Files
stm32uav/mculoop/geometry.c

77 lines
1.6 KiB
C

/*
* Copyright 2022 Oleg Borodin <borodin@unix7.org>
*/
#include <stdio.h>
#include <math.h>
#include <geometry.h>
void eulerangle_init(eulerangle_t* a) {
a->z = 0.0;
a->y = 0.0;
a->x = 0.0;
}
void eulerangle_todegress(eulerangle_t* a) {
a->z *= (180.0 / M_PI);
a->y *= (180.0 / M_PI);
a->x *= (180.0 / M_PI);
}
void eulerangle_toradians(eulerangle_t* a) {
a->z *= (M_PI / 180.0);
a->y *= (M_PI / 180.0);
a->x *= (M_PI / 180.0);
}
void eulerangle_norm(eulerangle_t* a) {
double n = sqrt(a->x*a->x + a->y*a->y + a->z*a->z);
a->x *= n;
a->y *= n;
a->z *= n;
}
void quaternion_init(quaternion_t* q) {
q->w = 1.0;
q->x = 0.0;
q->y = 0.0;
q->z = 0.0;
}
void quaternion_toeuler(quaternion_t* q, eulerangle_t* a) {
double x = q->x;
double y = q->y;
double z = q->z;
double w = q->w;
double ax = 0.0;
double ay = 0.0;
double az = 0.0;
double t0 = (x + z)*(x - z); // x^2-z^2
double t1 = (w + y)*(w - y); // w^2-y^2
double n1 = 0.5 * (t0 + t1); // 1/2 x of x'
double n2 = x*y + w*z; // 1/2 y of x'
double n3 = w*y - x*z; // 1/2 z of x'
double t = n1*n1 + n2*n2; // cos(theta)^2
double n4 = 2.0 * (y*z + w*x); // z of y'
az = atan2(n2, n1); // yaw (psi)
ay = atan(n3 / sqrt(t)); // pitch (theta)
if (t != 0.0) { // roll
ax = atan2(n4, t1 - t0);
} else {
ax = (2.0 * atan2(x, w) - copysign(1.0, n3) * az);
}
a->x = ax;
a->y = ay;
a->z = az;
}