Eager Gesture Recognizer (WIP)

ui/events/gestures/touch_point_state.cc

+// Copyright 2013 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 "ui/events/gestures/touch_point_state.h"
+
+#include "ui/events/event.h"
+#include "ui/events/event_constants.h"
+
+namespace ui {
+
+TouchPointState::TouchPointState(int touch_id)
+    : touch_id_(touch_id),
+      has_press_(false),
+      has_release_(false),
+      move_count_(0),
+      timer_count_(0) {
+}
+
+TouchPointState::TouchPointState(int touch_id,
+                                 bool has_press,
+                                 bool has_release,
+                                 int move_count,
+                                 int timer_count)
+    : touch_id_(touch_id),
+      has_press_(has_press),
+      has_release_(has_release),
+      move_count_(move_count),
+      timer_count_(timer_count) {
+}
+
+TouchPointState::~TouchPointState() {}
+
+void TouchPointState::Update(const TouchEvent& event) {
+  DCHECK(touch_id_ == event.touch_id());
+  switch(event.type()) {
+    case ET_TOUCH_PRESSED:
+      has_press_ = true;
+      break;
+    case ET_TOUCH_MOVED:
+    case ET_TOUCH_STATIONARY:
+      ++move_count_;
+      break;
+    case ET_TOUCH_RELEASED:
+    case ET_TOUCH_CANCELLED:
+      has_release_ = true;
+      break;
+    default:
+      // Should only be passed touch events.
+      NOTREACHED();
+  }
+}
+
+void TouchPointState::TimerFired() {
+  timer_count_++;
+}
+
+TouchPointState* TouchPointState::CopyForGestureType(
+    EventType type, RequiresAck requires_ack) const {
+  bool new_has_press = has_press_;
+  bool new_has_release = has_release_;
+  int new_move_count = move_count_;
+  int new_timer_count = 0;
+
+  switch(type) {
+    case ET_GESTURE_SHOW_PRESS:
+      // Only wait for show press timer.
+      new_timer_count = 1;
+      break;
+    case ET_GESTURE_LONG_PRESS:
+      // Wait for both long press and show press timers.
+      new_timer_count = 2;
+      break;
+    default:
+      break;
+  }
+
+  switch(type) {
+    case ET_GESTURE_SCROLL_BEGIN:
+    case ET_GESTURE_PINCH_BEGIN:
+    case ET_GESTURE_SCROLL_UPDATE:
+    case ET_GESTURE_PINCH_UPDATE:
+    case ET_GESTURE_SCROLL_END:
+    case ET_GESTURE_PINCH_END:
+    case ET_GESTURE_MULTIFINGER_SWIPE:
+    case ET_SCROLL_FLING_START:
+    case ET_SCROLL_FLING_CANCEL:
+      new_has_release = false;
+      break;
+    case ET_GESTURE_TAP:
+    case ET_GESTURE_LONG_TAP:
+    case ET_GESTURE_TWO_FINGER_TAP:
+      break;
+    case ET_GESTURE_BEGIN:
+    case ET_GESTURE_END:
+    case ET_GESTURE_SHOW_PRESS:
+    case ET_GESTURE_LONG_PRESS:
+    case ET_GESTURE_TAP_DOWN:
+    case ET_GESTURE_TAP_CANCEL:
+      new_has_release = false;
+      new_move_count = 0;
+      break;
+    default:
+      NOTREACHED() << "TouchPointState doesn't know about gesture type "
+                   << type;
+  }
+
+  if (requires_ack == NO_ACK) {
+    new_has_press = false;
+    new_has_release = false;
+    new_move_count = false;
+  }
+
+  return new TouchPointState(touch_id_,
+                             new_has_press,
+                             new_has_release,
+                             new_move_count,
+                             new_timer_count);
+}
+
+bool TouchPointState::HasEmptyIntersection(const TouchPointState& tps) const {
+  DCHECK(touch_id_ == tps.touch_id());
+  return Intersect(tps) == TouchPointState(touch_id_, 0, false, false, false);
+}
+
+bool TouchPointState::Contains(const TouchPointState& tps) const {
+  DCHECK(touch_id_ == tps.touch_id());
+  return Intersect(tps) == tps;
+}
+
+void TouchPointState::Reset() {
+  has_press_ = false;
+  has_release_ = false;
+  move_count_ = 0;
+  timer_count_ = 0;
+}
+
+TouchPointState::TouchPointState(const TouchPointState& tps)
+    : touch_id_(tps.touch_id()),
+      has_press_(tps.has_press()),
+      has_release_(tps.has_release()),
+      move_count_(tps.move_count()),
+      timer_count_(tps.timer_count()) {
+}
+
+TouchPointState TouchPointState::Intersect(const TouchPointState& tps) const {
+  DCHECK(touch_id_ == tps.touch_id());
+  return TouchPointState(
+      touch_id_,
+      has_press() && tps.has_press(),
+      has_release() && tps.has_release(),
+      std::min(move_count(), tps.move_count()),
+      std::min(timer_count(), tps.timer_count()));
+}
+
+}  // namespace ui