xref: /aosp_15_r20/external/libchrome-gestures/src/integral_gesture_filter_interpreter.cc (revision aed3e5085e770be5b69ce25295ecf6ddf906af95)
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 "include/integral_gesture_filter_interpreter.h"
6 
7 #include <math.h>
8 
9 #include "include/gestures.h"
10 #include "include/interpreter.h"
11 #include "include/logging.h"
12 #include "include/tracer.h"
13 
14 namespace gestures {
15 
16 // Takes ownership of |next|:
IntegralGestureFilterInterpreter(Interpreter * next,Tracer * tracer)17 IntegralGestureFilterInterpreter::IntegralGestureFilterInterpreter(
18     Interpreter* next, Tracer* tracer)
19     : FilterInterpreter(nullptr, next, tracer, false),
20       hscroll_remainder_(0.0),
21       vscroll_remainder_(0.0),
22       hscroll_ordinal_remainder_(0.0),
23       vscroll_ordinal_remainder_(0.0),
24       remainder_reset_deadline_(NO_DEADLINE) {
25   InitName();
26 }
27 
SyncInterpretImpl(HardwareState & hwstate,stime_t * timeout)28 void IntegralGestureFilterInterpreter::SyncInterpretImpl(
29     HardwareState& hwstate, stime_t* timeout) {
30   const char name[] = "IntegralGestureFilterInterpreter::SyncInterpretImpl";
31   LogHardwareStatePre(name, hwstate);
32 
33   can_clear_remainders_ = hwstate.finger_cnt == 0 && hwstate.touch_cnt == 0;
34   stime_t next_timeout = NO_DEADLINE;
35 
36   LogHardwareStatePost(name, hwstate);
37   next_->SyncInterpret(hwstate, &next_timeout);
38   *timeout = SetNextDeadlineAndReturnTimeoutVal(
39       hwstate.timestamp, remainder_reset_deadline_, next_timeout);
40 }
41 
HandleTimerImpl(stime_t now,stime_t * timeout)42 void IntegralGestureFilterInterpreter::HandleTimerImpl(
43     stime_t now, stime_t *timeout) {
44   const char name[] = "IntegralGestureFilterInterpreter::HandleTimerImpl";
45   LogHandleTimerPre(name, now, timeout);
46 
47   stime_t next_timeout;
48   if (ShouldCallNextTimer(remainder_reset_deadline_)) {
49     if (next_timer_deadline_ > now) {
50       Err("Spurious callback. now: %f, next deadline: %f",
51           now, next_timer_deadline_);
52       return;
53     }
54     next_timeout = NO_DEADLINE;
55     next_->HandleTimer(now, &next_timeout);
56   } else {
57     if (remainder_reset_deadline_ > now) {
58       Err("Spurious callback. now: %f, remainder reset deadline: %f",
59           now, remainder_reset_deadline_);
60       return;
61     }
62     if (can_clear_remainders_)
63       hscroll_ordinal_remainder_ = vscroll_ordinal_remainder_ =
64           hscroll_remainder_ = vscroll_remainder_ = 0.0;
65 
66     remainder_reset_deadline_ = NO_DEADLINE;
67     next_timeout = next_timer_deadline_ == NO_DEADLINE ||
68                    next_timer_deadline_ <= now
69                       ? NO_DEADLINE
70                       : next_timer_deadline_ - now;
71   }
72   *timeout = SetNextDeadlineAndReturnTimeoutVal(now,
73                                                 remainder_reset_deadline_,
74                                                 next_timeout);
75   LogHandleTimerPost(name, now, timeout);
76 }
77 
78 namespace {
Truncate(float input,float * overflow)79 float Truncate(float input, float* overflow) {
80   input += *overflow;
81   float input_ret = truncf(input);
82   *overflow = input - input_ret;
83   return input_ret;
84 }
85 }  // namespace {}
86 
87 // Truncate the fractional part off any input, but store it. If the
88 // absolute value of an input is < 1, we will change it to 0, unless
89 // there has been enough fractional accumulation to bring it above 1.
ConsumeGesture(const Gesture & gesture)90 void IntegralGestureFilterInterpreter::ConsumeGesture(const Gesture& gesture) {
91   const char name[] = "IntegralGestureFilterInterpreter::ConsumeGesture";
92   LogGestureConsume(name, gesture);
93 
94   Gesture copy = gesture;
95   switch (gesture.type) {
96     case kGestureTypeMove:
97       if (gesture.details.move.dx != 0.0 || gesture.details.move.dy != 0.0 ||
98           gesture.details.move.ordinal_dx != 0.0 ||
99           gesture.details.move.ordinal_dy != 0.0) {
100         LogGestureProduce(name, gesture);
101         ProduceGesture(gesture);
102       }
103       break;
104     case kGestureTypeScroll:
105       copy.details.scroll.dx = Truncate(copy.details.scroll.dx,
106                                         &hscroll_remainder_);
107       copy.details.scroll.dy = Truncate(copy.details.scroll.dy,
108                                         &vscroll_remainder_);
109       copy.details.scroll.ordinal_dx = Truncate(copy.details.scroll.ordinal_dx,
110                                                 &hscroll_ordinal_remainder_);
111       copy.details.scroll.ordinal_dy = Truncate(copy.details.scroll.ordinal_dy,
112                                                 &vscroll_ordinal_remainder_);
113       if (copy.details.scroll.dx != 0.0 || copy.details.scroll.dy != 0.0 ||
114           copy.details.scroll.ordinal_dx != 0.0 ||
115           copy.details.scroll.ordinal_dy != 0.0) {
116         LogGestureProduce(name, copy);
117         ProduceGesture(copy);
118       } else if (copy.details.scroll.stop_fling) {
119         auto fling_tap_down = Gesture(kGestureFling,
120                                       copy.start_time, copy.end_time,
121                                       0, 0, GESTURES_FLING_TAP_DOWN);
122         LogGestureProduce(name, fling_tap_down);
123         ProduceGesture(fling_tap_down);
124       }
125       remainder_reset_deadline_ = copy.end_time + 1.0;
126       break;
127     case kGestureTypeMouseWheel:
128       copy.details.wheel.dx = Truncate(copy.details.wheel.dx,
129                                        &hscroll_remainder_);
130       copy.details.wheel.dy = Truncate(copy.details.wheel.dy,
131                                        &vscroll_remainder_);
132       if (copy.details.wheel.dx != 0.0 || copy.details.wheel.dy != 0.0 ||
133           copy.details.wheel.tick_120ths_dx != 0.0 ||
134           copy.details.wheel.tick_120ths_dy != 0.0) {
135         LogGestureProduce(name, copy);
136         ProduceGesture(copy);
137       }
138       remainder_reset_deadline_ = copy.end_time + 1.0;
139       break;
140     default:
141       LogGestureProduce(name, gesture);
142       ProduceGesture(gesture);
143       break;
144   }
145 }
146 
147 }  // namespace gestures
148