diff --git a/stepmania/src/mathlib.c b/stepmania/src/mathlib.c
index 33793f70fc..a8eb597ece 100644
--- a/stepmania/src/mathlib.c
+++ b/stepmania/src/mathlib.c
@@ -62,13 +62,6 @@ i=1;
 	return length;
 }
 
-void VectorInverse (vec3_t v)
-{
-	v[0] = -v[0];
-	v[1] = -v[1];
-	v[2] = -v[2];
-}
-
 void AngleMatrix (const vec3_t angles, float matrix[3][4] )
 {
 	float		angle;
diff --git a/stepmania/src/mathlib.h b/stepmania/src/mathlib.h
index de751586b9..0a7a84ce26 100644
--- a/stepmania/src/mathlib.h
+++ b/stepmania/src/mathlib.h
@@ -37,7 +37,6 @@ int VectorCompare (vec3_t v1, vec3_t v2);
 
 
 vec_t VectorNormalize (vec3_t v);
-void VectorInverse (vec3_t v);
 
 void AngleMatrix (const vec3_t angles, float matrix[3][4] );
 void R_ConcatTransforms (const float in1[3][4], const float in2[3][4], float out[3][4]);