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(NULL, 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 can_clear_remainders_ = hwstate->finger_cnt == 0 && hwstate->touch_cnt == 0;
31 stime_t next_timeout = NO_DEADLINE;
32 next_->SyncInterpret(hwstate, &next_timeout);
33 *timeout = SetNextDeadlineAndReturnTimeoutVal(
34 hwstate->timestamp, remainder_reset_deadline_, next_timeout);
35 }
36
HandleTimerImpl(stime_t now,stime_t * timeout)37 void IntegralGestureFilterInterpreter::HandleTimerImpl(
38 stime_t now, stime_t *timeout) {
39 if (ShouldCallNextTimer(remainder_reset_deadline_)) {
40 if (next_timer_deadline_ > now) {
41 Err("Spurious callback. now: %f, next deadline: %f",
42 now, next_timer_deadline_);
43 return;
44 }
45
46 stime_t next_timeout = NO_DEADLINE;
47 next_->HandleTimer(now, &next_timeout);
48 *timeout = SetNextDeadlineAndReturnTimeoutVal(now,
49 remainder_reset_deadline_,
50 next_timeout);
51 } else {
52 if (remainder_reset_deadline_ > now) {
53 Err("Spurious callback. now: %f, remainder reset deadline: %f",
54 now, remainder_reset_deadline_);
55 return;
56 }
57 if (can_clear_remainders_)
58 hscroll_ordinal_remainder_ = vscroll_ordinal_remainder_ =
59 hscroll_remainder_ = vscroll_remainder_ = 0.0;
60
61 remainder_reset_deadline_ = NO_DEADLINE;
62 stime_t next_timeout =
63 next_timer_deadline_ == NO_DEADLINE || next_timer_deadline_ <= now ?
64 NO_DEADLINE : next_timer_deadline_ - now;
65 *timeout = SetNextDeadlineAndReturnTimeoutVal(now,
66 remainder_reset_deadline_,
67 next_timeout);
68 }
69 }
70
71 namespace {
Truncate(float input,float * overflow)72 float Truncate(float input, float* overflow) {
73 input += *overflow;
74 float input_ret = truncf(input);
75 *overflow = input - input_ret;
76 return input_ret;
77 }
78 } // namespace {}
79
80 // Truncate the fractional part off any input, but store it. If the
81 // absolute value of an input is < 1, we will change it to 0, unless
82 // there has been enough fractional accumulation to bring it above 1.
ConsumeGesture(const Gesture & gesture)83 void IntegralGestureFilterInterpreter::ConsumeGesture(const Gesture& gesture) {
84 Gesture copy = gesture;
85 switch (gesture.type) {
86 case kGestureTypeMove:
87 if (gesture.details.move.dx != 0.0 || gesture.details.move.dy != 0.0 ||
88 gesture.details.move.ordinal_dx != 0.0 ||
89 gesture.details.move.ordinal_dy != 0.0)
90 ProduceGesture(gesture);
91 break;
92 case kGestureTypeScroll:
93 copy.details.scroll.dx = Truncate(copy.details.scroll.dx,
94 &hscroll_remainder_);
95 copy.details.scroll.dy = Truncate(copy.details.scroll.dy,
96 &vscroll_remainder_);
97 copy.details.scroll.ordinal_dx = Truncate(copy.details.scroll.ordinal_dx,
98 &hscroll_ordinal_remainder_);
99 copy.details.scroll.ordinal_dy = Truncate(copy.details.scroll.ordinal_dy,
100 &vscroll_ordinal_remainder_);
101 if (copy.details.scroll.dx != 0.0 || copy.details.scroll.dy != 0.0 ||
102 copy.details.scroll.ordinal_dx != 0.0 ||
103 copy.details.scroll.ordinal_dy != 0.0) {
104 ProduceGesture(copy);
105 } else if (copy.details.scroll.stop_fling) {
106 ProduceGesture(Gesture(kGestureFling, copy.start_time, copy.end_time,
107 0, 0, GESTURES_FLING_TAP_DOWN));
108 }
109 remainder_reset_deadline_ = copy.end_time + 1.0;
110 break;
111 case kGestureTypeMouseWheel:
112 copy.details.wheel.dx = Truncate(copy.details.wheel.dx,
113 &hscroll_remainder_);
114 copy.details.wheel.dy = Truncate(copy.details.wheel.dy,
115 &vscroll_remainder_);
116 if (copy.details.wheel.dx != 0.0 || copy.details.wheel.dy != 0.0 ||
117 copy.details.wheel.tick_120ths_dx != 0.0 ||
118 copy.details.wheel.tick_120ths_dy != 0.0) {
119 ProduceGesture(copy);
120 }
121 remainder_reset_deadline_ = copy.end_time + 1.0;
122 break;
123 default:
124 ProduceGesture(gesture);
125 break;
126 }
127 }
128
129 } // namespace gestures
130