altos: Add gyro-based orientation tracking

[fw/altos] / src / test / ao_quaternion_test.c

diff --git a/src/test/ao_quaternion_test.c b/src/test/ao_quaternion_test.c
new file mode 100644 (file)
index 0000000..0e4b5b0
--- /dev/null
+++ b/src/test/ao_quaternion_test.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2013 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <getopt.h>
+#include <math.h>
+
+#include "ao_quaternion.h"
+
+static void
+print_q(char *name, struct ao_quaternion *q)
+{
+       printf ("%8.8s: r%8.5f x%8.5f y%8.5f z%8.5f ", name,
+               q->r, q->x, q->y, q->z);
+}
+
+int main(int argc, char **argv)
+{
+       struct ao_quaternion    position;
+       struct ao_quaternion    rotation;
+       struct ao_quaternion    little_rotation;
+       int                     i;
+
+       /* unit x vector */
+       ao_quaternion_init_vector(&position, 1, 0, 0);
+
+       /* zero rotation */
+       ao_quaternion_init_zero_rotation(&rotation);
+
+       /* π/16 rotation around Z axis */
+       ao_quaternion_init_rotation(&little_rotation, 0, 0, 1,
+                                   sin((M_PI/16)/2),
+                                   cos((M_PI/16)/2));
+       for (i = 0; i <= 16; i++) {
+               struct ao_quaternion    rotated;
+
+               ao_quaternion_rotate(&rotated, &position, &rotation);
+               print_q("position", &position);
+               print_q("rotated", &rotated);
+               print_q("rotation", &rotation);
+               printf ("\n");
+               ao_quaternion_multiply(&rotation, &rotation, &little_rotation);
+               ao_quaternion_normalize(&rotation, &rotation);
+       }
+       return 0;
+}
+