Use hexiwear as a GPSIMU-AHRS for Nikon DSLR cameras

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FXOS8700Q
FXAS21000
MBed_Adafruit-GPS-Library
Hexi_OLED_SSD1351

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## sensor_fusion.h@24:cbdf0f7d33bd, 5 months ago (annotated)

- Committer:
- whatnick
- Date:
- Tue Sep 20 04:18:34 2016 +0000
- Revision:
- 24:cbdf0f7d33bd

Added sensor fusion code

### Who changed what in which revision?

User | Revision | Line number | New contents of line |
---|---|---|---|

whatnick | 24:cbdf0f7d33bd | 1 | #ifndef SENSOR_FUSION_H |

whatnick | 24:cbdf0f7d33bd | 2 | #define SENSOR_FUSION_H |

whatnick | 24:cbdf0f7d33bd | 3 | |

whatnick | 24:cbdf0f7d33bd | 4 | #include "mbed.h" |

whatnick | 24:cbdf0f7d33bd | 5 | |

whatnick | 24:cbdf0f7d33bd | 6 | // parameters for 6 DoF sensor fusion calculations |

whatnick | 24:cbdf0f7d33bd | 7 | float PI = 3.14159265358979323846f; |

whatnick | 24:cbdf0f7d33bd | 8 | float GyroMeasError = PI * (60.0f / 180.0f); // gyroscope measurement error in rads/s (start at 60 deg/s), then reduce after ~10 s to 3 |

whatnick | 24:cbdf0f7d33bd | 9 | float beta = sqrt(3.0f / 4.0f) * GyroMeasError; // compute beta |

whatnick | 24:cbdf0f7d33bd | 10 | float GyroMeasDrift = PI * (1.0f / 180.0f); // gyroscope measurement drift in rad/s/s (start at 0.0 deg/s/s) |

whatnick | 24:cbdf0f7d33bd | 11 | float zeta = sqrt(3.0f / 4.0f) * GyroMeasDrift; // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value |

whatnick | 24:cbdf0f7d33bd | 12 | #define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral |

whatnick | 24:cbdf0f7d33bd | 13 | #define Ki 0.0f |

whatnick | 24:cbdf0f7d33bd | 14 | |

whatnick | 24:cbdf0f7d33bd | 15 | |

whatnick | 24:cbdf0f7d33bd | 16 | float q[4] = {1.0f, 0.0f, 0.0f, 0.0f}; // vector to hold quaternion |

whatnick | 24:cbdf0f7d33bd | 17 | float eInt[3] = {0.0f, 0.0f, 0.0f}; // vector to hold integral error for Mahony method |

whatnick | 24:cbdf0f7d33bd | 18 | float pitch, yaw, roll; |

whatnick | 24:cbdf0f7d33bd | 19 | float deltat = 0.0f; // integration interval for both filter schemes |

whatnick | 24:cbdf0f7d33bd | 20 | int lastUpdate = 0, firstUpdate = 0, Now = 0; // used to calculate integration interval |

whatnick | 24:cbdf0f7d33bd | 21 | |

whatnick | 24:cbdf0f7d33bd | 22 | // Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays" |

whatnick | 24:cbdf0f7d33bd | 23 | // (see http://www.x-io.co.uk/category/open-source/ for examples and more details) |

whatnick | 24:cbdf0f7d33bd | 24 | // which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute |

whatnick | 24:cbdf0f7d33bd | 25 | // device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc. |

whatnick | 24:cbdf0f7d33bd | 26 | // The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms |

whatnick | 24:cbdf0f7d33bd | 27 | // but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz! |

whatnick | 24:cbdf0f7d33bd | 28 | void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) |

whatnick | 24:cbdf0f7d33bd | 29 | { |

whatnick | 24:cbdf0f7d33bd | 30 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |

whatnick | 24:cbdf0f7d33bd | 31 | float norm; |

whatnick | 24:cbdf0f7d33bd | 32 | float hx, hy, _2bx, _2bz; |

whatnick | 24:cbdf0f7d33bd | 33 | float s1, s2, s3, s4; |

whatnick | 24:cbdf0f7d33bd | 34 | float qDot1, qDot2, qDot3, qDot4; |

whatnick | 24:cbdf0f7d33bd | 35 | |

whatnick | 24:cbdf0f7d33bd | 36 | // Auxiliary variables to avoid repeated arithmetic |

whatnick | 24:cbdf0f7d33bd | 37 | float _2q1mx; |

whatnick | 24:cbdf0f7d33bd | 38 | float _2q1my; |

whatnick | 24:cbdf0f7d33bd | 39 | float _2q1mz; |

whatnick | 24:cbdf0f7d33bd | 40 | float _2q2mx; |

whatnick | 24:cbdf0f7d33bd | 41 | float _4bx; |

whatnick | 24:cbdf0f7d33bd | 42 | float _4bz; |

whatnick | 24:cbdf0f7d33bd | 43 | float _2q1 = 2.0f * q1; |

whatnick | 24:cbdf0f7d33bd | 44 | float _2q2 = 2.0f * q2; |

whatnick | 24:cbdf0f7d33bd | 45 | float _2q3 = 2.0f * q3; |

whatnick | 24:cbdf0f7d33bd | 46 | float _2q4 = 2.0f * q4; |

whatnick | 24:cbdf0f7d33bd | 47 | float _2q1q3 = 2.0f * q1 * q3; |

whatnick | 24:cbdf0f7d33bd | 48 | float _2q3q4 = 2.0f * q3 * q4; |

whatnick | 24:cbdf0f7d33bd | 49 | float q1q1 = q1 * q1; |

whatnick | 24:cbdf0f7d33bd | 50 | float q1q2 = q1 * q2; |

whatnick | 24:cbdf0f7d33bd | 51 | float q1q3 = q1 * q3; |

whatnick | 24:cbdf0f7d33bd | 52 | float q1q4 = q1 * q4; |

whatnick | 24:cbdf0f7d33bd | 53 | float q2q2 = q2 * q2; |

whatnick | 24:cbdf0f7d33bd | 54 | float q2q3 = q2 * q3; |

whatnick | 24:cbdf0f7d33bd | 55 | float q2q4 = q2 * q4; |

whatnick | 24:cbdf0f7d33bd | 56 | float q3q3 = q3 * q3; |

whatnick | 24:cbdf0f7d33bd | 57 | float q3q4 = q3 * q4; |

whatnick | 24:cbdf0f7d33bd | 58 | float q4q4 = q4 * q4; |

whatnick | 24:cbdf0f7d33bd | 59 | |

whatnick | 24:cbdf0f7d33bd | 60 | // Normalise accelerometer measurement |

whatnick | 24:cbdf0f7d33bd | 61 | norm = sqrt(ax * ax + ay * ay + az * az); |

whatnick | 24:cbdf0f7d33bd | 62 | if (norm == 0.0f) return; // handle NaN |

whatnick | 24:cbdf0f7d33bd | 63 | norm = 1.0f/norm; |

whatnick | 24:cbdf0f7d33bd | 64 | ax *= norm; |

whatnick | 24:cbdf0f7d33bd | 65 | ay *= norm; |

whatnick | 24:cbdf0f7d33bd | 66 | az *= norm; |

whatnick | 24:cbdf0f7d33bd | 67 | |

whatnick | 24:cbdf0f7d33bd | 68 | // Normalise magnetometer measurement |

whatnick | 24:cbdf0f7d33bd | 69 | norm = sqrt(mx * mx + my * my + mz * mz); |

whatnick | 24:cbdf0f7d33bd | 70 | if (norm == 0.0f) return; // handle NaN |

whatnick | 24:cbdf0f7d33bd | 71 | norm = 1.0f/norm; |

whatnick | 24:cbdf0f7d33bd | 72 | mx *= norm; |

whatnick | 24:cbdf0f7d33bd | 73 | my *= norm; |

whatnick | 24:cbdf0f7d33bd | 74 | mz *= norm; |

whatnick | 24:cbdf0f7d33bd | 75 | |

whatnick | 24:cbdf0f7d33bd | 76 | // Reference direction of Earth's magnetic field |

whatnick | 24:cbdf0f7d33bd | 77 | _2q1mx = 2.0f * q1 * mx; |

whatnick | 24:cbdf0f7d33bd | 78 | _2q1my = 2.0f * q1 * my; |

whatnick | 24:cbdf0f7d33bd | 79 | _2q1mz = 2.0f * q1 * mz; |

whatnick | 24:cbdf0f7d33bd | 80 | _2q2mx = 2.0f * q2 * mx; |

whatnick | 24:cbdf0f7d33bd | 81 | hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4; |

whatnick | 24:cbdf0f7d33bd | 82 | hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4; |

whatnick | 24:cbdf0f7d33bd | 83 | _2bx = sqrt(hx * hx + hy * hy); |

whatnick | 24:cbdf0f7d33bd | 84 | _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4; |

whatnick | 24:cbdf0f7d33bd | 85 | _4bx = 2.0f * _2bx; |

whatnick | 24:cbdf0f7d33bd | 86 | _4bz = 2.0f * _2bz; |

whatnick | 24:cbdf0f7d33bd | 87 | |

whatnick | 24:cbdf0f7d33bd | 88 | // Gradient decent algorithm corrective step |

whatnick | 24:cbdf0f7d33bd | 89 | s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |

whatnick | 24:cbdf0f7d33bd | 90 | s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |

whatnick | 24:cbdf0f7d33bd | 91 | s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |

whatnick | 24:cbdf0f7d33bd | 92 | s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz); |

whatnick | 24:cbdf0f7d33bd | 93 | norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4); // normalise step magnitude |

whatnick | 24:cbdf0f7d33bd | 94 | norm = 1.0f/norm; |

whatnick | 24:cbdf0f7d33bd | 95 | s1 *= norm; |

whatnick | 24:cbdf0f7d33bd | 96 | s2 *= norm; |

whatnick | 24:cbdf0f7d33bd | 97 | s3 *= norm; |

whatnick | 24:cbdf0f7d33bd | 98 | s4 *= norm; |

whatnick | 24:cbdf0f7d33bd | 99 | |

whatnick | 24:cbdf0f7d33bd | 100 | // Compute rate of change of quaternion |

whatnick | 24:cbdf0f7d33bd | 101 | qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1; |

whatnick | 24:cbdf0f7d33bd | 102 | qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2; |

whatnick | 24:cbdf0f7d33bd | 103 | qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3; |

whatnick | 24:cbdf0f7d33bd | 104 | qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4; |

whatnick | 24:cbdf0f7d33bd | 105 | |

whatnick | 24:cbdf0f7d33bd | 106 | // Integrate to yield quaternion |

whatnick | 24:cbdf0f7d33bd | 107 | q1 += qDot1 * deltat; |

whatnick | 24:cbdf0f7d33bd | 108 | q2 += qDot2 * deltat; |

whatnick | 24:cbdf0f7d33bd | 109 | q3 += qDot3 * deltat; |

whatnick | 24:cbdf0f7d33bd | 110 | q4 += qDot4 * deltat; |

whatnick | 24:cbdf0f7d33bd | 111 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); // normalise quaternion |

whatnick | 24:cbdf0f7d33bd | 112 | norm = 1.0f/norm; |

whatnick | 24:cbdf0f7d33bd | 113 | q[0] = q1 * norm; |

whatnick | 24:cbdf0f7d33bd | 114 | q[1] = q2 * norm; |

whatnick | 24:cbdf0f7d33bd | 115 | q[2] = q3 * norm; |

whatnick | 24:cbdf0f7d33bd | 116 | q[3] = q4 * norm; |

whatnick | 24:cbdf0f7d33bd | 117 | |

whatnick | 24:cbdf0f7d33bd | 118 | } |

whatnick | 24:cbdf0f7d33bd | 119 | |

whatnick | 24:cbdf0f7d33bd | 120 | // Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and |

whatnick | 24:cbdf0f7d33bd | 121 | // measured ones. |

whatnick | 24:cbdf0f7d33bd | 122 | void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz) |

whatnick | 24:cbdf0f7d33bd | 123 | { |

whatnick | 24:cbdf0f7d33bd | 124 | float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3]; // short name local variable for readability |

whatnick | 24:cbdf0f7d33bd | 125 | float norm; |

whatnick | 24:cbdf0f7d33bd | 126 | float hx, hy, bx, bz; |

whatnick | 24:cbdf0f7d33bd | 127 | float vx, vy, vz, wx, wy, wz; |

whatnick | 24:cbdf0f7d33bd | 128 | float ex, ey, ez; |

whatnick | 24:cbdf0f7d33bd | 129 | float pa, pb, pc; |

whatnick | 24:cbdf0f7d33bd | 130 | |

whatnick | 24:cbdf0f7d33bd | 131 | // Auxiliary variables to avoid repeated arithmetic |

whatnick | 24:cbdf0f7d33bd | 132 | float q1q1 = q1 * q1; |

whatnick | 24:cbdf0f7d33bd | 133 | float q1q2 = q1 * q2; |

whatnick | 24:cbdf0f7d33bd | 134 | float q1q3 = q1 * q3; |

whatnick | 24:cbdf0f7d33bd | 135 | float q1q4 = q1 * q4; |

whatnick | 24:cbdf0f7d33bd | 136 | float q2q2 = q2 * q2; |

whatnick | 24:cbdf0f7d33bd | 137 | float q2q3 = q2 * q3; |

whatnick | 24:cbdf0f7d33bd | 138 | float q2q4 = q2 * q4; |

whatnick | 24:cbdf0f7d33bd | 139 | float q3q3 = q3 * q3; |

whatnick | 24:cbdf0f7d33bd | 140 | float q3q4 = q3 * q4; |

whatnick | 24:cbdf0f7d33bd | 141 | float q4q4 = q4 * q4; |

whatnick | 24:cbdf0f7d33bd | 142 | |

whatnick | 24:cbdf0f7d33bd | 143 | // Normalise accelerometer measurement |

whatnick | 24:cbdf0f7d33bd | 144 | norm = sqrt(ax * ax + ay * ay + az * az); |

whatnick | 24:cbdf0f7d33bd | 145 | if (norm == 0.0f) return; // handle NaN |

whatnick | 24:cbdf0f7d33bd | 146 | norm = 1.0f / norm; // use reciprocal for division |

whatnick | 24:cbdf0f7d33bd | 147 | ax *= norm; |

whatnick | 24:cbdf0f7d33bd | 148 | ay *= norm; |

whatnick | 24:cbdf0f7d33bd | 149 | az *= norm; |

whatnick | 24:cbdf0f7d33bd | 150 | |

whatnick | 24:cbdf0f7d33bd | 151 | // Normalise magnetometer measurement |

whatnick | 24:cbdf0f7d33bd | 152 | norm = sqrt(mx * mx + my * my + mz * mz); |

whatnick | 24:cbdf0f7d33bd | 153 | if (norm == 0.0f) return; // handle NaN |

whatnick | 24:cbdf0f7d33bd | 154 | norm = 1.0f / norm; // use reciprocal for division |

whatnick | 24:cbdf0f7d33bd | 155 | mx *= norm; |

whatnick | 24:cbdf0f7d33bd | 156 | my *= norm; |

whatnick | 24:cbdf0f7d33bd | 157 | mz *= norm; |

whatnick | 24:cbdf0f7d33bd | 158 | |

whatnick | 24:cbdf0f7d33bd | 159 | // Reference direction of Earth's magnetic field |

whatnick | 24:cbdf0f7d33bd | 160 | hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3); |

whatnick | 24:cbdf0f7d33bd | 161 | hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2); |

whatnick | 24:cbdf0f7d33bd | 162 | bx = sqrt((hx * hx) + (hy * hy)); |

whatnick | 24:cbdf0f7d33bd | 163 | bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3); |

whatnick | 24:cbdf0f7d33bd | 164 | |

whatnick | 24:cbdf0f7d33bd | 165 | // Estimated direction of gravity and magnetic field |

whatnick | 24:cbdf0f7d33bd | 166 | vx = 2.0f * (q2q4 - q1q3); |

whatnick | 24:cbdf0f7d33bd | 167 | vy = 2.0f * (q1q2 + q3q4); |

whatnick | 24:cbdf0f7d33bd | 168 | vz = q1q1 - q2q2 - q3q3 + q4q4; |

whatnick | 24:cbdf0f7d33bd | 169 | wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3); |

whatnick | 24:cbdf0f7d33bd | 170 | wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4); |

whatnick | 24:cbdf0f7d33bd | 171 | wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3); |

whatnick | 24:cbdf0f7d33bd | 172 | |

whatnick | 24:cbdf0f7d33bd | 173 | // Error is cross product between estimated direction and measured direction of gravity |

whatnick | 24:cbdf0f7d33bd | 174 | ex = (ay * vz - az * vy) + (my * wz - mz * wy); |

whatnick | 24:cbdf0f7d33bd | 175 | ey = (az * vx - ax * vz) + (mz * wx - mx * wz); |

whatnick | 24:cbdf0f7d33bd | 176 | ez = (ax * vy - ay * vx) + (mx * wy - my * wx); |

whatnick | 24:cbdf0f7d33bd | 177 | if (Ki > 0.0f) { |

whatnick | 24:cbdf0f7d33bd | 178 | eInt[0] += ex; // accumulate integral error |

whatnick | 24:cbdf0f7d33bd | 179 | eInt[1] += ey; |

whatnick | 24:cbdf0f7d33bd | 180 | eInt[2] += ez; |

whatnick | 24:cbdf0f7d33bd | 181 | } else { |

whatnick | 24:cbdf0f7d33bd | 182 | eInt[0] = 0.0f; // prevent integral wind up |

whatnick | 24:cbdf0f7d33bd | 183 | eInt[1] = 0.0f; |

whatnick | 24:cbdf0f7d33bd | 184 | eInt[2] = 0.0f; |

whatnick | 24:cbdf0f7d33bd | 185 | } |

whatnick | 24:cbdf0f7d33bd | 186 | |

whatnick | 24:cbdf0f7d33bd | 187 | // Apply feedback terms |

whatnick | 24:cbdf0f7d33bd | 188 | gx = gx + Kp * ex + Ki * eInt[0]; |

whatnick | 24:cbdf0f7d33bd | 189 | gy = gy + Kp * ey + Ki * eInt[1]; |

whatnick | 24:cbdf0f7d33bd | 190 | gz = gz + Kp * ez + Ki * eInt[2]; |

whatnick | 24:cbdf0f7d33bd | 191 | |

whatnick | 24:cbdf0f7d33bd | 192 | // Integrate rate of change of quaternion |

whatnick | 24:cbdf0f7d33bd | 193 | pa = q2; |

whatnick | 24:cbdf0f7d33bd | 194 | pb = q3; |

whatnick | 24:cbdf0f7d33bd | 195 | pc = q4; |

whatnick | 24:cbdf0f7d33bd | 196 | q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat); |

whatnick | 24:cbdf0f7d33bd | 197 | q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat); |

whatnick | 24:cbdf0f7d33bd | 198 | q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat); |

whatnick | 24:cbdf0f7d33bd | 199 | q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat); |

whatnick | 24:cbdf0f7d33bd | 200 | |

whatnick | 24:cbdf0f7d33bd | 201 | // Normalise quaternion |

whatnick | 24:cbdf0f7d33bd | 202 | norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4); |

whatnick | 24:cbdf0f7d33bd | 203 | norm = 1.0f / norm; |

whatnick | 24:cbdf0f7d33bd | 204 | q[0] = q1 * norm; |

whatnick | 24:cbdf0f7d33bd | 205 | q[1] = q2 * norm; |

whatnick | 24:cbdf0f7d33bd | 206 | q[2] = q3 * norm; |

whatnick | 24:cbdf0f7d33bd | 207 | q[3] = q4 * norm; |

whatnick | 24:cbdf0f7d33bd | 208 | |

whatnick | 24:cbdf0f7d33bd | 209 | } |

whatnick | 24:cbdf0f7d33bd | 210 | |

whatnick | 24:cbdf0f7d33bd | 211 | #endif |