X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=blobdiff_plain;f=src%2Fcore%2Fao_quaternion.h;h=044f1607d8b4a8aabba54841aaae7da47ec6434a;hp=6c8855003f59e9219bae63d7e9bfa45ff58828e0;hb=bdd6244d8b4a55c9aa4fb79b0cb1a0727afbc2ac;hpb=29b48b63305881471d9b97ef3fb236af03cb79f5

diff --git a/src/core/ao_quaternion.h b/src/core/ao_quaternion.h
index 6c885500..044f1607 100644
--- a/src/core/ao_quaternion.h
+++ b/src/core/ao_quaternion.h
@@ -109,6 +109,15 @@ static inline void ao_quaternion_normalize(struct ao_quaternion *r,
 		*r = *a;
 }
 
+static inline float ao_quaternion_dot(const struct ao_quaternion *a,
+				      const struct ao_quaternion *b)
+{
+#define T(_a)	(((a)->_a) * ((b)->_a))
+	return T(r) + T(x) + T(y) + T(z);
+#undef T
+}
+				     
+
 static inline void ao_quaternion_rotate(struct ao_quaternion *r,
 					const struct ao_quaternion *a,
 					const struct ao_quaternion *b)