replace hypotenuse calculation in tb_project_to_sphere with a call to hypotf

The function hypotf is available in C99 and has the potential to compute the
same operation more efficiently and with greater precision.

diff --git a/cmd/smyrna/trackball.c b/cmd/smyrna/trackball.c
index d6ef15a6cbdc2fe16ad6ed8bddb239879403bd24..bfba6e5e6cb71de0015f018c225ad89bec9c9a46 100644 (file)
--- a/cmd/smyrna/trackball.c
+++ b/cmd/smyrna/trackball.c
@@ -209,7 +209,7 @@ static float tb_project_to_sphere(float r, float x, float y)
 {
     float d, t, z;
 
-    d = sqrt(x * x + y * y);
+    d = hypotf(x, y);
     if (d < r * 0.70710678118654752440) {      /* Inside sphere */
        z = sqrt(r * r - d * d);
     } else {                   /* On hyperbola */