Merge CMTEventData and ValuatorTracker

The patch merges the CMTEventData class in event_x.cc with the ValuatorTracker
class into an unified class DeviceDataManager that deals with all X valuator
data extraction tasks. It provides new APIs for checking X event types,
extracting values from X valuators and more. It currently handles mouses,
touchpads and touchscreens.

Contributed by sheckylin@chromium.org

BUG=244253
TEST=Tested on device.

Change-Id: I19208c876a4da6865a86a540bff36db32997bfe0

Review URL: https://chromiumcodereview.appspot.com/15705004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@206336 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 238 insertions, 0 deletions

diff --git a/ui/base/x/device_data_manager.h b/ui/base/x/device_data_manager.h
new file mode 100644
index 0000000..27f468a
--- /dev/null
+++ b/ui/base/x/device_data_manager.h
@@ -0,0 +1,238 @@
+// 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.
+
+#ifndef UI_BASE_X_DEVICE_DATA_MANAGER_H_
+#define UI_BASE_X_DEVICE_DATA_MANAGER_H_
+
+#include <X11/extensions/XInput2.h>
+
+#include <bitset>
+#include <map>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/event_types.h"
+#include "ui/base/events/event_constants.h"
+#include "ui/base/ui_export.h"
+#include "ui/base/x/x11_atom_cache.h"
+
+template <typename T> struct DefaultSingletonTraits;
+
+typedef union _XEvent XEvent;
+
+namespace ui {
+
+// A class that extracts and tracks the input events data. It currently handles
+// mouse, touchpad and touchscreen devices.
+class UI_EXPORT DeviceDataManager {
+ public:
+  // Enumerate additional data that one might be interested on an input event,
+  // which are usually wrapped in X valuators. If you modify any of this,
+  // make sure to update the kCachedAtoms data structure in the source file
+  // and the k*Type[Start/End] constants used by IsCMTDataType and
+  // IsTouchDataType.
+  enum DataType {
+    // Define the valuators used the CrOS CMT driver. Used by mice and CrOS
+    // touchpads.
+    DT_CMT_SCROLL_X = 0,  // Scroll amount on the X (horizontal) direction.
+    DT_CMT_SCROLL_Y,      // Scroll amount on the Y (vertical) direction.
+    DT_CMT_ORDINAL_X,     // Original (unaccelerated) value on the X direction.
+                          // Can be used both for scrolls and flings.
+    DT_CMT_ORDINAL_Y,     // Original (unaccelerated) value on the Y direction.
+                          // Can be used both for scrolls and flings.
+    DT_CMT_START_TIME,    // Gesture start time.
+    DT_CMT_END_TIME,      // Gesture end time.
+    DT_CMT_FLING_X,       // Fling amount on the X (horizontal) direction.
+    DT_CMT_FLING_Y,       // Fling amount on the Y (vertical) direction.
+    DT_CMT_FLING_STATE,   // The state of fling gesture (whether the user just
+                          // start flinging or that he/she taps down).
+    DT_CMT_FINGER_COUNT,  // Finger counts in the current gesture. A same type
+                          // of gesture can have very different meanings based
+                          // on that (e.g. 2f scroll v.s. 3f swipe).
+
+    // End of CMT data types.
+    // Beginning of touch data types.
+
+    // Define the valuators following the Multi-touch Protocol. Used by
+    // touchscreen devices.
+    DT_TOUCH_MAJOR,       // Length of the touch area.
+    DT_TOUCH_MINOR,       // Width of the touch area.
+    DT_TOUCH_ORIENTATION, // Angle between the X-axis and the major axis of the
+                          // touch area.
+    DT_TOUCH_PRESSURE,    // Pressure of the touch contact.
+
+    // NOTE: A touch event can have multiple touch points. So when we receive a
+    // touch event, we need to determine which point triggered the event.
+    // A touch point can have both a 'Slot ID' and a 'Tracking ID', and they can
+    // be (in fact, usually are) different. The 'Slot ID' ranges between 0 and
+    // (X - 1), where X is the maximum touch points supported by the device. The
+    // 'Tracking ID' can be any 16-bit value. With XInput 2.0, an XI_Motion
+    // event that comes from a currently-unused 'Slot ID' indicates the creation
+    // of a new touch point, and any event that comes with a 0 value for
+    // 'Tracking ID' marks the removal of a touch point. During the lifetime of
+    // a touchpoint, we use the 'Slot ID' as its identifier. The XI_ButtonPress
+    // and XI_ButtonRelease events are ignored.
+#if !defined(USE_XI2_MT)
+    DT_TOUCH_SLOT_ID,     // ID of the finger that triggered a touch event
+                          // (useful when tracking multiple simultaneous
+                          // touches).
+#endif
+    // NOTE for XInput MT: 'Tracking ID' is provided in every touch event to
+    // track individual touch. 'Tracking ID' is an unsigned 32-bit value and
+    // is increased for each new touch. It will wrap back to 0 when reaching
+    // the numerical limit.
+    DT_TOUCH_TRACKING_ID, // ID of the touch point.
+
+    // Kernel timestamp from touch screen (if available).
+    DT_TOUCH_RAW_TIMESTAMP,
+
+    // End of touch data types.
+
+    DT_LAST_ENTRY         // This must come last.
+  };
+
+  // Data struct to store extracted data from an input event.
+  typedef std::map<int, double> EventData;
+
+  // We use int because enums can be casted to ints but not vice versa.
+  static bool IsCMTDataType(const int type);
+  static bool IsTouchDataType(const int type);
+
+  // Returns the DeviceDataManager singleton.
+  static DeviceDataManager* GetInstance();
+
+  // Natural scroll setter/getter.
+  bool natural_scroll_enabled() const { return natural_scroll_enabled_; }
+  void set_natural_scroll_enabled(bool enabled) {
+    natural_scroll_enabled_ = enabled;
+  }
+
+  // Get the natural scroll direction multiplier (1.0f or -1.0f).
+  float GetNaturalScrollFactor(int sourceid) const;
+
+  // Updates the list of devices.
+  void UpdateDeviceList(Display* display);
+
+  // Get all event data in one pass. We extract only data types that we know
+  // about (defined in enum DataType). The data is not processed (e.g. not
+  // filled in by cached values) as in GetEventData.
+  void GetEventRawData(const XEvent& xev, EventData* data);
+
+  // Get a datum of the specified type. Return true and the value
+  // is updated if the data is found, false and value unchanged if the data is
+  // not found. In the case of MT-B/XI2.2, the value can come from a previously
+  // cached one (see the comment above last_seen_valuator_).
+  bool GetEventData(const XEvent& xev, const DataType type, double* value);
+
+  // Check if the event comes from touchpad devices.
+  bool IsTouchpadXInputEvent(const base::NativeEvent& native_event) const;
+
+  // Check if the event comes from devices running CMT driver or using
+  // CMT valuators (e.g. mouses). Note that doesn't necessarily mean the event
+  // is a CMT event (e.g. it could be a mouse pointer move).
+  bool IsCMTDeviceEvent(const base::NativeEvent& native_event) const;
+
+  // Check if the event is one of the CMT gesture events (scroll, fling,
+  // metrics etc.).
+  bool IsCMTGestureEvent(const base::NativeEvent& native_event) const;
+
+  // Returns true if the event is of the specific type, false if not.
+  bool IsScrollEvent(const base::NativeEvent& native_event) const;
+  bool IsFlingEvent(const base::NativeEvent& native_event) const;
+
+  // Returns true if the event has CMT start/end timestamps.
+  bool HasGestureTimes(const base::NativeEvent& native_event) const;
+
+  // Extract data from a scroll event (a motion event with the necessary
+  // valuators). User must first verify the event type with IsScrollEvent.
+  // Pointers shouldn't be NULL.
+  void GetScrollOffsets(const base::NativeEvent& native_event,
+                        float* x_offset,
+                        float* y_offset,
+                        float* x_offset_ordinal,
+                        float* y_offset_ordinal,
+                        int* finger_count);
+
+  // Extract data from a fling event. User must first verify the event type
+  // with IsFlingEvent. Pointers shouldn't be NULL.
+  void GetFlingData(const base::NativeEvent& native_event,
+                    float* vx,
+                    float* vy,
+                    float* vx_ordinal,
+                    float* vy_ordinal,
+                    bool* is_cancel);
+
+  // Extract the start/end timestamps from CMT events. User must first verify
+  // the event with HasGestureTimes. Pointers shouldn't be NULL.
+  void GetGestureTimes(const base::NativeEvent& native_event,
+                       double* start_time,
+                       double* end_time);
+
+  // Normalize the data value on deviceid to fall into [0, 1].
+  // *value = (*value - min_value_of_tp) / (max_value_of_tp - min_value_of_tp)
+  // Returns true and sets the normalized value in|value| if normalization is
+  // successful. Returns false and |value| is unchanged otherwise.
+  bool NormalizeData(unsigned int deviceid,
+                     const DataType type,
+                     double* value);
+
+  // Extract the range of the data type. Return true if the range is available
+  // and written into min & max, false if the range is not available.
+  bool GetDataRange(unsigned int deviceid,
+                    const DataType type,
+                    double* min,
+                    double* max);
+
+ private:
+  // Requirement for Singleton.
+  friend struct DefaultSingletonTraits<DeviceDataManager>;
+
+  DeviceDataManager();
+  ~DeviceDataManager();
+
+  // Check if an XI event contains data of the specified type.
+  bool HasEventData(const XIDeviceEvent* xiev, const DataType type) const;
+
+  static const int kMaxDeviceNum = 128;
+  bool natural_scroll_enabled_;
+
+  // A quick lookup table for determining if events from the pointer device
+  // should be processed.
+  std::bitset<kMaxDeviceNum> cmt_devices_;
+  std::bitset<kMaxDeviceNum> touchpads_;
+
+  // Number of valuators on the specific device.
+  int valuator_count_[kMaxDeviceNum];
+
+  // Index table to find the valuator for DataType on the specific device
+  // by valuator_lookup_[device_id][data_type].
+  std::vector<int> valuator_lookup_[kMaxDeviceNum];
+
+  // Index table to find the DataType for valuator on the specific device
+  // by data_type_lookup_[device_id][valuator].
+  std::vector<int> data_type_lookup_[kMaxDeviceNum];
+
+  // Index table to find the min & max value of the Valuator on a specific
+  // device.
+  std::vector<double> valuator_min_[kMaxDeviceNum];
+  std::vector<double> valuator_max_[kMaxDeviceNum];
+
+  // Table to keep track of the last seen value for the specified valuator for
+  // a device. Defaults to 0 if the valuator was not specified in an earlier
+  // event. With MT-B/XI2.2, valuators in an XEvent are not reported if the
+  // values haven't changed from the previous event. So it is necessary to
+  // remember these valuators so that chrome doesn't think X/device doesn't
+  // know about the valuators. We currently use this only on touchscreen
+  // devices.
+  std::vector<double> last_seen_valuator_[kMaxDeviceNum];
+
+  // X11 atoms cache.
+  X11AtomCache atom_cache_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceDataManager);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_X_DEVICE_DATA_MANAGER_H_