f * GestureConfiguration::GetInstance()->default_radius();
  52     pointer_properties.touch_minor =
  53         2.f * GestureConfiguration::GetInstance()->default_radius();
  54     pointer_properties.orientation = 0;
  55   }
  56
  57   // TODO(jdduke): Plumb tool type from the platform, crbug.com/404128.
  58   pointer_properties.tool_type = MotionEvent::TOOL_TYPE_UNKNOWN;
  59
  60   return pointer_properties;
  61 }
  62
  63 }  // namespace
  64
  65 MotionEventAura::MotionEventAura() {
  66   set_action_index(-1);
  67 }
  68
  69 MotionEventAura::~MotionEventAura() {
  70 }
  71
  72 bool MotionEventAura::OnTouch(const TouchEvent& touch) {
  73   int index = FindPointerIndexOfId(touch.touch_id());
  74   bool pointer_id_is_active = index != -1;
  75
  76   if (touch.type() == ET_TOUCH_PRESSED && pointer_id_is_active) {
  77     // Ignore touch press events if we already believe the pointer is down.
  78
  79     // TODO(tdresser): this should return false (or NOTREACHED());
  80     // however, there is at least one case where we need to allow a
  81     // touch press from a currently used touch id. See
  82     // crbug.com/446852 for details.
  83   } else if (touch.type() != ET_TOUCH_PRESSED && !pointer_id_is_active) {
  84     // We could have an active touch stream transfered to us, resulting in touch
  85     // move or touch up events without associated touch down events. Ignore
  86     // them.
  87     return false;
  88   }
  89
  90   if (touch.type() == ET_TOUCH_MOVED && touch.x() == GetX(index) &&
  91       touch.y() == GetY(index)) {
  92     return false;
  93   }
  94
  95   switch (touch.type()) {
  96     case ET_TOUCH_PRESSED:
  97       AddTouch(touch);
  98       break;
  99     case ET_TOUCH_RELEASED:
 100     case ET_TOUCH_CANCELLED:
 101       // Removing these touch points needs to be postponed until after the
 102       // MotionEvent has been dispatched. This cleanup occurs in
 103       // CleanupRemovedTouchPoints.
 104       UpdateTouch(touch);
 105       break;
 106     case ET_TOUCH_MOVED:
 107       UpdateTouch(touch);
 108       break;
 109     default:
 110       NOTREACHED();
 111       return false;
 112   }
 113
 114   UpdateCachedAction(touch);
 115   set_flags(touch.flags());
 116   set_event_time(touch.time_stamp() + base::TimeTicks());
 117   return true;
 118 }
 119
 120 int MotionEventAura::GetId() const {
 121   return GetPointerId(0);
 122 }
 123
 124 void MotionEventAura::CleanupRemovedTouchPoints(const TouchEvent& event) {
 125   if (event.type() != ET_TOUCH_RELEASED &&
 126       event.type() != ET_TOUCH_CANCELLED) {
 127     return;
 128   }
 129
 130   DCHECK(GetPointerCount());
 131   int index_to_delete = GetIndexFromId(event.touch_id());
 132   set_action_index(0);
 133   pointer(index_to_delete) = pointer(GetPointerCount() - 1);
 134   PopPointer();
 135 }
 136
 137 int MotionEventAura::GetSourceDeviceId(size_t pointer_index) const {
 138   DCHECK_LT(pointer_index, GetPointerCount());
 139   return pointer(pointer_index).source_device_id;
 140 }
 141
 142 void MotionEventAura::AddTouch(const TouchEvent& touch) {
 143   if (GetPointerCount() == MotionEvent::MAX_TOUCH_POINT_COUNT)
 144     return;
 145
 146   PushPointer(GetPointerPropertiesFromTouchEvent(touch));
 147 }
 148
 149 void MotionEventAura::UpdateTouch(const TouchEvent& touch) {
 150   pointer(GetIndexFromId(touch.touch_id())) =
 151       GetPointerPropertiesFromTouchEvent(touch);
 152 }
 153
 154 void MotionEventAura::UpdateCachedAction(const TouchEvent& touch) {
 155   DCHECK(GetPointerCount());
 156   switch (touch.type()) {
 157     case ET_TOUCH_PRESSED:
 158       if (GetPointerCount() == 1) {
 159         set_action(ACTION_DOWN);
 160       } else {
 161         set_action(ACTION_POINTER_DOWN);
 162         set_action_index(GetIndexFromId(touch.touch_id()));
 163       }
 164       break;
 165     case ET_TOUCH_RELEASED:
 166       if (GetPointerCount() == 1) {
 167         set_action(ACTION_UP);
 168       } else {
 169         set_action(ACTION_POINTER_UP);
 170         set_action_index(GetIndexFromId(touch.touch_id()));
 171       }
 172       break;
 173     case ET_TOUCH_CANCELLED:
 174       set_action(ACTION_CANCEL);
 175       break;
 176     case ET_TOUCH_MOVED:
 177       set_action(ACTION_MOVE);
 178       break;
 179     default:
 180       NOTREACHED();
 181       break;
 182   }
 183 }
 184
 185 int MotionEventAura::GetIndexFromId(int id) const {
 186   int index = FindPointerIndexOfId(id);
 187   DCHECK_GE(index, 0);
 188   DCHECK_LT(index, static_cast<int>(GetPointerCount()));
 189   return index;
 190 }
 191
 192 }  // namespace ui