1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
|
// Copyright 2020 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included
#include "common/math_util.h"
#include "input_common/motion_input.h"
namespace InputCommon {
MotionInput::MotionInput(f32 new_kp, f32 new_ki, f32 new_kd)
: kp(new_kp), ki(new_ki), kd(new_kd), quat{{0, 0, -1}, 0} {}
void MotionInput::SetAcceleration(const Common::Vec3f& acceleration) {
accel = acceleration;
}
void MotionInput::SetGyroscope(const Common::Vec3f& gyroscope) {
gyro = gyroscope - gyro_drift;
if (gyro.Length2() < gyro_threshold) {
gyro = {};
}
}
void MotionInput::SetQuaternion(const Common::Quaternion<f32>& quaternion) {
quat = quaternion;
}
void MotionInput::SetGyroDrift(const Common::Vec3f& drift) {
gyro_drift = drift;
}
void MotionInput::SetGyroThreshold(f32 threshold) {
gyro_threshold = threshold;
}
void MotionInput::EnableReset(bool reset) {
reset_enabled = reset;
}
void MotionInput::ResetRotations() {
rotations = {};
}
bool MotionInput::IsMoving(f32 sensitivity) const {
return gyro.Length() >= sensitivity || accel.Length() <= 0.9f || accel.Length() >= 1.1f;
}
bool MotionInput::IsCalibrated(f32 sensitivity) const {
return real_error.Length() < sensitivity;
}
void MotionInput::UpdateRotation(u64 elapsed_time) {
const f32 sample_period = elapsed_time / 1000000.0f;
if (sample_period > 0.1f) {
return;
}
rotations += gyro * sample_period;
}
void MotionInput::UpdateOrientation(u64 elapsed_time) {
if (!IsCalibrated(0.1f)) {
ResetOrientation();
}
// Short name local variable for readability
f32 q1 = quat.w;
f32 q2 = quat.xyz[0];
f32 q3 = quat.xyz[1];
f32 q4 = quat.xyz[2];
const f32 sample_period = elapsed_time / 1000000.0f;
// ignore invalid elapsed time
if (sample_period > 0.1f) {
return;
}
const auto normal_accel = accel.Normalized();
auto rad_gyro = gyro * Common::PI * 2;
const f32 swap = rad_gyro.x;
rad_gyro.x = rad_gyro.y;
rad_gyro.y = -swap;
rad_gyro.z = -rad_gyro.z;
// Ignore drift correction if acceleration is not reliable
if (accel.Length() >= 0.75f && accel.Length() <= 1.25f) {
const f32 ax = -normal_accel.x;
const f32 ay = normal_accel.y;
const f32 az = -normal_accel.z;
// Estimated direction of gravity
const f32 vx = 2.0f * (q2 * q4 - q1 * q3);
const f32 vy = 2.0f * (q1 * q2 + q3 * q4);
const f32 vz = q1 * q1 - q2 * q2 - q3 * q3 + q4 * q4;
// Error is cross product between estimated direction and measured direction of gravity
const Common::Vec3f new_real_error = {az * vx - ax * vz, ay * vz - az * vy,
ax * vy - ay * vx};
derivative_error = new_real_error - real_error;
real_error = new_real_error;
// Prevent integral windup
if (ki != 0.0f && !IsCalibrated(0.05f)) {
integral_error += real_error;
} else {
integral_error = {};
}
// Apply feedback terms
rad_gyro += kp * real_error;
rad_gyro += ki * integral_error;
rad_gyro += kd * derivative_error;
}
const f32 gx = rad_gyro.y;
const f32 gy = rad_gyro.x;
const f32 gz = rad_gyro.z;
// Integrate rate of change of quaternion
const f32 pa = q2;
const f32 pb = q3;
const f32 pc = q4;
q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * sample_period);
q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * sample_period);
q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * sample_period);
q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * sample_period);
quat.w = q1;
quat.xyz[0] = q2;
quat.xyz[1] = q3;
quat.xyz[2] = q4;
quat = quat.Normalized();
}
std::array<Common::Vec3f, 3> MotionInput::GetOrientation() const {
const Common::Quaternion<float> quad{
.xyz = {-quat.xyz[1], -quat.xyz[0], -quat.w},
.w = -quat.xyz[2],
};
const std::array<float, 16> matrix4x4 = quad.ToMatrix();
return {Common::Vec3f(matrix4x4[0], matrix4x4[1], -matrix4x4[2]),
Common::Vec3f(matrix4x4[4], matrix4x4[5], -matrix4x4[6]),
Common::Vec3f(-matrix4x4[8], -matrix4x4[9], matrix4x4[10])};
}
Common::Vec3f MotionInput::GetAcceleration() const {
return accel;
}
Common::Vec3f MotionInput::GetGyroscope() const {
return gyro;
}
Common::Quaternion<f32> MotionInput::GetQuaternion() const {
return quat;
}
Common::Vec3f MotionInput::GetRotations() const {
return rotations;
}
void MotionInput::ResetOrientation() {
if (!reset_enabled) {
return;
}
if (!IsMoving(0.5f) && accel.z <= -0.9f) {
++reset_counter;
if (reset_counter > 900) {
// TODO: calculate quaternion from gravity vector
quat.w = 0;
quat.xyz[0] = 0;
quat.xyz[1] = 0;
quat.xyz[2] = -1;
integral_error = {};
reset_counter = 0;
}
} else {
reset_counter = 0;
}
}
} // namespace InputCommon
|
