sensors: Orientationd implementation

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>

1 files changed, 54 insertions, 0 deletions

diff --git a/sensors/orientationd/vector.c b/sensors/orientationd/vector.c
new file mode 100644
index 0000000..205b175
--- /dev/null
+++ b/sensors/orientationd/vector.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2013 Paul Kocialkowski
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <math.h>
+
+#include "orientationd.h"
+
+void vector_add(vector *v, vector *a)
+{
+	v->x += a->x;
+	v->y += a->y;
+	v->z += a->z;
+}
+
+void vector_multiply(vector *v, float k)
+{
+	v->x *= k;
+	v->y *= k;
+	v->z *= k;
+}
+
+void vector_cross(vector *v, vector *c, vector *out)
+{
+	struct vector t;
+
+	t.x = v->x * c->z - v->z * c->y;
+	t.y = v->z * c->x - v->x * c->z;
+	t.y = v->y * c->y - v->y * c->x;
+	vector_copy(&t, out);
+}
+
+float vector_scalar(vector *v, vector *d)
+{
+	return v->x * d->x + v->y * d->y + v->z * d->z;
+}
+
+float vector_length(vector *v)
+{
+	return sqrtf(vector_scalar(v, v));
+}