• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright 2012 The ChromiumOS Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include <map>
6 #include <set>
7 
8 #include <gtest/gtest.h>  // for FRIEND_TEST
9 
10 #include "include/filter_interpreter.h"
11 #include "include/finger_metrics.h"
12 #include "include/gestures.h"
13 #include "include/macros.h"
14 #include "include/tracer.h"
15 
16 #ifndef GESTURES_PALM_CLASSIFYING_FILTER_INTERPRETER_H_
17 #define GESTURES_PALM_CLASSIFYING_FILTER_INTERPRETER_H_
18 
19 namespace gestures {
20 
21 // This interpreter looks at the location and pressure of contacts and may
22 // optionally classify each as a palm. Sometimes a contact is classified as
23 // a palm in some frames, and then in subsequent frames it is not.
24 // This interpreter is also used to suppress motion from thumbs in the
25 // bottom area of the pad.
26 
27 class PalmClassifyingFilterInterpreter : public FilterInterpreter {
28   FRIEND_TEST(PalmClassifyingFilterInterpreterTest, PalmAtEdgeTest);
29   FRIEND_TEST(PalmClassifyingFilterInterpreterTest, PalmReevaluateTest);
30   FRIEND_TEST(PalmClassifyingFilterInterpreterTest, PalmTest);
31   FRIEND_TEST(PalmClassifyingFilterInterpreterTest, StationaryPalmTest);
32  public:
33   // Takes ownership of |next|:
34   PalmClassifyingFilterInterpreter(PropRegistry* prop_reg, Interpreter* next,
35                                    Tracer* tracer);
~PalmClassifyingFilterInterpreter()36   virtual ~PalmClassifyingFilterInterpreter() {}
37 
38  protected:
39   virtual void SyncInterpretImpl(HardwareState* hwstate, stime_t* timeout);
40 
41  private:
42   void FillOriginInfo(const HardwareState& hwstate);
43   void FillPrevInfo(const HardwareState& hwstate);
44   void FillMaxPressureWidthInfo(const HardwareState& hwstate);
45 
46   // Part of palm detection. Returns true if the finger indicated by
47   // |finger_idx| is near another finger, which must not be a palm, in the
48   // hwstate.
49   bool FingerNearOtherFinger(const HardwareState& hwstate,
50                              size_t finger_idx);
51 
52   // Returns true iff fs represents a contact that may be a palm. It's a palm
53   // if it's in the side edge (or top edge if filter_top_edge_ is set) with
54   // sufficiently large pressure. The pressure required depends on exactly how
55   // close to the edge the contact is.
56   bool FingerInPalmEnvelope(const FingerState& fs);
57 
58   // Returns true iff fs represents a contact that is in the bottom area.
59   bool FingerInBottomArea(const FingerState& fs);
60 
61   // Updates *palm_, pointing_ below.
62   void UpdatePalmState(const HardwareState& hwstate);
63 
64   // Updates the hwstate based on the local state.
65   void UpdatePalmFlags(HardwareState* hwstate);
66 
67   // Updates the distance travelled for each finger along +- x/y direction.
68   void UpdateDistanceInfo(const HardwareState& hwstate);
69 
70   // Returns the length of time the contact has been on the pad. Returns -1
71   // on error.
72   stime_t FingerAge(short finger_id, stime_t now) const;
73 
74   // Time when a contact arrived. Persists even when fingers change.
75   std::map<short, stime_t> origin_timestamps_;
76   // FingerStates from when a contact first arrived. Persists even when fingers
77   // change.
78   std::map<short, FingerState> origin_fingerstates_;
79 
80   // FingerStates from the previous HardwareState.
81   std::map<short, FingerState> prev_fingerstates_;
82 
83   // Max reported pressure for present fingers.
84   std::map<short, float> max_pressure_;
85 
86   // Max reported width for present fingers.
87   std::map<short, float> max_width_;
88 
89   // Accumulated distance travelled by each finger.
90   // _positive[0]  -->  positive direction along x axis
91   // _positive[1]  -->  positive direction along y axis
92   // _negative[0]  -->  negative direction along x axis
93   // _negative[1]  -->  negative direction along y axis
94   std::map<short, float> distance_positive_[2];
95   std::map<short, float> distance_negative_[2];
96 
97   // Same fingers state. This state is accumulated as fingers remain the same
98   // and it's reset when fingers change.
99   std::set<short> palm_;  // tracking ids of known palms
100   // These contacts are a subset of palms_ which are marked as palms because
101   // they have a large contact size.
102   std::set<short> large_palm_;
103   // These contacts have moved significantly and shouldn't be considered
104   // stationary palms:
105   std::set<short> non_stationary_palm_;
106 
107   static const unsigned kPointCloseToFinger = 1;
108   static const unsigned kPointNotInEdge = 2;
109   static const unsigned kPointMoving = 4;
110   // tracking ids of known fingers that are not palms, along with the reason(s)
111   std::map<short, unsigned> pointing_;
112 
113 
114   // tracking ids that were ever close to other fingers.
115   std::set<short> was_near_other_fingers_;
116 
117   // tracking ids that have ever travelled out of the palm envelope or bottom
118   // area.
119   std::set<short> fingers_not_in_edge_;
120 
121   // Previously input timestamp
122   stime_t prev_time_;
123 
124   // Maximum pressure above which a finger is considered a palm
125   DoubleProperty palm_pressure_;
126   // Maximum width_major above which a finger is considered a palm
127   DoubleProperty palm_width_;
128   // Maximum width_major above which a finger is considered a palm if there are
129   // other contacts
130   DoubleProperty multi_palm_width_;
131   // If a finger was previously classified as palm, but its lifetime max
132   // pressure is less than palm_pressure_ * fat_finger_pressure_ratio_,
133   // lifetime max width is less than palm_width_ * fat_finger_width_ratio_,
134   // and has moved more than fat_finger_min_dist_, we consider it as a fat
135   // finger.
136   DoubleProperty fat_finger_pressure_ratio_;
137   DoubleProperty fat_finger_width_ratio_;
138   DoubleProperty fat_finger_min_dist_;
139   // The smaller of two widths around the edge for palm detection. Any contact
140   // in this edge zone may be a palm, regardless of pressure
141   DoubleProperty palm_edge_min_width_;
142   // The larger of the two widths. Palms between this and the previous are
143   // expected to have pressure linearly increase from 0 to palm_pressure_
144   // as they approach this border.
145   DoubleProperty palm_edge_width_;
146   // If filter_top_edge_ is set, any contact this close to the top edge may be
147   // a palm.
148   DoubleProperty palm_top_edge_min_width_;
149   // Palms in edge are allowed to point if they move fast enough
150   DoubleProperty palm_edge_point_speed_;
151   // A finger can be added to the palm envelope (and thus not point) after
152   // it touches down and until palm_eval_timeout_ [s] time.
153   DoubleProperty palm_eval_timeout_;
154   // A potential palm (ambiguous contact in the edge of the pad) will be marked
155   // a palm if it travels less than palm_stationary_distance_ mm after it's
156   // been on the pad for palm_stationary_time_ seconds.
157   DoubleProperty palm_stationary_time_;
158   DoubleProperty palm_stationary_distance_;
159   // For a finger in the palm envelope to be qualified as pointing, it has to
160   // move in one direction at least palm_pointing_min_dist_ and no more
161   // than palm_pointing_max_reverse_dist_ in the opposite direction.
162   DoubleProperty palm_pointing_min_dist_;
163   DoubleProperty palm_pointing_max_reverse_dist_;
164   // If a palm splits right on the edge, sometimes the pressure readings aren't
165   // high enough to identify the palm.  If two fingers on the edge of the pad
166   // are closer together than this value, then they are likely a split palm.
167   DoubleProperty palm_split_max_distance_;
168   // Determines whether we look for palms at the top edge of the touchpad.
169   BoolProperty filter_top_edge_;
170 
171   DISALLOW_COPY_AND_ASSIGN(PalmClassifyingFilterInterpreter);
172 };
173 
174 }  // namespace gestures
175 
176 #endif  // GESTURES_PALM_CLASSIFYING_FILTER_INTERPRETER_H_
177