diff --git a/vcg/math/gen_normal.h b/vcg/math/gen_normal.h
index 6e94bcb2..3087d09a 100644
--- a/vcg/math/gen_normal.h
+++ b/vcg/math/gen_normal.h
@@ -62,7 +62,7 @@ static Point3x FibonacciPt(int i, int n)
   const ScalarType Phi =  ScalarType(sqrt(5)*0.5 + 0.5);
   const ScalarType phi = 2.0*M_PI* (i/Phi - floor(i/Phi));
   ScalarType cosTheta = 1.0 - (2*i + 1.0)/ScalarType(n);
-    float sinTheta = 1 - cosTheta*cosTheta;
+    ScalarType sinTheta = 1 - cosTheta*cosTheta;
     sinTheta = sqrt(std::min(ScalarType(1),std::max(ScalarType(0),sinTheta)));
     return Point3x(
       cos(phi)*sinTheta,